Mailing-List: contact crunch-commits-help@incubator.apache.org; run by ezmlm
Precedence: bulk
Reply-To: crunch-dev@incubator.apache.org
Content-Type: text/plain; charset="us-ascii"
MIME-Version: 1.0
Content-Transfer-Encoding: 7bit
From: jwills@apache.org
To: crunch-commits@incubator.apache.org
Subject: [10/33] CRUNCH-8: Moving the code into multiple Maven modules.
 Contributed by Matthias Friedrich
Message-Id: <20120711051446.2BD0CDAE0@tyr.zones.apache.org>
Date: Wed, 11 Jul 2012 05:14:46 +0000 (UTC)

http://git-wip-us.apache.org/repos/asf/incubator-crunch/blob/83acb813/crunch/src/main/java/org/apache/crunch/types/writable/Writables.java
----------------------------------------------------------------------
diff --git a/crunch/src/main/java/org/apache/crunch/types/writable/Writables.java b/crunch/src/main/java/org/apache/crunch/types/writable/Writables.java
new file mode 100644
index 0000000..08b6c64
--- /dev/null
+++ b/crunch/src/main/java/org/apache/crunch/types/writable/Writables.java
@@ -0,0 +1,634 @@
+/**
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.crunch.types.writable;
+
+import java.io.ByteArrayInputStream;
+import java.io.ByteArrayOutputStream;
+import java.io.DataInput;
+import java.io.DataInputStream;
+import java.io.DataOutputStream;
+import java.nio.ByteBuffer;
+import java.util.Collection;
+import java.util.List;
+import java.util.Map;
+
+import org.apache.hadoop.conf.Configuration;
+import org.apache.hadoop.io.BooleanWritable;
+import org.apache.hadoop.io.BytesWritable;
+import org.apache.hadoop.io.DoubleWritable;
+import org.apache.hadoop.io.FloatWritable;
+import org.apache.hadoop.io.IntWritable;
+import org.apache.hadoop.io.LongWritable;
+import org.apache.hadoop.io.MapWritable;
+import org.apache.hadoop.io.NullWritable;
+import org.apache.hadoop.io.Text;
+import org.apache.hadoop.io.Writable;
+
+import org.apache.crunch.MapFn;
+import org.apache.crunch.Pair;
+import org.apache.crunch.Tuple;
+import org.apache.crunch.Tuple3;
+import org.apache.crunch.Tuple4;
+import org.apache.crunch.TupleN;
+import org.apache.crunch.fn.CompositeMapFn;
+import org.apache.crunch.fn.IdentityFn;
+import org.apache.crunch.impl.mr.run.CrunchRuntimeException;
+import org.apache.crunch.types.PType;
+import org.apache.crunch.types.TupleFactory;
+import org.apache.crunch.util.PTypes;
+import com.google.common.collect.ImmutableMap;
+import com.google.common.collect.Lists;
+import com.google.common.collect.Maps;
+
+/**
+ * Defines static methods that are analogous to the methods defined in
+ * {@link WritableTypeFamily} for convenient static importing.
+ * 
+ */
+public class Writables {
+  private static final MapFn<NullWritable, Void> NULL_WRITABLE_TO_VOID = new MapFn<NullWritable, Void>() {
+    @Override
+    public Void map(NullWritable input) {
+      return null;
+    }
+  };
+
+  private static final MapFn<Void, NullWritable> VOID_TO_NULL_WRITABLE = new MapFn<Void, NullWritable>() {
+    @Override
+    public NullWritable map(Void input) {
+      return NullWritable.get();
+    }
+  };
+  
+  private static final MapFn<Text, String> TEXT_TO_STRING = new MapFn<Text, String>() {
+    @Override
+    public String map(Text input) {
+      return input.toString();
+    }
+  };
+
+  private static final MapFn<String, Text> STRING_TO_TEXT = new MapFn<String, Text>() {
+    @Override
+    public Text map(String input) {
+      return new Text(input);
+    }
+  };
+
+  private static final MapFn<IntWritable, Integer> IW_TO_INT = new MapFn<IntWritable, Integer>() {
+    @Override
+    public Integer map(IntWritable input) {
+      return input.get();
+    }
+  };
+
+  private static final MapFn<Integer, IntWritable> INT_TO_IW = new MapFn<Integer, IntWritable>() {
+    @Override
+    public IntWritable map(Integer input) {
+      return new IntWritable(input);
+    }
+  };
+
+  private static final MapFn<LongWritable, Long> LW_TO_LONG = new MapFn<LongWritable, Long>() {
+    @Override
+    public Long map(LongWritable input) {
+      return input.get();
+    }
+  };
+
+  private static final MapFn<Long, LongWritable> LONG_TO_LW = new MapFn<Long, LongWritable>() {
+    @Override
+    public LongWritable map(Long input) {
+      return new LongWritable(input);
+    }
+  };
+
+  private static final MapFn<FloatWritable, Float> FW_TO_FLOAT = new MapFn<FloatWritable, Float>() {
+    @Override
+    public Float map(FloatWritable input) {
+      return input.get();
+    }
+  };
+
+  private static final MapFn<Float, FloatWritable> FLOAT_TO_FW = new MapFn<Float, FloatWritable>() {
+    @Override
+    public FloatWritable map(Float input) {
+      return new FloatWritable(input);
+    }
+  };
+
+  private static final MapFn<DoubleWritable, Double> DW_TO_DOUBLE = new MapFn<DoubleWritable, Double>() {
+    @Override
+    public Double map(DoubleWritable input) {
+      return input.get();
+    }
+  };
+
+  private static final MapFn<Double, DoubleWritable> DOUBLE_TO_DW = new MapFn<Double, DoubleWritable>() {
+    @Override
+    public DoubleWritable map(Double input) {
+      return new DoubleWritable(input);
+    }
+  };
+
+  private static final MapFn<BooleanWritable, Boolean> BW_TO_BOOLEAN = new MapFn<BooleanWritable, Boolean>() {
+    @Override
+    public Boolean map(BooleanWritable input) {
+      return input.get();
+    }
+  };
+
+  private static final BooleanWritable TRUE = new BooleanWritable(true);
+  private static final BooleanWritable FALSE = new BooleanWritable(false);
+  private static final MapFn<Boolean, BooleanWritable> BOOLEAN_TO_BW = new MapFn<Boolean, BooleanWritable>() {
+    @Override
+    public BooleanWritable map(Boolean input) {
+      return input == Boolean.TRUE ? TRUE : FALSE;
+    }
+  };
+  
+  private static final MapFn<BytesWritable, ByteBuffer> BW_TO_BB = new MapFn<BytesWritable, ByteBuffer>() {
+    @Override
+    public ByteBuffer map(BytesWritable input) {
+      return ByteBuffer.wrap(input.getBytes(), 0, input.getLength());
+    }
+  };
+  
+  private static final MapFn<ByteBuffer, BytesWritable> BB_TO_BW = new MapFn<ByteBuffer, BytesWritable>() {
+    @Override
+    public BytesWritable map(ByteBuffer input) {
+      BytesWritable bw = new BytesWritable();
+      bw.set(input.array(), input.arrayOffset(), input.limit());
+      return bw;
+    }
+  };
+
+  private static <S, W extends Writable> WritableType<S, W> create(Class<S> typeClass,
+      Class<W> writableClass, MapFn<W, S> inputDoFn, MapFn<S, W> outputDoFn) {
+    return new WritableType<S, W>(typeClass, writableClass, inputDoFn,
+        outputDoFn);
+  }
+
+  private static final WritableType<Void, NullWritable> nulls = create(Void.class, NullWritable.class,
+      NULL_WRITABLE_TO_VOID, VOID_TO_NULL_WRITABLE);
+  private static final WritableType<String, Text> strings = create(String.class, Text.class,
+      TEXT_TO_STRING, STRING_TO_TEXT);
+  private static final WritableType<Long, LongWritable> longs = create(Long.class, LongWritable.class,
+      LW_TO_LONG, LONG_TO_LW);
+  private static final WritableType<Integer, IntWritable> ints = create(Integer.class, IntWritable.class,
+      IW_TO_INT, INT_TO_IW);
+  private static final WritableType<Float, FloatWritable> floats = create(Float.class, FloatWritable.class,
+      FW_TO_FLOAT, FLOAT_TO_FW);
+  private static final WritableType<Double, DoubleWritable> doubles = create(Double.class,
+      DoubleWritable.class, DW_TO_DOUBLE, DOUBLE_TO_DW);
+  private static final WritableType<Boolean, BooleanWritable> booleans = create(Boolean.class,
+      BooleanWritable.class, BW_TO_BOOLEAN, BOOLEAN_TO_BW);
+  private static final WritableType<ByteBuffer, BytesWritable> bytes = create(ByteBuffer.class,
+      BytesWritable.class, BW_TO_BB, BB_TO_BW);
+
+  private static final Map<Class<?>, PType<?>> PRIMITIVES = ImmutableMap.<Class<?>, PType<?>>builder()
+      .put(String.class, strings)
+      .put(Long.class, longs)
+      .put(Integer.class, ints)
+      .put(Float.class, floats)
+      .put(Double.class, doubles)
+      .put(Boolean.class, booleans)
+      .put(ByteBuffer.class, bytes)
+      .build();
+  
+  private static final Map<Class<?>, WritableType<?, ?>> EXTENSIONS = Maps.newHashMap();
+  
+  public static <T> PType<T> getPrimitiveType(Class<T> clazz) {
+    return (PType<T>) PRIMITIVES.get(clazz);
+  }
+  
+  public static <T> void register(Class<T> clazz, WritableType<T, ? extends Writable> ptype) {
+    EXTENSIONS.put(clazz, ptype);
+  }
+  
+  public static final WritableType<Void, NullWritable> nulls() {
+    return nulls;
+  }
+
+  public static final WritableType<String, Text> strings() {
+    return strings;
+  }
+
+  public static final WritableType<Long, LongWritable> longs() {
+    return longs;
+  }
+
+  public static final WritableType<Integer, IntWritable> ints() {
+    return ints;
+  }
+
+  public static final WritableType<Float, FloatWritable> floats() {
+    return floats;
+  }
+
+  public static final WritableType<Double, DoubleWritable> doubles() {
+    return doubles;
+  }
+
+  public static final WritableType<Boolean, BooleanWritable> booleans() {
+    return booleans;
+  }
+  
+  public static final WritableType<ByteBuffer, BytesWritable> bytes() {
+    return bytes;
+  }
+  
+  public static final <T, W extends Writable> WritableType<T, W> records(Class<T> clazz) {
+    if (EXTENSIONS.containsKey(clazz)) {
+      return (WritableType<T, W>) EXTENSIONS.get(clazz);
+    }
+    return (WritableType<T, W>) writables(clazz.asSubclass(Writable.class));
+  }
+
+  public static <W extends Writable> WritableType<W, W> writables(Class<W> clazz) {
+    MapFn wIdentity = IdentityFn.getInstance();
+    return new WritableType<W, W>(clazz, clazz, wIdentity, wIdentity);
+  }
+
+  public static <K, V> WritableTableType<K, V> tableOf(
+      PType<K> key, PType<V> value) {
+    if (key instanceof WritableTableType) {
+      WritableTableType wtt = (WritableTableType) key;
+      key = pairs(wtt.getKeyType(), wtt.getValueType());
+    } else if (!(key instanceof WritableType)) {
+      throw new IllegalArgumentException("Key type must be of class WritableType");
+    }
+    if (value instanceof WritableTableType) {
+      WritableTableType wtt = (WritableTableType) value;
+      value = pairs(wtt.getKeyType(), wtt.getValueType());
+    } else if (!(value instanceof WritableType)) {
+      throw new IllegalArgumentException("Value type must be of class WritableType");
+    }
+    return new WritableTableType((WritableType) key, (WritableType) value);
+  }
+
+  /**
+   * For mapping from {@link TupleWritable} instances to {@link Tuple}s.
