Author: alexparvulescu
Date: Fri Dec  2 10:58:41 2011
New Revision: 1209402

URL: http://svn.apache.org/viewvc?rev=1209402&view=rev
Log:
JCR-3165 Consolidate compare behaviour for Value(s) and Comparable(s)

Modified:
    jackrabbit/trunk/jackrabbit-core/src/main/java/org/apache/jackrabbit/core/query/lucene/Util.java
    jackrabbit/trunk/jackrabbit-core/src/main/java/org/apache/jackrabbit/core/query/lucene/join/ValueComparator.java
    jackrabbit/trunk/jackrabbit-core/src/main/java/org/apache/jackrabbit/core/query/lucene/sort/RowComparator.java
    jackrabbit/trunk/jackrabbit-core/src/main/java/org/apache/jackrabbit/core/query/lucene/sort/ValueComparableWrapper.java

Modified: jackrabbit/trunk/jackrabbit-core/src/main/java/org/apache/jackrabbit/core/query/lucene/Util.java
URL: http://svn.apache.org/viewvc/jackrabbit/trunk/jackrabbit-core/src/main/java/org/apache/jackrabbit/core/query/lucene/Util.java?rev=1209402&r1=1209401&r2=1209402&view=diff
==============================================================================
--- jackrabbit/trunk/jackrabbit-core/src/main/java/org/apache/jackrabbit/core/query/lucene/Util.java (original)
+++ jackrabbit/trunk/jackrabbit-core/src/main/java/org/apache/jackrabbit/core/query/lucene/Util.java Fri Dec  2 10:58:41 2011
@@ -16,24 +16,24 @@
  */
 package org.apache.jackrabbit.core.query.lucene;
 
-import org.apache.lucene.document.Document;
-import org.apache.lucene.document.Fieldable;
-import org.apache.lucene.search.Query;
-import org.apache.lucene.index.Term;
-import org.apache.lucene.index.IndexReader;
-import org.apache.jackrabbit.core.value.InternalValue;
-import org.slf4j.LoggerFactory;
-import org.slf4j.Logger;
-
-import java.util.regex.Pattern;
 import java.io.IOException;
 import java.io.UnsupportedEncodingException;
 import java.net.URLDecoder;
+import java.util.regex.Pattern;
 
 import javax.jcr.PropertyType;
+import javax.jcr.RepositoryException;
 import javax.jcr.Value;
 import javax.jcr.ValueFormatException;
-import javax.jcr.RepositoryException;
+
+import org.apache.jackrabbit.core.value.InternalValue;
+import org.apache.lucene.document.Document;
+import org.apache.lucene.document.Fieldable;
+import org.apache.lucene.index.IndexReader;
+import org.apache.lucene.index.Term;
+import org.apache.lucene.search.Query;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 
 /**
  * <code>Util</code> provides various static utility methods.
@@ -48,8 +48,9 @@ public class Util {
     /**
      * Disposes the document <code>old</code>. Closes any potentially open
      * readers held by the document.
-     *
-     * @param old the document to dispose.
+     * 
+     * @param old
+     *            the document to dispose.
      */
     public static void disposeDocument(Document old) {
         for (Fieldable f : old.getFields()) {
@@ -69,8 +70,9 @@ public class Util {
     /**
      * Returns <code>true</code> if the document is ready to be added to the
      * index. That is all text extractors have finished their work.
-     *
-     * @param doc the document to check.
+     * 
+     * @param doc
+     *            the document to check.
      * @return <code>true</code> if the document is ready; <code>false</code>
      *         otherwise.
      */
@@ -89,17 +91,20 @@ public class Util {
     /**
      * Depending on the index format this method returns a query that matches
      * all nodes that have a property with a given <code>name</code>.
-     *
-     * @param name    the property name.
-     * @param version the index format version.
+     * 
+     * @param name
+     *            the property name.
+     * @param version
+     *            the index format version.
      * @return Query that matches all nodes that have a property with the given
      *         <code>name</code>.
      */
-    public static Query createMatchAllQuery(
-            String name, IndexFormatVersion version, PerQueryCache cache) {
+    public static Query createMatchAllQuery(String name,
+            IndexFormatVersion version, PerQueryCache cache) {
         if (version.getVersion() >= IndexFormatVersion.V2.getVersion()) {
             // new index format style
-            return new JackrabbitTermQuery(new Term(FieldNames.PROPERTIES_SET, name));
+            return new JackrabbitTermQuery(new Term(FieldNames.PROPERTIES_SET,
+                    name));
         } else {
             return new MatchAllQuery(name, cache);
         }
@@ -107,8 +112,9 @@ public class Util {
 
