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From doeb...@apache.org
Subject empire-db git commit: EMPIREDB-238 added column expression for scalar functions
Date Mon, 07 Mar 2016 17:54:18 GMT
Repository: empire-db
Updated Branches:
  refs/heads/master ffe2eb52a -> 59db7a5b0


EMPIREDB-238
added column expression for scalar functions

Project: http://git-wip-us.apache.org/repos/asf/empire-db/repo
Commit: http://git-wip-us.apache.org/repos/asf/empire-db/commit/59db7a5b
Tree: http://git-wip-us.apache.org/repos/asf/empire-db/tree/59db7a5b
Diff: http://git-wip-us.apache.org/repos/asf/empire-db/diff/59db7a5b

Branch: refs/heads/master
Commit: 59db7a5b08abfc1494149cd30d0e8dc14b4ce16f
Parents: ffe2eb5
Author: Rainer Döbele <doebele@apache.org>
Authored: Mon Mar 7 18:54:12 2016 +0100
Committer: Rainer Döbele <doebele@apache.org>
Committed: Mon Mar 7 18:54:12 2016 +0100

----------------------------------------------------------------------
 .../empire/db/expr/column/DBScalarExpr.java     | 199 +++++++++++++++++++
 1 file changed, 199 insertions(+)
----------------------------------------------------------------------


http://git-wip-us.apache.org/repos/asf/empire-db/blob/59db7a5b/empire-db/src/main/java/org/apache/empire/db/expr/column/DBScalarExpr.java
----------------------------------------------------------------------
diff --git a/empire-db/src/main/java/org/apache/empire/db/expr/column/DBScalarExpr.java b/empire-db/src/main/java/org/apache/empire/db/expr/column/DBScalarExpr.java
new file mode 100644
index 0000000..574aab4
--- /dev/null
+++ b/empire-db/src/main/java/org/apache/empire/db/expr/column/DBScalarExpr.java
@@ -0,0 +1,199 @@
+/*
+ * 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.empire.db.expr.column;
+
+// Java
+import java.util.Set;
+
+import org.apache.empire.commons.StringUtils;
+import org.apache.empire.data.DataType;
+import org.apache.empire.db.DBColumn;
+import org.apache.empire.db.DBColumnExpr;
+import org.apache.empire.db.DBDatabase;
+import org.apache.empire.xml.XMLUtil;
+import org.w3c.dom.Element;
+
+
+/**
+ * This class is used for declaring scalar functions in SQL (like e.g. random).
+ * <P>
+ *
+ */
+public class DBScalarExpr extends DBColumnExpr
+{
+    private final static long serialVersionUID = 1L;
+  
+    public final DBDatabase   db;
+    public final DataType     dataType;
+    public final String       template;
+    protected Object[]        params;
+
+    /**
+     * Constructs a new DBValueExpr object.
+     * 
+     * @param db the database
+     * @param value the value for this constant
+     * @param type the data type for this constant
+     */
+    public DBScalarExpr(DBDatabase db, String template, Object[] params, DataType dataType)
+    {
+        this.db = db;
+        this.dataType = dataType;
+        this.template = template;
+        this.params = params;
+    }
+
+    /**
+     * Constructs a new DBValueExpr object.
+     * 
+     * @param db the database
+     * @param value the value for this constant
+     * @param type the data type for this constant
+     */
+    public DBScalarExpr(DBDatabase db, String template, Object param, DataType dataType)
+    {
+        this.db = db;
+        this.dataType = dataType;
+        this.template = template;
+        this.params = new Object[] { param };
+    }
+    
+    /**
+     * return the value associated with this value expression
+     * @return the current value
+     */
+    public Object[] getParams()
+    {
+        return params;
+    }
+
+    /**
+     * set the value associated with this value expression
+     * @param the value
+     */
+    public void setParams(Object[] params)
+    {
+        this.params = params;
+    }
+
+    /**
+     * Returns the current DBDatabase object.
+     * 
+     * @return the current DBDatabase object
+     */
+    @Override
+    public DBDatabase getDatabase()
+    {
+        return db;
+    }
+
+    /**
+     * Returns the data type of the DBColumnExpr object.
+     * 
+     * @return the data type
+     */
+    @Override
+    public DataType getDataType()
+    {
+        return dataType;
+    }
+
+    /**
+     * Returns the column name.
+     * 
+     * @return the column name
+     */
+    @Override
+    public String getName()
+    {
+        return null;
+    }
+
+    /** this helper function calls the DBColumnExpr.addXML(Element, long) method */
+    @Override
+    public Element addXml(Element parent, long flags)
+    {
+        Element elem;
+        // Add a column expression for this function
+        elem = XMLUtil.addElement(parent, "column");
+        String name = getName();
+        if (name!=null)
+            elem.setAttribute("name", getName());
+        // Add Other Attributes
+        if (attributes!=null)
+            attributes.addXml(elem, flags);
+        // Done
+        elem.setAttribute("function", template);
+        return elem;
+    }
+
+    /**
+     * Returns null.
+     * 
+     * @return null
+     */
+    @Override
+    public DBColumn getUpdateColumn()
+    {
+        return null;
+    }
+
+    /**
+     * Always returns false since value expressions cannot be an aggregate.
+     * 
+     * @return false
+     */
+    @Override
+    public boolean isAggregate()
+    {
+        return false;
+    }
+
+    /**
+     * @see org.apache.empire.db.DBExpr#addReferencedColumns(Set)
+     */
+    @Override
+    public void addReferencedColumns(Set<DBColumn> list)
+    {
+        return;
+    }
+
+    /**
+     * Creates the SQL-Command.
+     * 
+     * @param buf the SQL-Command
+     * @param context the current SQL-Command context
+     */
+    @Override
+    public void addSQL(StringBuilder buf, long context)
+    {
+        // Get Text from Template
+        String text = this.template;
+        if (params != null)
+        {   // Replace Params
+            for (int i = 0; i < params.length; i++)
+            {   // String test  =(params[i] != null) ? params[i].toString() : "";
+                String value = getObjectValue(dataType, params[i], CTX_DEFAULT, ",");
+                text = StringUtils.replaceAll(template, "{"+ String.valueOf(i) + "}", value);
+            }
+        }
+        buf.append(text);
+    }
+
+}


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