+   * 
+   */
+  private static class TWTupleMapFn extends MapFn<TupleWritable, Tuple> {
+    private final TupleFactory<?> tupleFactory;
+    private final List<MapFn> fns;
+
+    private transient Object[] values;
+
+    public TWTupleMapFn(TupleFactory<?> tupleFactory, PType<?>... ptypes) {
+      this.tupleFactory = tupleFactory;
+      this.fns = Lists.newArrayList();
+      for (PType ptype : ptypes) {
+        fns.add(ptype.getInputMapFn());
+      }
+    }
+
+    @Override
+    public void configure(Configuration conf) {
+      for (MapFn fn : fns) {
+        fn.configure(conf);
+      }
+    }
+
+    @Override
+    public void setConfigurationForTest(Configuration conf) {
+      for (MapFn fn : fns) {
+        fn.setConfigurationForTest(conf);
+      }
+    }
+    
+    @Override
+    public void initialize() {
+      for (MapFn fn : fns) {
+        fn.setContext(getContext());
+      }
+      // The rest of the methods allocate new
+      // objects each time. However this one
+      // uses Tuple.tuplify which does a copy
+      this.values = new Object[fns.size()];
+      tupleFactory.initialize();
+    }
+
+    @Override
+    public Tuple map(TupleWritable in) {
+      for (int i = 0; i < values.length; i++) {
+        if (in.has(i)) {
+          values[i] = fns.get(i).map(in.get(i));
+        } else {
+          values[i] = null;
+        }
+      }
+      return tupleFactory.makeTuple(values);
+    }
+  }
+
+  /**
+   * For mapping from {@code Tuple}s to {@code TupleWritable}s.
+   * 
+   */
+  private static class TupleTWMapFn extends MapFn<Tuple, TupleWritable> {
+    
+    private transient TupleWritable writable;
+    private transient Writable[] values;
+
+    private final List<MapFn> fns;
+
+    public TupleTWMapFn(PType<?>... ptypes) {
+      this.fns = Lists.newArrayList();
+      for (PType<?> ptype : ptypes) {
+        fns.add(ptype.getOutputMapFn());
+      }
+    }
+
+    @Override
+    public void configure(Configuration conf) {
+      for (MapFn fn : fns) {
+        fn.configure(conf);
+      }
+    }
+
+    @Override
+    public void setConfigurationForTest(Configuration conf) {
+      for (MapFn fn : fns) {
+        fn.setConfigurationForTest(conf);
+      }
+    }
+
+    @Override
+    public void initialize() {
+      this.values = new Writable[fns.size()];
+      this.writable = new TupleWritable(values);
+      for (MapFn fn : fns) {
+        fn.setContext(getContext());
+      }
+    }
+
+    @Override
+    public TupleWritable map(Tuple input) {
+      writable.clearWritten();
+      for (int i = 0; i < input.size(); i++) {
+        Object value = input.get(i);
+        if (value != null) {
+          writable.setWritten(i);
+          values[i] = (Writable) fns.get(i).map(value);
+        }
+      }
+      return writable;
+    }
+  }
+
+  public static <V1, V2> WritableType<Pair<V1, V2>, TupleWritable> pairs(PType<V1> p1, PType<V2> p2) {
+    TWTupleMapFn input = new TWTupleMapFn(TupleFactory.PAIR, p1, p2);
+    TupleTWMapFn output = new TupleTWMapFn(p1, p2);
+    return new WritableType(Pair.class, TupleWritable.class, input, output, p1, p2);
+  }
+
+  public static <V1, V2, V3> WritableType<Tuple3<V1, V2, V3>, TupleWritable> triples(PType<V1> p1,
+      PType<V2> p2, PType<V3> p3) {
+    TWTupleMapFn input = new TWTupleMapFn(TupleFactory.TUPLE3, p1, p2, p3);
+    TupleTWMapFn output = new TupleTWMapFn(p1, p2, p3);
+    return new WritableType(Tuple3.class, TupleWritable.class,
+        input,
+        output,
+        p1, p2, p3);
+  }
+
+  public static <V1, V2, V3, V4> WritableType<Tuple4<V1, V2, V3, V4>, TupleWritable> quads(PType<V1> p1,
+      PType<V2> p2, PType<V3> p3, PType<V4> p4) {
+    TWTupleMapFn input = new TWTupleMapFn(TupleFactory.TUPLE4, p1, p2, p3, p4);
+    TupleTWMapFn output = new TupleTWMapFn(p1, p2, p3, p4);
+    return new WritableType(Tuple4.class, TupleWritable.class,
+        input,
+        output,
+        p1, p2, p3, p4);
+  }
+
+  public static WritableType<TupleN, TupleWritable> tuples(PType... ptypes) {
+    TWTupleMapFn input = new TWTupleMapFn(TupleFactory.TUPLEN, ptypes);
+    TupleTWMapFn output = new TupleTWMapFn(ptypes);
+    return new WritableType(TupleN.class, TupleWritable.class, input, output, ptypes);
+  }
+
+  public static <T extends Tuple> PType<T> tuples(Class<T> clazz, PType... ptypes) {
+    Class[] typeArgs = new Class[ptypes.length];
+    for (int i = 0; i < typeArgs.length; i++) {
+      typeArgs[i] = ptypes[i].getTypeClass();
+    }
+    TupleFactory<T> factory = TupleFactory.create(clazz, typeArgs);
+    TWTupleMapFn input = new TWTupleMapFn(factory, ptypes);
+    TupleTWMapFn output = new TupleTWMapFn(ptypes);
+    return new WritableType(clazz, TupleWritable.class, input, output, ptypes);  
+  }
+  
+  public static <S, T> PType<T> derived(Class<T> clazz, MapFn<S, T> inputFn, MapFn<T, S> outputFn,
+      PType<S> base) {
+    WritableType<S, ?> wt = (WritableType<S, ?>) base;
+    MapFn input = new CompositeMapFn(wt.getInputMapFn(), inputFn);
+    MapFn output = new CompositeMapFn(outputFn, wt.getOutputMapFn());
+    return new WritableType(clazz, wt.getSerializationClass(), input, output, base.getSubTypes().toArray(new PType[0]));
+  }
+  
+  private static class ArrayCollectionMapFn<T> extends
+      MapFn<GenericArrayWritable, Collection<T>> {
+    private final MapFn<Object, T> mapFn;
+
+    public ArrayCollectionMapFn(MapFn<Object, T> mapFn) {
+      this.mapFn = mapFn;
+    }
+
+    @Override
+    public void configure(Configuration conf) {
+      mapFn.configure(conf);
+    }
+
+    @Override
+    public void setConfigurationForTest(Configuration conf) {
+      mapFn.setConfigurationForTest(conf);
+    }
+    
+    @Override
+    public void initialize() {
+      mapFn.setContext(getContext());   
+    }
+    
+    @Override
+    public Collection<T> map(GenericArrayWritable input) {
+      Collection<T> collection = Lists.newArrayList();
+      for (Writable writable : input.get()) {
+        collection.add(mapFn.map(writable));
+      }
+      return collection;
+    }
+  }
+
+  private static class CollectionArrayMapFn<T> extends
+      MapFn<Collection<T>, GenericArrayWritable> {
+    
+    private final Class<? extends Writable> clazz;
+    private final MapFn<T, Object> mapFn;
+
+    public CollectionArrayMapFn(Class<? extends Writable> clazz,
+        MapFn<T, Object> mapFn) {
+      this.clazz = clazz;
+      this.mapFn = mapFn;
+    }
+
+    @Override
+    public void configure(Configuration conf) {
+      mapFn.configure(conf);
+    }
+
+    @Override
+    public void setConfigurationForTest(Configuration conf) {
+      mapFn.setConfigurationForTest(conf);
+    }
+    
+    @Override
+    public void initialize() {
+      mapFn.setContext(getContext());   
+    }
+    
+    @Override
+    public GenericArrayWritable map(Collection<T> input) {
+      GenericArrayWritable arrayWritable = new GenericArrayWritable(clazz);
+      Writable[] w = new Writable[input.size()];
+      int index = 0;
+      for (T in : input) {
+        w[index++] = ((Writable) mapFn.map(in));
+      }
+      arrayWritable.set(w);
+      return arrayWritable;
+    }
+  }
+
+  public static <T> WritableType<Collection<T>, GenericArrayWritable<T>> collections(PType<T> ptype) {
+    WritableType<T, ?> wt = (WritableType<T, ?>) ptype;
+    return new WritableType(Collection.class, GenericArrayWritable.class,
+        new ArrayCollectionMapFn(wt.getInputMapFn()), new CollectionArrayMapFn(
+            wt.getSerializationClass(), wt.getOutputMapFn()), ptype);
+  }
+
+  private static class MapInputMapFn<T> extends MapFn<TextMapWritable<Writable>, Map<String, T>> {
+    private final MapFn<Writable, T> mapFn;
+
+    public MapInputMapFn(MapFn<Writable, T> mapFn) {
+      this.mapFn = mapFn;
+    }
+
+    @Override
+    public void configure(Configuration conf) {
+      mapFn.configure(conf);
+    }
+
+    @Override
+    public void setConfigurationForTest(Configuration conf) {
+      mapFn.setConfigurationForTest(conf);
+    }
+
+    @Override
+    public void initialize() {
+      mapFn.setContext(getContext());
+    }
+
+    @Override
+    public Map<String, T> map(TextMapWritable<Writable> input) {
+      Map<String, T> out = Maps.newHashMap();
+      for (Map.Entry<Text, Writable> e : input.entrySet()) {
+        out.put(e.getKey().toString(), mapFn.map(e.getValue()));
+      }
+      return out;
+    }
+  }
+  
+  private static class MapOutputMapFn<T> extends MapFn<Map<String, T>, TextMapWritable<Writable>> {
+
+    private final Class<Writable> clazz;
+    private final MapFn<T, Writable> mapFn;
+
+    public MapOutputMapFn(Class<Writable> clazz, MapFn<T, Writable> mapFn) {
+      this.clazz = clazz;
+      this.mapFn = mapFn;
+    }
+
+    @Override
+    public void configure(Configuration conf) {
+      mapFn.configure(conf);
+    }
+
+    @Override
+    public void setConfigurationForTest(Configuration conf) {
+      mapFn.setConfigurationForTest(conf);
+    }
+
+    @Override
+    public void initialize() {
+      mapFn.setContext(getContext());
+    }
+
+    @Override
+    public TextMapWritable<Writable> map(Map<String, T> input) {
+      TextMapWritable<Writable> tmw = new TextMapWritable<Writable>(clazz);
+      for (Map.Entry<String, T> e : input.entrySet()) {
+        tmw.put(new Text(e.getKey()), mapFn.map(e.getValue()));
+      }
+      return tmw;
+    }	
+  }
+  
+  public static <T> WritableType<Map<String, T>, MapWritable> maps(PType<T> ptype) {
+	WritableType<T, ?> wt = (WritableType<T, ?>) ptype;
+    return new WritableType(Map.class, TextMapWritable.class,
+        new MapInputMapFn(wt.getInputMapFn()),
+        new MapOutputMapFn(wt.getSerializationClass(), wt.getOutputMapFn()), ptype);
+  }
+  
+  public static <T> PType<T> jsons(Class<T> clazz) {
+    return PTypes.jsonString(clazz, WritableTypeFamily.getInstance());  
+  }
+  
+  /**
+   * Perform a deep copy of a writable value.