     /**
      * Creates an {@link IOException} with <code>t</code> as its cause.
-     *
-     * @param t the cause.
+     * 
+     * @param t
+     *            the cause.
      */
     public static IOException createIOException(Throwable t) {
         IOException ex = new IOException(t.getMessage());
@@ -120,10 +126,12 @@ public class Util {
      * Depending on the type of the <code>reader</code> this method either
      * closes or releases the reader. The reader is released if it implements
      * {@link ReleaseableIndexReader}.
-     *
-     * @param reader the index reader to close or release.
-     * @throws IOException if an error occurs while closing or releasing the
-     *                     index reader.
+     * 
+     * @param reader
+     *            the index reader to close or release.
+     * @throws IOException
+     *             if an error occurs while closing or releasing the index
+     *             reader.
      */
     public static void closeOrRelease(IndexReader reader) throws IOException {
         if (reader instanceof ReleaseableIndexReader) {
@@ -135,88 +143,94 @@ public class Util {
 
     /**
      * Returns a comparable for the internal <code>value</code>.
-     *
-     * @param value an internal value.
+     * 
+     * @param value
+     *            an internal value.
      * @return a comparable for the given <code>value</code>.
-     * @throws RepositoryException if retrieving the <code>Comparable</code> fails.
+     * @throws RepositoryException
+     *             if retrieving the <code>Comparable</code> fails.
      */
-    public static Comparable getComparable(InternalValue value) throws RepositoryException {
+    public static Comparable getComparable(InternalValue value)
+            throws RepositoryException {
         switch (value.getType()) {
-            case PropertyType.BINARY:
-                return null;
-            case PropertyType.BOOLEAN:
-                return value.getBoolean();
-            case PropertyType.DATE:
-                return value.getDate().getTimeInMillis();
-            case PropertyType.DOUBLE:
-                return value.getDouble();
-            case PropertyType.LONG:
-                return value.getLong();
-            case PropertyType.DECIMAL:
-                return value.getDecimal();
-            case PropertyType.NAME:
-                return value.getName().toString();
-            case PropertyType.PATH:
-                return value.getPath().toString();
-            case PropertyType.URI:
-            case PropertyType.WEAKREFERENCE:
-            case PropertyType.REFERENCE:
-            case PropertyType.STRING:
-                return value.getString();
-            default:
-                return null;
+        case PropertyType.BINARY:
+            return null;
+        case PropertyType.BOOLEAN:
+            return value.getBoolean();
+        case PropertyType.DATE:
+            return value.getDate().getTimeInMillis();
+        case PropertyType.DOUBLE:
+            return value.getDouble();
+        case PropertyType.LONG:
+            return value.getLong();
+        case PropertyType.DECIMAL:
+            return value.getDecimal();
+        case PropertyType.NAME:
+            return value.getName().toString();
+        case PropertyType.PATH:
+            return value.getPath().toString();
+        case PropertyType.URI:
+        case PropertyType.WEAKREFERENCE:
+        case PropertyType.REFERENCE:
+        case PropertyType.STRING:
+            return value.getString();
+        default:
+            return null;
         }
     }
 
