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Posted to commits@empire-db.apache.org by do...@apache.org on 2016/03/07 18:54:18 UTC
empire-db git commit: EMPIREDB-238 added column expression for scalar
functions
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 <do...@apache.org>
Authored: Mon Mar 7 18:54:12 2016 +0100
Committer: Rainer Döbele <do...@apache.org>
Committed: Mon Mar 7 18:54:12 2016 +0100
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.../empire/db/expr/column/DBScalarExpr.java | 199 +++++++++++++++++++
1 file changed, 199 insertions(+)
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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
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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);
+ }
+
+}