+   * 
+   * @param value
+   *          The value to be copied
+   * @param writableClass
+   *          The Writable class of the value to be copied
+   * @return A fully detached deep copy of the input value
+   */
+  public static <T extends Writable> T deepCopy(T value, Class<T> writableClass) {
+    ByteArrayOutputStream byteOutStream = new ByteArrayOutputStream();
+    DataOutputStream dataOut = new DataOutputStream(byteOutStream);
+    T copiedValue = null;
+    try {
+      value.write(dataOut);
+      dataOut.flush();
+      ByteArrayInputStream byteInStream = new ByteArrayInputStream(byteOutStream.toByteArray());
+      DataInput dataInput = new DataInputStream(byteInStream);
+      copiedValue = writableClass.newInstance();
+      copiedValue.readFields(dataInput);
+    } catch (Exception e) {
+      throw new CrunchRuntimeException("Error while deep copying " + value, e);
+    }
+    return copiedValue;
+  }
+
+  // Not instantiable
+  private Writables() {
+  }
+}

http://git-wip-us.apache.org/repos/asf/incubator-crunch/blob/83acb813/crunch/src/main/java/org/apache/crunch/util/Collects.java
----------------------------------------------------------------------
diff --git a/crunch/src/main/java/org/apache/crunch/util/Collects.java b/crunch/src/main/java/org/apache/crunch/util/Collects.java
new file mode 100644
index 0000000..f5b07c4
--- /dev/null
+++ b/crunch/src/main/java/org/apache/crunch/util/Collects.java
@@ -0,0 +1,48 @@
+/**
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.crunch.util;
+
+import java.util.Collection;
+import java.util.Iterator;
+
+import com.google.common.collect.Lists;
+
+/**
+ * Utility functions for returning Collection objects backed by different types
+ * of implementations.
+ */
+public class Collects {
+  
+  public static <T> Collection<T> newArrayList() {
+    return Lists.newArrayList();
+  }
+
+  public static <T> Collection<T> newArrayList(T...elements) {
+    return Lists.newArrayList(elements);
+  }
+
+  public static <T> Collection<T> newArrayList(Iterable<? extends T> elements) {
+    return Lists.newArrayList(elements);
+  }
+
+  public static <T> Collection<T> newArrayList(Iterator<? extends T> elements) {
+    return Lists.newArrayList(elements);
+  }
+
+  private Collects() {}
+}

http://git-wip-us.apache.org/repos/asf/incubator-crunch/blob/83acb813/crunch/src/main/java/org/apache/crunch/util/DistCache.java
----------------------------------------------------------------------
diff --git a/crunch/src/main/java/org/apache/crunch/util/DistCache.java b/crunch/src/main/java/org/apache/crunch/util/DistCache.java
new file mode 100644
index 0000000..682e8f0
--- /dev/null
+++ b/crunch/src/main/java/org/apache/crunch/util/DistCache.java
@@ -0,0 +1,198 @@
+/**
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.crunch.util;
+
+import java.io.File;
+import java.io.IOException;
+import java.io.ObjectInputStream;
+import java.io.ObjectOutputStream;
+import java.net.URI;
+import java.net.URL;
+import java.net.URLDecoder;
+import java.util.Enumeration;
+
+import org.apache.hadoop.conf.Configuration;
+import org.apache.hadoop.filecache.DistributedCache;
+import org.apache.hadoop.fs.FileSystem;
+import org.apache.hadoop.fs.Path;
+
+import org.apache.crunch.impl.mr.run.CrunchRuntimeException;
+
+/**
+ * Provides functions for working with Hadoop's distributed cache. These include:
+ * <ul>
+ *   <li>
+ *     Functions for working with a job-specific distributed cache of objects, like the
+ *     serialized runtime nodes in a MapReduce.
+ *   </li>
+ *   <li>
+ *     Functions for adding library jars to the distributed cache, which will be added to the
+ *     classpath of MapReduce tasks.
+ *   </li>
+ * </ul>
+ */
+public class DistCache {
+
+  // Configuration key holding the paths of jars to export to the distributed cache.
+  private static final String TMPJARS_KEY = "tmpjars";
+
+  public static void write(Configuration conf, Path path, Object value) throws IOException {
+    ObjectOutputStream oos = new ObjectOutputStream(FileSystem.get(conf).create(path));
+    oos.writeObject(value);
+    oos.close();
+
+    DistributedCache.addCacheFile(path.toUri(), conf);
+  }
+
+  public static Object read(Configuration conf, Path path) throws IOException {
+    URI target = null;
+    for (URI uri : DistributedCache.getCacheFiles(conf)) {
+      if (uri.toString().equals(path.toString())) {
+        target = uri;
+        break;
+      }
+    }
+    Object value = null;
+    if (target != null) {
+      Path targetPath = new Path(target.toString());
+      ObjectInputStream ois = new ObjectInputStream(targetPath.getFileSystem(conf).open(targetPath));
+      try {
+        value = ois.readObject();
+      } catch (ClassNotFoundException e) {
+        throw new CrunchRuntimeException(e);
+      }
+      ois.close();
+    }
+    return value;
+  }
+
+  /**
+   * Adds the specified jar to the distributed cache of jobs using the provided configuration. The
+   * jar will be placed on the classpath of tasks run by the job.
+   *
+   * @param conf The configuration used to add the jar to the distributed cache.
+   * @param jarFile The jar file to add to the distributed cache.
+   * @throws IOException If the jar file does not exist or there is a problem accessing the file.
+   */
+  public static void addJarToDistributedCache(Configuration conf, File jarFile) throws IOException {
+    if (!jarFile.exists()) {
+      throw new IOException("Jar file: " + jarFile.getCanonicalPath() + " does not exist.");
+    }
+    if (!jarFile.getName().endsWith(".jar")) {
+      throw new IllegalArgumentException("File: " + jarFile.getCanonicalPath() + " is not a .jar "
+          + "file.");
+    }
+    // Get a qualified path for the jar.
+    FileSystem fileSystem = FileSystem.getLocal(conf);
+    Path jarPath = new Path(jarFile.getCanonicalPath());
+    String qualifiedPath = jarPath.makeQualified(fileSystem).toString();
+    // Add the jar to the configuration variable.
+    String jarConfiguration = conf.get(TMPJARS_KEY, "");
+    if (!jarConfiguration.isEmpty()) {
+      jarConfiguration += ",";
+    }
+    jarConfiguration += qualifiedPath;
+    conf.set(TMPJARS_KEY, jarConfiguration);
+  }
+
+  /**
+   * Adds the jar at the specified path to the distributed cache of jobs using the provided
+   * configuration. The jar will be placed on the classpath of tasks run by the job.
+   *
+   * @param conf The configuration used to add the jar to the distributed cache.
+   * @param jarFile The path to the jar file to add to the distributed cache.
+   * @throws IOException If the jar file does not exist or there is a problem accessing the file.
+   */
+  public static void addJarToDistributedCache(Configuration conf, String jarFile)
+      throws IOException {
+    addJarToDistributedCache(conf, new File(jarFile));
+  }
+
+  /**
+   * Finds the path to a jar that contains the class provided, if any. There is no guarantee that
+   * the jar returned will be the first on the classpath to contain the file. This method is
+   * basically lifted out of Hadoop's {@link org.apache.hadoop.mapred.JobConf} class.
+   *
+   * @param jarClass The class the jar file should contain.
+   * @return The path to a jar file that contains the class, or <code>null</code> if no such jar
+   *     exists.
+   * @throws IOException If there is a problem searching for the jar file.
+   */
+  public static String findContainingJar(Class jarClass) throws IOException {
+    ClassLoader loader = jarClass.getClassLoader();
+    String classFile = jarClass.getName().replaceAll("\\.", "/") + ".class";
+      for(Enumeration itr = loader.getResources(classFile); itr.hasMoreElements();) {
+        URL url = (URL) itr.nextElement();
+        if ("jar".equals(url.getProtocol())) {
+          String toReturn = url.getPath();
+          if (toReturn.startsWith("file:")) {
+            toReturn = toReturn.substring("file:".length());
+          }
+          // URLDecoder is a misnamed class, since it actually decodes
+          // x-www-form-urlencoded MIME type rather than actual
+          // URL encoding (which the file path has). Therefore it would
+          // decode +s to ' 's which is incorrect (spaces are actually
+          // either unencoded or encoded as "%20"). Replace +s first, so
+          // that they are kept sacred during the decoding process.
+          toReturn = toReturn.replaceAll("\\+", "%2B");
+          toReturn = URLDecoder.decode(toReturn, "UTF-8");
+          return toReturn.replaceAll("!.*$", "");
+        }
+      }
+    return null;
+  }
+
+  /**
+   * Adds all jars under the specified directory to the distributed cache of jobs using the
+   * provided configuration. The jars will be placed on the classpath of tasks run by the job.
+   * This method does not descend into subdirectories when adding jars.
+   *
+   * @param conf The configuration used to add jars to the distributed cache.
+   * @param jarDirectory A directory containing jar files to add to the distributed cache.
+   * @throws IOException If the directory does not exist or there is a problem accessing the
+   *     directory.
+   */
+  public static void addJarDirToDistributedCache(Configuration conf, File jarDirectory)
+      throws IOException {
+    if (!jarDirectory.exists() || !jarDirectory.isDirectory()) {
+      throw new IOException("Jar directory: " + jarDirectory.getCanonicalPath() + " does not "
+        + "exist or is not a directory.");
+    }
+    for (File file : jarDirectory.listFiles()) {
+      if (!file.isDirectory() && file.getName().endsWith(".jar")) {
+        addJarToDistributedCache(conf, file);
+      }
+    }
+  }
+
+  /**
+   * Adds all jars under the directory at the specified path to the distributed cache of jobs
+   * using the provided configuration.  The jars will be placed on the classpath of the tasks
+   * run by the job. This method does not descend into subdirectories when adding jars.