     /**
      * Returns a comparable for the internal <code>value</code>.
-     *
-     * @param value an internal value.
+     * 
+     * @param value
+     *            an internal value.
      * @return a comparable for the given <code>value</code>.
-     * @throws ValueFormatException if the given <code>value</code> cannot be
-     *                              converted into a comparable (i.e.
-     *                              unsupported type).
-     * @throws RepositoryException  if an error occurs while converting the
-     *                              value.
+     * @throws ValueFormatException
+     *             if the given <code>value</code> cannot be converted into a
+     *             comparable (i.e. unsupported type).
+     * @throws RepositoryException
+     *             if an error occurs while converting the value.
      */
     public static Comparable getComparable(Value value)
             throws ValueFormatException, RepositoryException {
         switch (value.getType()) {
-            case PropertyType.BOOLEAN:
-                return value.getBoolean();
-            case PropertyType.DATE:
-                return value.getDate().getTimeInMillis();
-            case PropertyType.DOUBLE:
-                return value.getDouble();
-            case PropertyType.LONG:
-                return value.getLong();
-            case PropertyType.DECIMAL:
-                return value.getDecimal();
-            case PropertyType.NAME:
-            case PropertyType.PATH:
-            case PropertyType.URI:
-            case PropertyType.WEAKREFERENCE:
-            case PropertyType.REFERENCE:
-            case PropertyType.STRING:
-                return value.getString();
-            default:
-                throw new RepositoryException("Unsupported type: "
-                        + PropertyType.nameFromValue(value.getType()));
+        case PropertyType.BOOLEAN:
+            return value.getBoolean();
+        case PropertyType.DATE:
+            return value.getDate().getTimeInMillis();
+        case PropertyType.DOUBLE:
+            return value.getDouble();
+        case PropertyType.LONG:
+            return value.getLong();
+        case PropertyType.DECIMAL:
+            return value.getDecimal();
+        case PropertyType.NAME:
+        case PropertyType.PATH:
+        case PropertyType.URI:
+        case PropertyType.WEAKREFERENCE:
+        case PropertyType.REFERENCE:
+        case PropertyType.STRING:
+            return value.getString();
+        default:
+            throw new RepositoryException("Unsupported type: "
+                    + PropertyType.nameFromValue(value.getType()));
         }
     }
 
     /**
-     * Compares values <code>c1</code> and <code>c2</code>. If the
-     * values have differing types, then the order is defined on
-     * the type itself by calling <code>compareTo()</code> on the respective
-     * type class names.
-     *
-     * @param c1 the first value.
-     * @param c2 the second value.
+     * Compares values <code>c1</code> and <code>c2</code>. If the values have
+     * differing types, then the order is defined on the type itself by calling
+     * <code>compareTo()</code> on the respective type class names.
+     * 
+     * @param c1
+     *            the first value.
+     * @param c2
+     *            the second value.
      * @return a negative integer if <code>c1</code> should come before
-     *         <code>c2</code><br> a positive integer if <code>c1</code>
-     *         should come after <code>c2</code><br> <code>0</code> if they
-     *         are equal.
+     *         <code>c2</code><br>
+     *         a positive integer if <code>c1</code> should come after
+     *         <code>c2</code><br>
+     *         <code>0</code> if they are equal.
      */
     public static int compare(Comparable c1, Comparable c2) {
         if (c1 == c2) {
@@ -236,7 +250,11 @@ public class Util {
     }
 
     /**
-     * Compares two arrays of comparables.
+     * Compares two arrays of Comparable(s) in the same style as
+     * {@link #compare(Value[], Value[])}.
+     * 
+     * The 2 methods *have* to work in the same way for the sort to be
+     * consistent
      */
     public static int compare(Comparable<?>[] c1, Comparable<?>[] c2) {
         if (c1 == null) {
@@ -255,76 +273,102 @@ public class Util {
     }
 