+   *
+   * @param conf The configuration used to add jars to the distributed cache.
+   * @param jarDirectory The path to a directory containing jar files to add to the distributed
+   *     cache.
+   * @throws IOException If the directory does not exist or there is a problem accessing the
+   *     directory.
+   */
+  public static void addJarDirToDistributedCache(Configuration conf, String jarDirectory)
+      throws IOException {
+    addJarDirToDistributedCache(conf, new File(jarDirectory));
+  }
+}

http://git-wip-us.apache.org/repos/asf/incubator-crunch/blob/83acb813/crunch/src/main/java/org/apache/crunch/util/PTypes.java
----------------------------------------------------------------------
diff --git a/crunch/src/main/java/org/apache/crunch/util/PTypes.java b/crunch/src/main/java/org/apache/crunch/util/PTypes.java
new file mode 100644
index 0000000..863b40f
--- /dev/null
+++ b/crunch/src/main/java/org/apache/crunch/util/PTypes.java
@@ -0,0 +1,259 @@
+/**
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.crunch.util;
+
+import java.math.BigInteger;
+import java.nio.ByteBuffer;
+
+import org.apache.hadoop.util.ReflectionUtils;
+import org.apache.thrift.TBase;
+import org.apache.thrift.TDeserializer;
+import org.apache.thrift.TException;
+import org.apache.thrift.TSerializer;
+import org.apache.thrift.protocol.TBinaryProtocol;
+import org.codehaus.jackson.map.ObjectMapper;
+import org.codehaus.jackson.smile.SmileFactory;
+
+import org.apache.crunch.MapFn;
+import org.apache.crunch.impl.mr.run.CrunchRuntimeException;
+import org.apache.crunch.types.PType;
+import org.apache.crunch.types.PTypeFamily;
+import com.google.protobuf.InvalidProtocolBufferException;
+import com.google.protobuf.Message;
+
+/**
+ * Utility functions for creating common types of derived PTypes, e.g., for JSON data,
+ * protocol buffers, and Thrift records.
+ *
+ */
+public class PTypes {
+
+  public static PType<BigInteger> bigInt(PTypeFamily typeFamily) {
+    return typeFamily.derived(BigInteger.class, BYTE_TO_BIGINT, BIGINT_TO_BYTE, typeFamily.bytes());  
+  }
+  
+  public static <T> PType<T> jsonString(Class<T> clazz, PTypeFamily typeFamily) {
+    return typeFamily.derived(clazz, new JacksonInputMapFn<T>(clazz),
+        new JacksonOutputMapFn<T>(), typeFamily.strings());
+  }
+
+  public static <T> PType<T> smile(Class<T> clazz, PTypeFamily typeFamily) {
+	return typeFamily.derived(clazz, new SmileInputMapFn<T>(clazz),
+	    new SmileOutputMapFn<T>(), typeFamily.bytes());
+  }
+  
+  public static <T extends Message> PType<T> protos(Class<T> clazz, PTypeFamily typeFamily) {
+    return typeFamily.derived(clazz, new ProtoInputMapFn<T>(clazz),
+        new ProtoOutputMapFn<T>(), typeFamily.bytes());
+  }
+  
+  public static <T extends TBase> PType<T> thrifts(Class<T> clazz, PTypeFamily typeFamily) {
+    return typeFamily.derived(clazz, new ThriftInputMapFn<T>(clazz),
+        new ThriftOutputMapFn<T>(), typeFamily.bytes());
+  }
+  
+  public static MapFn<ByteBuffer, BigInteger> BYTE_TO_BIGINT = new MapFn<ByteBuffer, BigInteger>() {
+    public BigInteger map(ByteBuffer input) {
+      return input == null ? null : new BigInteger(input.array());
+    }
+  };
+
+  public static MapFn<BigInteger, ByteBuffer> BIGINT_TO_BYTE = new MapFn<BigInteger, ByteBuffer>() {
+    public ByteBuffer map(BigInteger input) {
+      return input == null ? null : ByteBuffer.wrap(input.toByteArray());
+    }
+  };
+  
+  public static class SmileInputMapFn<T> extends MapFn<ByteBuffer, T> {
+
+    private final Class<T> clazz;
+    private transient ObjectMapper mapper;
+    
+    public SmileInputMapFn(Class<T> clazz) {
+      this.clazz = clazz;
+    }
+
+    @Override
+    public void initialize() {
+      this.mapper = new ObjectMapper(new SmileFactory());
+    }
+    
+	@Override
+	public T map(ByteBuffer input) {
+      try {
+        return mapper.readValue(input.array(), input.position(), input.limit(), clazz);
+      } catch (Exception e) {
+        throw new CrunchRuntimeException(e);
+      }
+	}
+  }
+  
+  public static class SmileOutputMapFn<T> extends MapFn<T, ByteBuffer> {
+    private transient ObjectMapper mapper;
+    
+    @Override
+    public void initialize() {
+      this.mapper = new ObjectMapper(new SmileFactory());
+    }
+    
+    @Override
+    public ByteBuffer map(T input) {
+      try {
+        return ByteBuffer.wrap(mapper.writeValueAsBytes(input));
+      } catch (Exception e) {
+        throw new CrunchRuntimeException(e);
+      }
+    }
+  }
+
+  public static class JacksonInputMapFn<T> extends MapFn<String, T> {
+    
+    private final Class<T> clazz;
+    private transient ObjectMapper mapper;
+    
+    public JacksonInputMapFn(Class<T> clazz) {
+      this.clazz = clazz;
+    }
+    
+    @Override
+    public void initialize() {
+      this.mapper = new ObjectMapper();
+    }
+    
+    @Override
+    public T map(String input) {
+      try {
+        return mapper.readValue(input, clazz);
+      } catch (Exception e) {
+        throw new CrunchRuntimeException(e);
+      }
+    } 
+  }
+  
+  public static class JacksonOutputMapFn<T> extends MapFn<T, String> {
+    
+    private transient ObjectMapper mapper;
+    
+    @Override
+    public void initialize() {
+      this.mapper = new ObjectMapper();
+    }
+    
+    @Override
+    public String map(T input) {
+      try {
+        return mapper.writeValueAsString(input);
+      } catch (Exception e) {
+        throw new CrunchRuntimeException(e);
+      }
+    }
+  }
+  
+  public static class ProtoInputMapFn<T extends Message> extends MapFn<ByteBuffer, T> {
+    
+    private final Class<T> clazz;
+    private transient T instance;
+    
+    public ProtoInputMapFn(Class<T> clazz) {
+      this.clazz = clazz;
+    }
+    
+    @Override
+    public void initialize() {
+      this.instance = ReflectionUtils.newInstance(clazz, getConfiguration());
+    }
+    
+    @Override
+    public T map(ByteBuffer bb) {
+      try {
+        return (T) instance.newBuilderForType().mergeFrom(
+            bb.array(), bb.position(), bb.limit()).build();
+      } catch (InvalidProtocolBufferException e) {
+        throw new CrunchRuntimeException(e);
+      }
+    }    
+  }
+  
+  public static class ProtoOutputMapFn<T extends Message> extends MapFn<T, ByteBuffer> {
+    
+    public ProtoOutputMapFn() {
+    }
+    
+    @Override
+    public ByteBuffer map(T proto) {
+      return ByteBuffer.wrap(proto.toByteArray());
+    }    
+  }
+
+  public static class ThriftInputMapFn<T extends TBase> extends MapFn<ByteBuffer, T> {
+
+    private final Class<T> clazz;
+    private transient T instance;
+    private transient TDeserializer deserializer;
+    private transient byte[] bytes;
+    
+    public ThriftInputMapFn(Class<T> clazz) {
+      this.clazz = clazz;
+    }
+    
+    @Override
+    public void initialize() {
+      this.instance = ReflectionUtils.newInstance(clazz, getConfiguration());
+      this.deserializer = new TDeserializer(new TBinaryProtocol.Factory());
+      this.bytes = new byte[0];
+    }
+    
+    @Override
+    public T map(ByteBuffer bb) {
+      T next = (T) instance.deepCopy();
+      int len = bb.limit() - bb.position();
+      if (len != bytes.length) {
+        bytes = new byte[len];
+      }
+      System.arraycopy(bb.array(), bb.position(), bytes, 0, len);
+      try {
+        deserializer.deserialize(next, bytes);
+      } catch (TException e) {
+        throw new CrunchRuntimeException(e);
+      }
+      return next;
+    }    
+  }
+  
+  public static class ThriftOutputMapFn<T extends TBase> extends MapFn<T, ByteBuffer> {
+
+    private transient TSerializer serializer;
+    
+    public ThriftOutputMapFn() {
+    }
+    
+    @Override
+    public void initialize() {
+      this.serializer = new TSerializer(new TBinaryProtocol.Factory());
+    }
+    
+    @Override
+    public ByteBuffer map(T t) {
+      try {
+        return ByteBuffer.wrap(serializer.serialize(t));
+      } catch (TException e) {
+        throw new CrunchRuntimeException(e);
+      }
+    }    
+  }
+}

http://git-wip-us.apache.org/repos/asf/incubator-crunch/blob/83acb813/crunch/src/main/java/org/apache/crunch/util/Protos.java
----------------------------------------------------------------------
diff --git a/crunch/src/main/java/org/apache/crunch/util/Protos.java b/crunch/src/main/java/org/apache/crunch/util/Protos.java
new file mode 100644
index 0000000..2cda492
--- /dev/null
+++ b/crunch/src/main/java/org/apache/crunch/util/Protos.java
@@ -0,0 +1,150 @@
+/**
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.crunch.util;
+
+import java.util.Iterator;
+import java.util.List;
+
+import org.apache.hadoop.util.ReflectionUtils;
+
+import org.apache.crunch.DoFn;
+import org.apache.crunch.Emitter;
+import org.apache.crunch.MapFn;
+import com.google.common.base.Splitter;
+import com.google.protobuf.Descriptors.FieldDescriptor;
+import com.google.protobuf.Message;
+import com.google.protobuf.Message.Builder;
+
+/**
+ * Utility functions for working with protocol buffers in Crunch.
+ */
+public class Protos {
+
+  public static <M extends Message, K> MapFn<M, K> extractKey(String fieldName) {
+    return new ExtractKeyFn<M, K>(fieldName);
+  }
+  
+  public static <M extends Message> DoFn<String, M> lineParser(String sep, Class<M> msgClass) {
+    return new TextToProtoFn<M>(sep, msgClass);  
+  }
+  
+  public static class ExtractKeyFn<M extends Message, K> extends MapFn<M, K> {
+    
+    private final String fieldName;
+    
+    private transient FieldDescriptor fd;
+    
+    public ExtractKeyFn(String fieldName) {
+      this.fieldName = fieldName;
+    }
+    
+    @Override
+    public K map(M input) {
+      if (input == null) {
+        throw new IllegalArgumentException("Null inputs not supported by Protos.ExtractKeyFn");
+      } else if (fd == null) {
+        fd = input.getDescriptorForType().findFieldByName(fieldName);
+        if (fd == null) {
+          throw new IllegalStateException(
+              "Could not find field: " + fieldName + " in message: " + input);
+        }
+      }
+      return (K) input.getField(fd);
+    }
+    
+  }
+  
+  public static class TextToProtoFn<M extends Message> extends DoFn<String, M> {
+    
+    private final String sep;
+    private final Class<M> msgClass;
+    
+    private transient M msgInstance;
+    private transient List<FieldDescriptor> fields;
+    private transient Splitter splitter;
+    
+    enum ParseErrors { TOTAL, NUMBER_FORMAT };
+    
+    public TextToProtoFn(String sep, Class<M> msgClass) {
+      this.sep = sep;
+      this.msgClass = msgClass;
+    }
+    
+    @Override
+    public void initialize() {
+      this.msgInstance = ReflectionUtils.newInstance(msgClass, getConfiguration());
+      this.fields = msgInstance.getDescriptorForType().getFields();
+      this.splitter = Splitter.on(sep);
+    }
+
+    @Override
+    public void process(String input, Emitter<M> emitter) {
+      if (input != null && !input.isEmpty()) {
+        Builder b = msgInstance.newBuilderForType();
+        Iterator<String> iter = splitter.split(input).iterator();
+        boolean parseError = false;
+        for (FieldDescriptor fd : fields) {
+          if (iter.hasNext()) {
+            String value = iter.next();
+            if (value != null && !value.isEmpty()) {
+              Object parsedValue = null;
+              try {
+                switch (fd.getJavaType()) {
+                case STRING:
+                  parsedValue = value;
+                  break;
+                case INT:
+                  parsedValue = Integer.valueOf(value);
+                  break;
+                case LONG:
+                  parsedValue = Long.valueOf(value);
+                  break;
+                case FLOAT:
+                  parsedValue = Float.valueOf(value);
+                  break;
+                case DOUBLE:
+                  parsedValue = Double.valueOf(value);
+                  break;
+                case BOOLEAN:
+                  parsedValue = Boolean.valueOf(value);
+                  break;
+                case ENUM:
+                  parsedValue = fd.getEnumType().findValueByName(value);
+                  break;
+                }
+                b.setField(fd, parsedValue);
+              } catch (NumberFormatException nfe) {
+                increment(ParseErrors.NUMBER_FORMAT);
+                parseError = true;
+                break;
+              }
+            }
+          }
+        }
+        
+        if (parseError) {
+          increment(ParseErrors.TOTAL);
+        } else {
+          emitter.emit((M) b.build());
+        }
+      }
+    }
+  }
+  
+  
+}

http://git-wip-us.apache.org/repos/asf/incubator-crunch/blob/83acb813/crunch/src/main/java/org/apache/crunch/util/Tuples.java
----------------------------------------------------------------------
diff --git a/crunch/src/main/java/org/apache/crunch/util/Tuples.java b/crunch/src/main/java/org/apache/crunch/util/Tuples.java
new file mode 100644
index 0000000..b8eb3b9
--- /dev/null
+++ b/crunch/src/main/java/org/apache/crunch/util/Tuples.java
@@ -0,0 +1,151 @@
+/**
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.crunch.util;
+
+import java.util.Iterator;
+import java.util.List;
+
+import org.apache.crunch.Pair;
+import org.apache.crunch.Tuple3;
+import org.apache.crunch.Tuple4;
+import org.apache.crunch.TupleN;
+import com.google.common.collect.Lists;
+import com.google.common.collect.UnmodifiableIterator;
+
+/**
+ * Utilities for working with subclasses of the {@code Tuple} interface.
+ *
+ */
+public class Tuples {
+
+  private static abstract class TuplifyIterator<T> extends UnmodifiableIterator<T> {
+    protected List<Iterator<?>> iterators;
+    
+    public TuplifyIterator(Iterator<?>...iterators) {
+      this.iterators = Lists.newArrayList(iterators);
+    }
+    
+    @Override
+    public boolean hasNext() {
+      for (Iterator<?> iter : iterators) {
+        if (!iter.hasNext()) {
+          return false;
+        }
+      }
+      return true;
+    }
+    
+    protected Object next(int index) {
+      return iterators.get(index).next();
+    }
+  }
+  
+  public static class PairIterable<S, T> implements Iterable<Pair<S, T>> {
+    private final Iterable<S> first;
+    private final Iterable<T> second;
+    
+    public PairIterable(Iterable<S> first, Iterable<T> second) {
+      this.first = first;
+      this.second = second;
+    }
+    
+    @Override
+    public Iterator<Pair<S, T>> iterator() {
+      return new TuplifyIterator<Pair<S, T>>(first.iterator(), second.iterator()) {
+        @Override
+        public Pair<S, T> next() {
+          return Pair.of((S) next(0), (T) next(1));
+        }
+      };
+    }   
+  }
+  
+  public static class TripIterable<A, B, C> implements Iterable<Tuple3<A, B, C>> {
+    private final Iterable<A> first;
+    private final Iterable<B> second;
+    private final Iterable<C> third;
+    
+    public TripIterable(Iterable<A> first, Iterable<B> second, Iterable<C> third) {
+      this.first = first;
+      this.second = second;
+      this.third = third;
+    }
+    
+    @Override
+    public Iterator<Tuple3<A, B, C>> iterator() {
+      return new TuplifyIterator<Tuple3<A, B, C>>(first.iterator(), second.iterator(),
+          third.iterator()) {
+        @Override
+        public Tuple3<A, B, C> next() {
+          return new Tuple3<A, B, C>((A) next(0), (B) next(1), (C) next(2));
+        }
+      };
+    }   
+  }
+  
+  public static class QuadIterable<A, B, C, D> implements Iterable<Tuple4<A, B, C, D>> {
+    private final Iterable<A> first;
+    private final Iterable<B> second;
+    private final Iterable<C> third;
+    private final Iterable<D> fourth;
+    
+    public QuadIterable(Iterable<A> first, Iterable<B> second, Iterable<C> third,
+        Iterable<D> fourth) {
+      this.first = first;
+      this.second = second;
+      this.third = third;
+      this.fourth = fourth;
+    }
+    
+    @Override
+    public Iterator<Tuple4<A, B, C, D>> iterator() {
+      return new TuplifyIterator<Tuple4<A, B, C, D>>(first.iterator(), second.iterator(),
+          third.iterator(), fourth.iterator()) {
+        @Override
+        public Tuple4<A, B, C, D> next() {
+          return new Tuple4<A, B, C, D>((A) next(0), (B) next(1), (C) next(2), (D) next(3));
+        }
+      };
+    }   
+  }
+  
+  public static class TupleNIterable implements Iterable<TupleN> {
+    private final Iterator<?>[] iters;
+    
+    public TupleNIterable(Iterable<?>... iterables) {
+      this.iters = new Iterator[iterables.length];
+      for (int i = 0; i < iters.length; i++) {
+        iters[i] = iterables[i].iterator();
+      }
+    }
+    
+    @Override
+    public Iterator<TupleN> iterator() {
+      return new TuplifyIterator<TupleN>(iters) {
+        @Override
+        public TupleN next() {
+          Object[] values = new Object[iters.length];
+          for (int i = 0; i < values.length; i++) {
+            values[i] = next(i);
+          }
+          return new TupleN(values);
+        }
+      };
+    }
+  }
+}

http://git-wip-us.apache.org/repos/asf/incubator-crunch/blob/83acb813/crunch/src/main/java/org/apache/hadoop/mapreduce/lib/jobcontrol/CrunchControlledJob.java
----------------------------------------------------------------------
diff --git a/crunch/src/main/java/org/apache/hadoop/mapreduce/lib/jobcontrol/CrunchControlledJob.java b/crunch/src/main/java/org/apache/hadoop/mapreduce/lib/jobcontrol/CrunchControlledJob.java
new file mode 100644
index 0000000..6756dbb
--- /dev/null
+++ b/crunch/src/main/java/org/apache/hadoop/mapreduce/lib/jobcontrol/CrunchControlledJob.java
@@ -0,0 +1,338 @@
+/**
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.hadoop.mapreduce.lib.jobcontrol;
+
+import java.io.IOException;
+import java.util.ArrayList;
+import java.util.List;
+
+import org.apache.hadoop.conf.Configuration;
+import org.apache.hadoop.fs.FileSystem;
+import org.apache.hadoop.fs.Path;
+import org.apache.hadoop.mapreduce.Job;
+import org.apache.hadoop.mapreduce.JobID;
+import org.apache.hadoop.mapreduce.lib.input.FileInputFormat;
+import org.apache.hadoop.util.StringUtils;
+
+/**
+ * This class encapsulates a MapReduce job and its dependency. It monitors the
+ * states of the depending jobs and updates the state of this job. A job starts
+ * in the WAITING state. If it does not have any depending jobs, or all of the
+ * depending jobs are in SUCCESS state, then the job state will become READY. If
+ * any depending jobs fail, the job will fail too. When in READY state, the job
+ * can be submitted to Hadoop for execution, with the state changing into
+ * RUNNING state. From RUNNING state, the job can get into SUCCESS or FAILED
+ * state, depending the status of the job execution.
+ */
+public class CrunchControlledJob {
+
+  // A job will be in one of the following states
+  public static enum State {
+    SUCCESS, WAITING, RUNNING, READY, FAILED, DEPENDENT_FAILED
+  };
+
+  public static final String CREATE_DIR = "mapreduce.jobcontrol.createdir.ifnotexist";
+  protected State state;
+  protected Job job; // mapreduce job to be executed.
+  // some info for human consumption, e.g. the reason why the job failed
+  protected String message;
+  private String controlID; // assigned and used by JobControl class
+  // the jobs the current job depends on
+  private List<CrunchControlledJob> dependingJobs;
+
+  /**
+   * Construct a job.
+   * 
+   * @param job
+   *          a mapreduce job to be executed.
+   * @param dependingJobs
+   *          an array of jobs the current job depends on
+   */
+  public CrunchControlledJob(Job job, List<CrunchControlledJob> dependingJobs)
+      throws IOException {
+    this.job = job;
+    this.dependingJobs = dependingJobs;
+    this.state = State.WAITING;
+    this.controlID = "unassigned";
+    this.message = "just initialized";
+  }
+
+  /**
+   * Construct a job.
+   * 
+   * @param conf
+   *          mapred job configuration representing a job to be executed.
+   * @throws IOException
+   */
+  public CrunchControlledJob(Configuration conf) throws IOException {
+    this(new Job(conf), null);
+  }
+
+  @Override
+  public String toString() {
+    StringBuffer sb = new StringBuffer();
+    sb.append("job name:\t").append(this.job.getJobName()).append("\n");
+    sb.append("job id:\t").append(this.controlID).append("\n");
+    sb.append("job state:\t").append(this.state).append("\n");
+    sb.append("job mapred id:\t").append(this.job.getJobID()).append("\n");
+    sb.append("job message:\t").append(this.message).append("\n");
+
+    if (this.dependingJobs == null || this.dependingJobs.size() == 0) {
+      sb.append("job has no depending job:\t").append("\n");
+    } else {
+      sb.append("job has ").append(this.dependingJobs.size())
+          .append(" dependeng jobs:\n");
+      for (int i = 0; i < this.dependingJobs.size(); i++) {
+        sb.append("\t depending job ").append(i).append(":\t");
+        sb.append((this.dependingJobs.get(i)).getJobName()).append("\n");
+      }
+    }
+    return sb.toString();
+  }
+
+  /**
+   * @return the job name of this job
+   */
+  public String getJobName() {
+    return job.getJobName();
+  }
+
+  /**
+   * Set the job name for this job.