     /**
+     * Compares two arrays of Value(s) in the same style as
+     * {@link #compare(Comparable[], Comparable[])}.
+     * 
+     * The 2 methods *have* to work in the same way for the sort to be
+     * consistent
+     */
+    public static int compare(Value[] a, Value[] b) throws RepositoryException {
+        if (a == null) {
+            return -1;
+        }
+        if (b == null) {
+            return 1;
+        }
+        for (int i = 0; i < a.length && i < b.length; i++) {
+            int d = compare(a[i], b[i]);
+            if (d != 0) {
+                return d;
+            }
+        }
+        return a.length - b.length;
+    }
+
+    /**
      * Compares the two values. If the values have differing types, then an
      * attempt is made to convert the second value into the type of the first
      * value.
      * <p/>
      * Comparison of binary values is not supported.
-     *
-     * @param v1 the first value.
-     * @param v2 the second value.
+     * 
+     * @param v1
+     *            the first value.
+     * @param v2
+     *            the second value.
      * @return result of the comparison as specified in
      *         {@link Comparable#compareTo(Object)}.
-     * @throws ValueFormatException if the given <code>value</code> cannot be
-     *                              converted into a comparable (i.e.
-     *                              unsupported type).
-     * @throws RepositoryException  if an error occurs while converting the
-     *                              value.
+     * @throws ValueFormatException
+     *             if the given <code>value</code> cannot be converted into a
+     *             comparable (i.e. unsupported type).
+     * @throws RepositoryException
+     *             if an error occurs while converting the value.
      */
-    public static int compare(Value v1, Value v2)
-            throws ValueFormatException, RepositoryException {
+    public static int compare(Value v1, Value v2) throws ValueFormatException,
+            RepositoryException {
         Comparable c1 = getComparable(v1);
         Comparable c2;
         switch (v1.getType()) {
-            case PropertyType.BOOLEAN:
-                c2 = v2.getBoolean();
-                break;
-            case PropertyType.DATE:
-                c2 = v2.getDate().getTimeInMillis();
-                break;
-            case PropertyType.DOUBLE:
-                c2 = v2.getDouble();
-                break;
-            case PropertyType.LONG:
-                c2 = v2.getLong();
-                break;
-            case PropertyType.DECIMAL:
-                c2 = v2.getDecimal();
-                break;
-            case PropertyType.NAME:
-                if (v2.getType() == PropertyType.URI) {
-                    String s = v2.getString();
-                    if (s.startsWith("./")) {
-                        s = s.substring(2);
-                    }
-                    // need to decode
-                    try {
-                        c2 = URLDecoder.decode(s, "UTF-8");
-                    } catch (UnsupportedEncodingException e) {
-                        throw new RepositoryException(e);
-                    }
-                } else {
-                    c2 = v2.getString();
+        case PropertyType.BOOLEAN:
+            c2 = v2.getBoolean();
+            break;
+        case PropertyType.DATE:
+            c2 = v2.getDate().getTimeInMillis();
+            break;
+        case PropertyType.DOUBLE:
+            c2 = v2.getDouble();
+            break;
+        case PropertyType.LONG:
+            c2 = v2.getLong();
+            break;
+        case PropertyType.DECIMAL:
+            c2 = v2.getDecimal();
+            break;
+        case PropertyType.NAME:
+            if (v2.getType() == PropertyType.URI) {
+                String s = v2.getString();
+                if (s.startsWith("./")) {
+                    s = s.substring(2);
+                }
+                // need to decode
+                try {
+                    c2 = URLDecoder.decode(s, "UTF-8");
+                } catch (UnsupportedEncodingException e) {
+                    throw new RepositoryException(e);
                 }
-                break;
-            case PropertyType.PATH:
-            case PropertyType.REFERENCE:
-            case PropertyType.WEAKREFERENCE:
-            case PropertyType.URI:
-            case PropertyType.STRING:
+            } else {
                 c2 = v2.getString();
-                break;
-            default:
-                throw new RepositoryException("Unsupported type: "
-                        + PropertyType.nameFromValue(v2.getType()));
+            }
+            break;
+        case PropertyType.PATH:
+        case PropertyType.REFERENCE:
+        case PropertyType.WEAKREFERENCE:
+        case PropertyType.URI:
+        case PropertyType.STRING:
+            c2 = v2.getString();
+            break;
+        default:
+            throw new RepositoryException("Unsupported type: "
+                    + PropertyType.nameFromValue(v2.getType()));
         }
         return compare(c1, c2);
     }
 
     /**
      * Creates a regexp from <code>likePattern</code>.
-     *
-     * @param likePattern the pattern.
+     * 
+     * @param likePattern
+     *            the pattern.
      * @return the regular expression <code>Pattern</code>.
      */
     public static Pattern createRegexp(String likePattern) {
@@ -355,14 +399,14 @@ public class Util {
                         escaped = false;
                     } else {
                         switch (likePattern.charAt(i)) {
-                            case '_':
-                                regexp.append('.');
-                                break;
-                            case '%':
-                                regexp.append(".*");
-                                break;
-                            default:
-                                regexp.append('\\').append(likePattern.charAt(i));
+                        case '_':
+                            regexp.append('.');
+                            break;
+                        case '%':
+                            regexp.append(".*");
+                            break;
+                        default:
+                            regexp.append('\\').append(likePattern.charAt(i));
                         }
                     }
                 }
@@ -373,8 +417,9 @@ public class Util {
 