+   * 
+   * @param jobName
+   *          the job name
+   */
+  public void setJobName(String jobName) {
+    job.setJobName(jobName);
+  }
+
+  /**
+   * @return the job ID of this job assigned by JobControl
+   */
+  public String getJobID() {
+    return this.controlID;
+  }
+
+  /**
+   * Set the job ID for this job.
+   * 
+   * @param id
+   *          the job ID
+   */
+  public void setJobID(String id) {
+    this.controlID = id;
+  }
+
+  /**
+   * @return the mapred ID of this job as assigned by the mapred framework.
+   */
+  public JobID getMapredJobID() {
+    return this.job.getJobID();
+  }
+
+  /**
+   * @return the mapreduce job
+   */
+  public synchronized Job getJob() {
+    return this.job;
+  }
+
+  /**
+   * Set the mapreduce job
+   * 
+   * @param job
+   *          the mapreduce job for this job.
+   */
+  public synchronized void setJob(Job job) {
+    this.job = job;
+  }
+
+  /**
+   * @return the state of this job
+   */
+  public synchronized State getJobState() {
+    return this.state;
+  }
+
+  /**
+   * Set the state for this job.
+   * 
+   * @param state
+   *          the new state for this job.
+   */
+  protected synchronized void setJobState(State state) {
+    this.state = state;
+  }
+
+  /**
+   * @return the message of this job
+   */
+  public synchronized String getMessage() {
+    return this.message;
+  }
+
+  /**
+   * Set the message for this job.
+   * 
+   * @param message
+   *          the message for this job.
+   */
+  public synchronized void setMessage(String message) {
+    this.message = message;
+  }
+
+  /**
+   * @return the depending jobs of this job
+   */
+  public List<CrunchControlledJob> getDependentJobs() {
+    return this.dependingJobs;
+  }
+
+  /**
+   * Add a job to this jobs' dependency list. Dependent jobs can only be added
+   * while a Job is waiting to run, not during or afterwards.
+   * 
+   * @param dependingJob
+   *          Job that this Job depends on.
+   * @return <tt>true</tt> if the Job was added.
+   */
+  public synchronized boolean addDependingJob(CrunchControlledJob dependingJob) {
+    if (this.state == State.WAITING) { // only allowed to add jobs when waiting
+      if (this.dependingJobs == null) {
+        this.dependingJobs = new ArrayList<CrunchControlledJob>();
+      }
+      return this.dependingJobs.add(dependingJob);
+    } else {
+      return false;
+    }
+  }
+
+  /**
+   * @return true if this job is in a complete state
+   */
+  public synchronized boolean isCompleted() {
+    return this.state == State.FAILED || this.state == State.DEPENDENT_FAILED
+        || this.state == State.SUCCESS;
+  }
+
+  /**
+   * @return true if this job is in READY state
+   */
+  public synchronized boolean isReady() {
+    return this.state == State.READY;
+  }
+
+  public void killJob() throws IOException, InterruptedException {
+    job.killJob();
+  }
+
+  /**
+   * Check the state of this running job. The state may remain the same, become
+   * SUCCESS or FAILED.
+   */
+  protected void checkRunningState() throws IOException, InterruptedException {
+    try {
+      if (job.isComplete()) {
+        if (job.isSuccessful()) {
+          this.state = State.SUCCESS;
+        } else {
+          this.state = State.FAILED;
+          this.message = "Job failed!";
+        }
+      }
+    } catch (IOException ioe) {
+      this.state = State.FAILED;
+      this.message = StringUtils.stringifyException(ioe);
+      try {
+        if (job != null) {
+          job.killJob();
+        }
+      } catch (IOException e) {
+      }
+    }
+  }
+
+  /**
+   * Check and update the state of this job. The state changes depending on its
+   * current state and the states of the depending jobs.
+   */
+  synchronized State checkState() throws IOException, InterruptedException {
+    if (this.state == State.RUNNING) {
+      checkRunningState();
+    }
+    if (this.state != State.WAITING) {
+      return this.state;
+    }
+    if (this.dependingJobs == null || this.dependingJobs.size() == 0) {
+      this.state = State.READY;
+      return this.state;
+    }
+    CrunchControlledJob pred = null;
+    int n = this.dependingJobs.size();
+    for (int i = 0; i < n; i++) {
+      pred = this.dependingJobs.get(i);
+      State s = pred.checkState();
+      if (s == State.WAITING || s == State.READY || s == State.RUNNING) {
+        break; // a pred is still not completed, continue in WAITING
+        // state
+      }
+      if (s == State.FAILED || s == State.DEPENDENT_FAILED) {
+        this.state = State.DEPENDENT_FAILED;
+        this.message = "depending job " + i + " with jobID " + pred.getJobID()
+            + " failed. " + pred.getMessage();
+        break;
+      }
+      // pred must be in success state
+      if (i == n - 1) {
+        this.state = State.READY;
+      }
+    }
+
+    return this.state;
+  }
+
+  /**
+   * Submit this job to mapred. The state becomes RUNNING if submission is
+   * successful, FAILED otherwise.
+   */
+  protected synchronized void submit() {
+    try {
+      Configuration conf = job.getConfiguration();
+      if (conf.getBoolean(CREATE_DIR, false)) {
+        FileSystem fs = FileSystem.get(conf);
+        Path inputPaths[] = FileInputFormat.getInputPaths(job);
+        for (int i = 0; i < inputPaths.length; i++) {
+          if (!fs.exists(inputPaths[i])) {
+            try {
+              fs.mkdirs(inputPaths[i]);
+            } catch (IOException e) {
+
+            }
+          }
+        }
+      }
+      job.submit();
+      this.state = State.RUNNING;
+    } catch (Exception ioe) {
+      this.state = State.FAILED;
+      this.message = StringUtils.stringifyException(ioe);
+    }
+  }
+
+}

http://git-wip-us.apache.org/repos/asf/incubator-crunch/blob/83acb813/crunch/src/main/java/org/apache/hadoop/mapreduce/lib/jobcontrol/CrunchJobControl.java
----------------------------------------------------------------------
diff --git a/crunch/src/main/java/org/apache/hadoop/mapreduce/lib/jobcontrol/CrunchJobControl.java b/crunch/src/main/java/org/apache/hadoop/mapreduce/lib/jobcontrol/CrunchJobControl.java
new file mode 100644
index 0000000..7fa61d3
--- /dev/null
+++ b/crunch/src/main/java/org/apache/hadoop/mapreduce/lib/jobcontrol/CrunchJobControl.java
@@ -0,0 +1,297 @@
+/**
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.hadoop.mapreduce.lib.jobcontrol;
+
+import java.io.IOException;
+import java.util.ArrayList;
+import java.util.Collection;
+import java.util.Hashtable;
+import java.util.List;
+import java.util.Map;
+
+import org.apache.hadoop.mapreduce.lib.jobcontrol.CrunchControlledJob.State;
+
+/**
+ * This class encapsulates a set of MapReduce jobs and its dependency.
+ * 
+ * It tracks the states of the jobs by placing them into different tables
+ * according to their states.
+ * 
+ * This class provides APIs for the client app to add a job to the group and to
+ * get the jobs in the group in different states. When a job is added, an ID
+ * unique to the group is assigned to the job.
+ * 
+ * This class has a thread that submits jobs when they become ready, monitors
+ * the states of the running jobs, and updates the states of jobs based on the
+ * state changes of their depending jobs states. The class provides APIs for
+ * suspending/resuming the thread, and for stopping the thread.
+ * 
+ * TODO This is mostly a copy of the JobControl class in Hadoop MapReduce core. 
+ * Once the location and interface of the class are more stable in CDH, this class 
+ * should be removed completely and be based on the hadoop-core class.
+ */
+public class CrunchJobControl implements Runnable {
+
+  // The thread can be in one of the following state
+  public static enum ThreadState {
+    RUNNING, SUSPENDED, STOPPED, STOPPING, READY
+  };
+
+  private ThreadState runnerState; // the thread state
+
+  private Map<String, CrunchControlledJob> waitingJobs;
+  private Map<String, CrunchControlledJob> readyJobs;
+  private Map<String, CrunchControlledJob> runningJobs;
+  private Map<String, CrunchControlledJob> successfulJobs;
+  private Map<String, CrunchControlledJob> failedJobs;
+
+  private long nextJobID;
+  private String groupName;
+
+  /**
+   * Construct a job control for a group of jobs.
+   * 
+   * @param groupName
+   *          a name identifying this group
+   */
+  public CrunchJobControl(String groupName) {
+    this.waitingJobs = new Hashtable<String, CrunchControlledJob>();
+    this.readyJobs = new Hashtable<String, CrunchControlledJob>();
+    this.runningJobs = new Hashtable<String, CrunchControlledJob>();
+    this.successfulJobs = new Hashtable<String, CrunchControlledJob>();
+    this.failedJobs = new Hashtable<String, CrunchControlledJob>();
+    this.nextJobID = -1;
+    this.groupName = groupName;
+    this.runnerState = ThreadState.READY;
+  }
+
+  private static List<CrunchControlledJob> toList(Map<String, CrunchControlledJob> jobs) {
+    ArrayList<CrunchControlledJob> retv = new ArrayList<CrunchControlledJob>();
+    synchronized (jobs) {
+      for (CrunchControlledJob job : jobs.values()) {
+        retv.add(job);
+      }
+    }
+    return retv;
+  }
+
+  /**
+   * @return the jobs in the waiting state
+   */
+  public List<CrunchControlledJob> getWaitingJobList() {
+    return toList(this.waitingJobs);
+  }
+
+  /**
+   * @return the jobs in the running state
+   */
+  public List<CrunchControlledJob> getRunningJobList() {
+    return toList(this.runningJobs);
+  }
+
+  /**
+   * @return the jobs in the ready state
+   */
+  public List<CrunchControlledJob> getReadyJobsList() {
+    return toList(this.readyJobs);
+  }
+
+  /**
+   * @return the jobs in the success state
+   */
+  public List<CrunchControlledJob> getSuccessfulJobList() {
+    return toList(this.successfulJobs);
+  }
+
+  public List<CrunchControlledJob> getFailedJobList() {
+    return toList(this.failedJobs);
+  }
+
+  private String getNextJobID() {
+    nextJobID += 1;
+    return this.groupName + this.nextJobID;
+  }
+
+  private static void addToQueue(CrunchControlledJob aJob,
+      Map<String, CrunchControlledJob> queue) {
+    synchronized (queue) {
+      queue.put(aJob.getJobID(), aJob);
+    }
+  }
+
+  private void addToQueue(CrunchControlledJob aJob) {
+    Map<String, CrunchControlledJob> queue = getQueue(aJob.getJobState());
+    addToQueue(aJob, queue);
+  }
+
+  private Map<String, CrunchControlledJob> getQueue(State state) {
+    Map<String, CrunchControlledJob> retv = null;
+    if (state == State.WAITING) {
+      retv = this.waitingJobs;
+    } else if (state == State.READY) {
+      retv = this.readyJobs;
+    } else if (state == State.RUNNING) {
+      retv = this.runningJobs;
+    } else if (state == State.SUCCESS) {
+      retv = this.successfulJobs;
+    } else if (state == State.FAILED || state == State.DEPENDENT_FAILED) {
+      retv = this.failedJobs;
+    }
+    return retv;
+  }
+
+  /**
+   * Add a new job.
+   * 
+   * @param aJob
+   *          the new job
+   */
+  synchronized public String addJob(CrunchControlledJob aJob) {
+    String id = this.getNextJobID();
+    aJob.setJobID(id);
+    aJob.setJobState(State.WAITING);
+    this.addToQueue(aJob);
+    return id;
+  }
+
+  /**
+   * Add a collection of jobs
+   * 
+   * @param jobs
+   */
+  public void addJobCollection(Collection<CrunchControlledJob> jobs) {
+    for (CrunchControlledJob job : jobs) {
+      addJob(job);
+    }
+  }
+
+  /**
+   * @return the thread state
+   */
+  public ThreadState getThreadState() {
+    return this.runnerState;
+  }
+
+  /**
+   * set the thread state to STOPPING so that the thread will stop when it wakes
+   * up.
+   */
+  public void stop() {
+    this.runnerState = ThreadState.STOPPING;
+  }
+
+  /**
+   * suspend the running thread
+   */
+  public void suspend() {
+    if (this.runnerState == ThreadState.RUNNING) {
+      this.runnerState = ThreadState.SUSPENDED;
+    }
+  }
+
+  /**
+   * resume the suspended thread
+   */
+  public void resume() {
+    if (this.runnerState == ThreadState.SUSPENDED) {
+      this.runnerState = ThreadState.RUNNING;
+    }
+  }
+
+  synchronized private void checkRunningJobs() throws IOException,
+      InterruptedException {
+
+    Map<String, CrunchControlledJob> oldJobs = null;
+    oldJobs = this.runningJobs;
+    this.runningJobs = new Hashtable<String, CrunchControlledJob>();
+
+    for (CrunchControlledJob nextJob : oldJobs.values()) {
+      nextJob.checkState();
+      this.addToQueue(nextJob);
+    }
+  }
+
+  synchronized private void checkWaitingJobs() throws IOException,
+      InterruptedException {
+    Map<String, CrunchControlledJob> oldJobs = null;
+    oldJobs = this.waitingJobs;
+    this.waitingJobs = new Hashtable<String, CrunchControlledJob>();
+
+    for (CrunchControlledJob nextJob : oldJobs.values()) {
+      nextJob.checkState();
+      this.addToQueue(nextJob);
+    }
+  }
+
+  synchronized private void startReadyJobs() {
+    Map<String, CrunchControlledJob> oldJobs = null;
+    oldJobs = this.readyJobs;
+    this.readyJobs = new Hashtable<String, CrunchControlledJob>();
+
+    for (CrunchControlledJob nextJob : oldJobs.values()) {
+      // Submitting Job to Hadoop
+      nextJob.submit();
+      this.addToQueue(nextJob);
+    }
+  }
+
+  synchronized public boolean allFinished() {
+    return this.waitingJobs.size() == 0 && this.readyJobs.size() == 0
+        && this.runningJobs.size() == 0;
+  }
+
+  /**
+   * The main loop for the thread. The loop does the following: Check the states
+   * of the running jobs Update the states of waiting jobs Submit the jobs in
+   * ready state
+   */
+  public void run() {
+    this.runnerState = ThreadState.RUNNING;
+    while (true) {
+      while (this.runnerState == ThreadState.SUSPENDED) {
+        try {
+          Thread.sleep(5000);
+        } catch (Exception e) {
+
+        }
+      }
+      try {
+        checkRunningJobs();
+        checkWaitingJobs();
+        startReadyJobs();
+      } catch (Exception e) {
+        this.runnerState = ThreadState.STOPPED;
+      }
+      if (this.runnerState != ThreadState.RUNNING
+          && this.runnerState != ThreadState.SUSPENDED) {
+        break;
+      }
+      try {
+        Thread.sleep(5000);
+      } catch (Exception e) {
+
+      }
+      if (this.runnerState != ThreadState.RUNNING
+          && this.runnerState != ThreadState.SUSPENDED) {
+        break;
+      }
+    }
+    this.runnerState = ThreadState.STOPPED;
+  }
+
+}

http://git-wip-us.apache.org/repos/asf/incubator-crunch/blob/83acb813/crunch/src/main/java/org/apache/hadoop/mapreduce/lib/output/CrunchMultipleOutputs.java
----------------------------------------------------------------------
diff --git a/crunch/src/main/java/org/apache/hadoop/mapreduce/lib/output/CrunchMultipleOutputs.java b/crunch/src/main/java/org/apache/hadoop/mapreduce/lib/output/CrunchMultipleOutputs.java
new file mode 100644
index 0000000..10d033f
--- /dev/null
+++ b/crunch/src/main/java/org/apache/hadoop/mapreduce/lib/output/CrunchMultipleOutputs.java
@@ -0,0 +1,473 @@
+/**
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.hadoop.mapreduce.lib.output;
+
+import java.io.IOException;
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.HashMap;
+import java.util.HashSet;
+import java.util.List;
+import java.util.Map;
+import java.util.Set;
+import java.util.StringTokenizer;
+
+import org.apache.hadoop.conf.Configuration;
+import org.apache.hadoop.mapreduce.Job;
+import org.apache.hadoop.mapreduce.JobContext;
+import org.apache.hadoop.mapreduce.OutputFormat;
+import org.apache.hadoop.mapreduce.RecordWriter;
+import org.apache.hadoop.mapreduce.TaskAttemptContext;
+import org.apache.hadoop.mapreduce.TaskInputOutputContext;
+import org.apache.hadoop.util.ReflectionUtils;
+
+import org.apache.crunch.impl.mr.run.TaskAttemptContextFactory;
+
+/**
+ * The MultipleOutputs class simplifies writing output data 
+ * to multiple outputs
+ * 
+ * <p> 
+ * Case one: writing to additional outputs other than the job default output.
+ *
+ * Each additional output, or named output, may be configured with its own
+ * <code>OutputFormat</code>, with its own key class and with its own value
+ * class.
+ * 
+ * <p>
+ * Case two: to write data to different files provided by user
+ * </p>
+ * 
+ * <p>
+ * MultipleOutputs supports counters, by default they are disabled. The 
+ * counters group is the {@link CrunchMultipleOutputs} class name. The names of the 
+ * counters are the same as the output name. These count the number records 
+ * written to each output name.
+ * </p>
+ * 
+ * Usage pattern for job submission:
+ * <pre>
+ *
+ * Job job = new Job();
+ *
+ * FileInputFormat.setInputPath(job, inDir);
+ * FileOutputFormat.setOutputPath(job, outDir);
+ *
+ * job.setMapperClass(MOMap.class);
+ * job.setReducerClass(MOReduce.class);
+ * ...
+ *
+ * // Defines additional single text based output 'text' for the job
+ * MultipleOutputs.addNamedOutput(job, "text", TextOutputFormat.class,
+ * LongWritable.class, Text.class);
+ *
+ * // Defines additional sequence-file based output 'sequence' for the job
+ * MultipleOutputs.addNamedOutput(job, "seq",
+ *   SequenceFileOutputFormat.class,
+ *   LongWritable.class, Text.class);
+ * ...
+ *
+ * job.waitForCompletion(true);
+ * ...
+ * </pre>
+ * <p>
+ * Usage in Reducer:
+ * <pre>
+ * <K, V> String generateFileName(K k, V v) {
+ *   return k.toString() + "_" + v.toString();
+ * }
+ * 
+ * public class MOReduce extends
+ *   Reducer&lt;WritableComparable, Writable,WritableComparable, Writable&gt; {
+ * private MultipleOutputs mos;
+ * public void setup(Context context) {
+ * ...
+ * mos = new MultipleOutputs(context);
+ * }
+ *
+ * public void reduce(WritableComparable key, Iterator&lt;Writable&gt; values,
+ * Context context)
+ * throws IOException {
+ * ...
+ * mos.write("text", , key, new Text("Hello"));
+ * mos.write("seq", LongWritable(1), new Text("Bye"), "seq_a");
+ * mos.write("seq", LongWritable(2), key, new Text("Chau"), "seq_b");
+ * mos.write(key, new Text("value"), generateFileName(key, new Text("value")));
+ * ...
+ * }
+ *
+ * public void cleanup(Context) throws IOException {
+ * mos.close();
+ * ...
+ * }
+ *
+ * }
+ * </pre>
+ */
+public class CrunchMultipleOutputs<KEYOUT, VALUEOUT> {
+
+  private static final String MULTIPLE_OUTPUTS = "mapreduce.multipleoutputs";
+
+  private static final String MO_PREFIX = 
+    "mapreduce.multipleoutputs.namedOutput.";
+
+  private static final String FORMAT = ".format";
+  private static final String KEY = ".key";
+  private static final String VALUE = ".value";
+  private static final String COUNTERS_ENABLED = 
+    "mapreduce.multipleoutputs.counters";
+
+  private static final String BASE_OUTPUT_NAME = "mapreduce.output.basename";
+  
+  /**
+   * Counters group used by the counters of MultipleOutputs.
+   */
+  private static final String COUNTERS_GROUP = CrunchMultipleOutputs.class.getName();
+  
+  /**
+   * Cache for the taskContexts
+   */
+  private Map<String, TaskAttemptContext> taskContexts = new HashMap<String, TaskAttemptContext>();
+
+  /**
+   * Checks if a named output name is valid token.
+   *
+   * @param namedOutput named output Name
+   * @throws IllegalArgumentException if the output name is not valid.
+   */
+  private static void checkTokenName(String namedOutput) {
+    if (namedOutput == null || namedOutput.length() == 0) {
+      throw new IllegalArgumentException(
+        "Name cannot be NULL or emtpy");
+    }
+    for (char ch : namedOutput.toCharArray()) {
+      if ((ch >= 'A') && (ch <= 'Z')) {
+        continue;
+      }
+      if ((ch >= 'a') && (ch <= 'z')) {
+        continue;
+      }
+      if ((ch >= '0') && (ch <= '9')) {
+        continue;
+      }
+      throw new IllegalArgumentException(
+        "Name cannot be have a '" + ch + "' char");
+    }
+  }
+
+  /**
+   * Checks if output name is valid.
+   *
+   * name cannot be the name used for the default output
+   * @param outputPath base output Name
+   * @throws IllegalArgumentException if the output name is not valid.