     /**
      * Returns length of the internal value.
-     *
-     * @param value a value.
+     * 
+     * @param value
+     *            a value.
      * @return the length of the internal value or <code>-1</code> if the length
      *         cannot be determined.
      */

Modified: jackrabbit/trunk/jackrabbit-core/src/main/java/org/apache/jackrabbit/core/query/lucene/join/ValueComparator.java
URL: http://svn.apache.org/viewvc/jackrabbit/trunk/jackrabbit-core/src/main/java/org/apache/jackrabbit/core/query/lucene/join/ValueComparator.java?rev=1209402&r1=1209401&r2=1209402&view=diff
==============================================================================
--- jackrabbit/trunk/jackrabbit-core/src/main/java/org/apache/jackrabbit/core/query/lucene/join/ValueComparator.java (original)
+++ jackrabbit/trunk/jackrabbit-core/src/main/java/org/apache/jackrabbit/core/query/lucene/join/ValueComparator.java Fri Dec  2 10:58:41 2011
@@ -16,10 +16,6 @@
  */
 package org.apache.jackrabbit.core.query.lucene.join;
 
-import static javax.jcr.PropertyType.DATE;
-import static javax.jcr.PropertyType.DECIMAL;
-import static javax.jcr.PropertyType.DOUBLE;
-import static javax.jcr.PropertyType.LONG;
 import static javax.jcr.query.qom.QueryObjectModelConstants.JCR_OPERATOR_EQUAL_TO;
 import static javax.jcr.query.qom.QueryObjectModelConstants.JCR_OPERATOR_GREATER_THAN;
 import static javax.jcr.query.qom.QueryObjectModelConstants.JCR_OPERATOR_GREATER_THAN_OR_EQUAL_TO;
@@ -28,6 +24,7 @@ import static javax.jcr.query.qom.QueryO
 import static javax.jcr.query.qom.QueryObjectModelConstants.JCR_OPERATOR_LIKE;
 import static javax.jcr.query.qom.QueryObjectModelConstants.JCR_OPERATOR_NOT_EQUAL_TO;
 
+import java.util.Arrays;
 import java.util.Comparator;
 import java.util.regex.Pattern;
 
@@ -46,20 +43,10 @@ public class ValueComparator implements 
      */
     public int compare(Value a, Value b) {
         try {
-            int ta = a.getType();
-            int tb = b.getType();
-
-            if ((ta == DECIMAL || ta == DOUBLE || ta == LONG)
-                    && (tb == DECIMAL || tb == DOUBLE || tb == LONG)) {
-                return a.getDecimal().compareTo(b.getDecimal());
-            } else if (ta == DATE && tb == DATE) {
-                return a.getDate().compareTo(b.getDate());
-            } else {
-                return a.getString().compareTo(b.getString());
-            }
+            return Util.compare(a, b);
         } catch (RepositoryException e) {
-            throw new RuntimeException(
-                    "Unable to compare values " + a + " and " + b, e);
+            throw new RuntimeException("Unable to compare values " + a
+                    + " and " + b, e);
         }
     }
 
@@ -98,6 +85,15 @@ public class ValueComparator implements 
         }
     }
 
+    public int compare(Value[] a, Value[] b) {
+        try {
+            return Util.compare(a, b);
+        } catch (RepositoryException e) {
+            throw new RuntimeException("Unable to compare values "
+                    + Arrays.toString(a) + " and " + Arrays.toString(b), e);
+        }
+    }
+
     /**
      * Evaluates the given QOM comparison operation with the given value arrays.
      *
@@ -108,15 +104,20 @@ public class ValueComparator implements 
      */
     public boolean evaluate(String operator, Value[] a, Value[] b) {
         if (JCR_OPERATOR_EQUAL_TO.equals(operator)) {
-            for (int i = 0; i < a.length; i++) {
-                for (int j = 0; j < b.length; j++) {
-                    if (compare(a[i], b[j]) == 0) {
-                        return true;
-                    }
-                }
-            }
+            return compare(a, b) == 0;
+        } else if (JCR_OPERATOR_GREATER_THAN.equals(operator)) {
+            return compare(a, b) > 0;
+        } else if (JCR_OPERATOR_GREATER_THAN_OR_EQUAL_TO.equals(operator)) {
+            return compare(a, b) >= 0;
+        } else if (JCR_OPERATOR_LESS_THAN.equals(operator)) {
+            return compare(a, b) < 0;
+        } else if (JCR_OPERATOR_LESS_THAN_OR_EQUAL_TO.equals(operator)) {
+            return compare(a, b) <= 0;
+        } else if (JCR_OPERATOR_NOT_EQUAL_TO.equals(operator)) {
+            return compare(a, b) != 0;
         }
-        return false; // FIXME
+        // TODO JCR_OPERATOR_LIKE
+        throw new IllegalArgumentException("Unknown comparison operator: "
+                + operator);
     }
-
-}
\ No newline at end of file
+}