+   */
+  private static void checkBaseOutputPath(String outputPath) {
+    if (outputPath.equals(FileOutputFormat.PART)) {
+      throw new IllegalArgumentException("output name cannot be 'part'");
+    }
+  }
+  
+  /**
+   * Checks if a named output name is valid.
+   *
+   * @param namedOutput named output Name
+   * @throws IllegalArgumentException if the output name is not valid.
+   */
+  private static void checkNamedOutputName(JobContext job,
+      String namedOutput, boolean alreadyDefined) {
+    checkTokenName(namedOutput);
+    checkBaseOutputPath(namedOutput);
+    List<String> definedChannels = getNamedOutputsList(job);
+    if (alreadyDefined && definedChannels.contains(namedOutput)) {
+      throw new IllegalArgumentException("Named output '" + namedOutput +
+        "' already alreadyDefined");
+    } else if (!alreadyDefined && !definedChannels.contains(namedOutput)) {
+      throw new IllegalArgumentException("Named output '" + namedOutput +
+        "' not defined");
+    }
+  }
+
+  // Returns list of channel names.
+  private static List<String> getNamedOutputsList(JobContext job) {
+    List<String> names = new ArrayList<String>();
+    StringTokenizer st = new StringTokenizer(
+      job.getConfiguration().get(MULTIPLE_OUTPUTS, ""), " ");
+    while (st.hasMoreTokens()) {
+      names.add(st.nextToken());
+    }
+    return names;
+  }
+
+  // Returns the named output OutputFormat.
+  @SuppressWarnings("unchecked")
+  private static Class<? extends OutputFormat<?, ?>> getNamedOutputFormatClass(
+    JobContext job, String namedOutput) {
+    return (Class<? extends OutputFormat<?, ?>>)
+      job.getConfiguration().getClass(MO_PREFIX + namedOutput + FORMAT, null,
+      OutputFormat.class);
+  }
+
+  // Returns the key class for a named output.
+  private static Class<?> getNamedOutputKeyClass(JobContext job,
+                                                String namedOutput) {
+    return job.getConfiguration().getClass(MO_PREFIX + namedOutput + KEY, null,
+      Object.class);
+  }
+
+  // Returns the value class for a named output.
+  private static Class<?> getNamedOutputValueClass(
+      JobContext job, String namedOutput) {
+    return job.getConfiguration().getClass(MO_PREFIX + namedOutput + VALUE,
+      null, Object.class);
+  }
+
+  /**
+   * Adds a named output for the job.
+   * <p/>
+   *
+   * @param job               job to add the named output
+   * @param namedOutput       named output name, it has to be a word, letters
+   *                          and numbers only, cannot be the word 'part' as
+   *                          that is reserved for the default output.
+   * @param outputFormatClass OutputFormat class.
+   * @param keyClass          key class
+   * @param valueClass        value class
+   */
+  public static void addNamedOutput(Job job, String namedOutput,
+      Class<? extends OutputFormat> outputFormatClass,
+      Class<?> keyClass, Class<?> valueClass) {
+    checkNamedOutputName(job, namedOutput, true);
+    Configuration conf = job.getConfiguration();
+    conf.set(MULTIPLE_OUTPUTS,
+      conf.get(MULTIPLE_OUTPUTS, "") + " " + namedOutput);
+    conf.setClass(MO_PREFIX + namedOutput + FORMAT, outputFormatClass,
+      OutputFormat.class);
+    conf.setClass(MO_PREFIX + namedOutput + KEY, keyClass, Object.class);
+    conf.setClass(MO_PREFIX + namedOutput + VALUE, valueClass, Object.class);
+  }
+
+  /**
+   * Enables or disables counters for the named outputs.
+   * 
+   * The counters group is the {@link CrunchMultipleOutputs} class name.
+   * The names of the counters are the same as the named outputs. These
+   * counters count the number records written to each output name.
+   * By default these counters are disabled.
+   *
+   * @param job    job  to enable counters
+   * @param enabled indicates if the counters will be enabled or not.
+   */
+  public static void setCountersEnabled(Job job, boolean enabled) {
+    job.getConfiguration().setBoolean(COUNTERS_ENABLED, enabled);
+  }
+
+  /**
+   * Returns if the counters for the named outputs are enabled or not.
+   * By default these counters are disabled.
+   *
+   * @param job    the job 
+   * @return TRUE if the counters are enabled, FALSE if they are disabled.
+   */
+  public static boolean getCountersEnabled(JobContext job) {
+    return job.getConfiguration().getBoolean(COUNTERS_ENABLED, false);
+  }
+
+  /**
+   * Wraps RecordWriter to increment counters. 
+   */
+  @SuppressWarnings("unchecked")
+  private static class RecordWriterWithCounter extends RecordWriter {
+    private RecordWriter writer;
+    private String counterName;
+    private TaskInputOutputContext context;
+
+    public RecordWriterWithCounter(RecordWriter writer, String counterName,
+                                   TaskInputOutputContext context) {
+      this.writer = writer;
+      this.counterName = counterName;
+      this.context = context;
+    }
+
+    @SuppressWarnings({"unchecked"})
+    public void write(Object key, Object value) 
+        throws IOException, InterruptedException {
+      context.getCounter(COUNTERS_GROUP, counterName).increment(1);
+      writer.write(key, value);
+    }
+
+    public void close(TaskAttemptContext context) 
+        throws IOException, InterruptedException {
+      writer.close(context);
+    }
+  }
+
+  // instance code, to be used from Mapper/Reducer code
+
+  private TaskInputOutputContext<?, ?, KEYOUT, VALUEOUT> context;
+  private Set<String> namedOutputs;
+  private Map<String, RecordWriter<?, ?>> recordWriters;
+  private boolean countersEnabled;
+  
+  /**
+   * Creates and initializes multiple outputs support,
+   * it should be instantiated in the Mapper/Reducer setup method.
+   *
+   * @param context the TaskInputOutputContext object
+   */
+  public CrunchMultipleOutputs(
+      TaskInputOutputContext<?, ?, KEYOUT, VALUEOUT> context) {
+    this.context = context;
+    namedOutputs = Collections.unmodifiableSet(
+      new HashSet<String>(CrunchMultipleOutputs.getNamedOutputsList(context)));
+    recordWriters = new HashMap<String, RecordWriter<?, ?>>();
+    countersEnabled = getCountersEnabled(context);
+  }
+
+  /**
+   * Write key and value to the namedOutput.
+   *
+   * Output path is a unique file generated for the namedOutput.
+   * For example, {namedOutput}-(m|r)-{part-number}
+   * 
+   * @param namedOutput the named output name
+   * @param key         the key
+   * @param value       the value
+   */
+  @SuppressWarnings("unchecked")
+  public <K, V> void write(String namedOutput, K key, V value)
+      throws IOException, InterruptedException {
+    write(namedOutput, key, value, namedOutput);
+  }
+
+  /**
+   * Write key and value to baseOutputPath using the namedOutput.
+   * 
+   * @param namedOutput    the named output name
+   * @param key            the key
+   * @param value          the value
+   * @param baseOutputPath base-output path to write the record to.
+   * Note: Framework will generate unique filename for the baseOutputPath
+   */
+  @SuppressWarnings("unchecked")
+  public <K, V> void write(String namedOutput, K key, V value,
+      String baseOutputPath) throws IOException, InterruptedException {
+    checkNamedOutputName(context, namedOutput, false);
+    checkBaseOutputPath(baseOutputPath);
+    if (!namedOutputs.contains(namedOutput)) {
+      throw new IllegalArgumentException("Undefined named output '" +
+        namedOutput + "'");
+    }
+    TaskAttemptContext taskContext = getContext(namedOutput);
+    getRecordWriter(taskContext, baseOutputPath).write(key, value);
+  }
+
+  /**
+   * Write key value to an output file name.
+   * 
+   * Gets the record writer from job's output format.  
+   * Job's output format should be a FileOutputFormat.
+   * 
+   * @param key       the key
+   * @param value     the value
+   * @param baseOutputPath base-output path to write the record to.
+   * Note: Framework will generate unique filename for the baseOutputPath
+   */
+  @SuppressWarnings("unchecked")
+  public void write(KEYOUT key, VALUEOUT value, String baseOutputPath) 
+      throws IOException, InterruptedException {
+    checkBaseOutputPath(baseOutputPath);
+    TaskAttemptContext taskContext = TaskAttemptContextFactory.create(
+      context.getConfiguration(), context.getTaskAttemptID());
+    getRecordWriter(taskContext, baseOutputPath).write(key, value);
+  }
+
+  // by being synchronized MultipleOutputTask can be use with a
+  // MultithreadedMapper.
+  @SuppressWarnings("unchecked")
+  private synchronized RecordWriter getRecordWriter(
+      TaskAttemptContext taskContext, String baseFileName) 
+      throws IOException, InterruptedException {
+    
+    // look for record-writer in the cache
+    RecordWriter writer = recordWriters.get(baseFileName);
+    
+    // If not in cache, create a new one
+    if (writer == null) {
+      // get the record writer from context output format
+      taskContext.getConfiguration().set(BASE_OUTPUT_NAME, baseFileName);
+      try {
+        writer = ((OutputFormat) ReflectionUtils.newInstance(
+          taskContext.getOutputFormatClass(), taskContext.getConfiguration()))
+          .getRecordWriter(taskContext);
+      } catch (ClassNotFoundException e) {
+        throw new IOException(e);
+      }
+ 
+      // if counters are enabled, wrap the writer with context 
+      // to increment counters 
+      if (countersEnabled) {
+        writer = new RecordWriterWithCounter(writer, baseFileName, context);
+      }
+      
+      // add the record-writer to the cache
+      recordWriters.put(baseFileName, writer);
+    }
+    return writer;
+  }
+
+   // Create a taskAttemptContext for the named output with 
+   // output format and output key/value types put in the context
+  private TaskAttemptContext getContext(String nameOutput) throws IOException {
+
+    TaskAttemptContext taskContext = taskContexts.get(nameOutput);
+
+    if (taskContext != null) {
+      return taskContext;
+    }
+
+    // The following trick leverages the instantiation of a record writer via
+    // the job thus supporting arbitrary output formats.
+    Job job = new Job(context.getConfiguration());
+    job.getConfiguration().set("crunch.namedoutput", nameOutput);
+    job.setOutputFormatClass(getNamedOutputFormatClass(context, nameOutput));
+    job.setOutputKeyClass(getNamedOutputKeyClass(context, nameOutput));
+    job.setOutputValueClass(getNamedOutputValueClass(context, nameOutput));
+    taskContext = TaskAttemptContextFactory.create(
+      job.getConfiguration(), context.getTaskAttemptID());
+    
+    taskContexts.put(nameOutput, taskContext);
+    
+    return taskContext;
+  }
+  
+  /**
+   * Closes all the opened outputs.
+   * 
+   * This should be called from cleanup method of map/reduce task.
+   * If overridden subclasses must invoke <code>super.close()</code> at the
+   * end of their <code>close()</code>
+   * 
+   */
+  @SuppressWarnings("unchecked")
+  public void close() throws IOException, InterruptedException {
+    for (RecordWriter writer : recordWriters.values()) {
+      writer.close(context);
+    }
+  }
+}