Modified: jackrabbit/trunk/jackrabbit-core/src/main/java/org/apache/jackrabbit/core/query/lucene/sort/RowComparator.java
URL: http://svn.apache.org/viewvc/jackrabbit/trunk/jackrabbit-core/src/main/java/org/apache/jackrabbit/core/query/lucene/sort/RowComparator.java?rev=1209402&r1=1209401&r2=1209402&view=diff
==============================================================================
--- jackrabbit/trunk/jackrabbit-core/src/main/java/org/apache/jackrabbit/core/query/lucene/sort/RowComparator.java (original)
+++ jackrabbit/trunk/jackrabbit-core/src/main/java/org/apache/jackrabbit/core/query/lucene/sort/RowComparator.java Fri Dec  2 10:58:41 2011
@@ -34,7 +34,7 @@ import org.apache.jackrabbit.core.query.
  */
 public class RowComparator implements Comparator<Row> {
 
-    private final ValueComparator comparator = new ValueComparator();
+    private static final ValueComparator comparator = new ValueComparator();
 
     private final Ordering[] orderings;
 
@@ -51,7 +51,7 @@ public class RowComparator implements Co
                 Operand operand = ordering.getOperand();
                 Value[] va = evaluator.getValues(operand, a);
                 Value[] vb = evaluator.getValues(operand, b);
-                int d = compare(va, vb);
+                int d = comparator.compare(va, vb);
                 if (d != 0) {
                     if (JCR_ORDER_DESCENDING.equals(ordering.getOrder())) {
                         return -d;
@@ -66,15 +66,4 @@ public class RowComparator implements Co
                     + b, e);
         }
     }
-
-    private int compare(Value[] a, Value[] b) {
-        for (int i = 0; i < a.length && i < b.length; i++) {
-            int d = comparator.compare(a[i], b[i]);
-            if (d != 0) {
-                return d;
-            }
-        }
-        return a.length - b.length;
-    }
-
-}
\ No newline at end of file
+}

Modified: jackrabbit/trunk/jackrabbit-core/src/main/java/org/apache/jackrabbit/core/query/lucene/sort/ValueComparableWrapper.java
URL: http://svn.apache.org/viewvc/jackrabbit/trunk/jackrabbit-core/src/main/java/org/apache/jackrabbit/core/query/lucene/sort/ValueComparableWrapper.java?rev=1209402&r1=1209401&r2=1209402&view=diff
==============================================================================
--- jackrabbit/trunk/jackrabbit-core/src/main/java/org/apache/jackrabbit/core/query/lucene/sort/ValueComparableWrapper.java (original)
+++ jackrabbit/trunk/jackrabbit-core/src/main/java/org/apache/jackrabbit/core/query/lucene/sort/ValueComparableWrapper.java Fri Dec  2 10:58:41 2011
@@ -21,7 +21,8 @@ import javax.jcr.Value;
 import org.apache.jackrabbit.core.query.lucene.join.ValueComparator;
 
 class ValueComparableWrapper implements Comparable<ValueComparableWrapper> {
-    private final static ValueComparator comparator = new ValueComparator();
+
+    private static final ValueComparator comparator = new ValueComparator();
 
     private final Value[] v;
 
@@ -30,16 +31,6 @@ class ValueComparableWrapper implements 
     }
 
     public int compareTo(ValueComparableWrapper o) {
-        return compare(v, o.v);
-    }
-
-    private int compare(Value[] a, Value[] b) {
-        for (int i = 0; i < a.length && i < b.length; i++) {
-            int d = comparator.compare(a[i], b[i]);
-            if (d != 0) {
-                return d;
-            }
-        }
-        return a.length - b.length;
+        return comparator.compare(v, o.v);
     }
 }