/*
* 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.jena.sdb.core.sqlnode;
public class SqlTransformCopy implements SqlTransform
{
public static final boolean COPY_ALWAYS = true ;
public static final boolean COPY_ONLY_ON_CHANGE = false ;
private boolean alwaysCopy = false ;
public SqlTransformCopy() { this(COPY_ONLY_ON_CHANGE) ; }
public SqlTransformCopy(boolean alwaysDuplicate) { this.alwaysCopy = alwaysDuplicate ; }
@Override
public SqlNode transform(SqlProject sqlProject, SqlNode subNode)
{ return xform(sqlProject, subNode) ; }
public SqlNode transform(SqlDistinct sqlDistinct, SqlNode subNode)
{ return xform(sqlDistinct, subNode) ; }
@Override
public SqlNode transform(SqlRestrict sqlRestrict, SqlNode subNode)
{ return xform(sqlRestrict, subNode) ; }
public SqlNode transform(SqlSlice sqlSlice, SqlNode subNode)
{ return xform(sqlSlice, subNode) ; }
@Override
public SqlNode transform(SqlSelectBlock sqlSelectBlock, SqlNode subNode)
{ return xform(sqlSelectBlock, subNode) ; }
@Override
public SqlNode transform(SqlJoinInner sqlJoinInner, SqlNode left, SqlNode right)
{ return xform(sqlJoinInner, left, right) ; }
@Override
public SqlNode transform(SqlJoinLeftOuter sqlJoinLeftOuter, SqlNode left, SqlNode right)
{ return xform(sqlJoinLeftOuter, left, right) ; }
@Override
public SqlNode transform(SqlUnion sqlUnion, SqlNode left, SqlNode right)
{ return xform(sqlUnion, left, right) ; }
@Override
public SqlNode transform(SqlTable sqlTable)
{ return xform(sqlTable) ; }
@Override
public SqlNode transform(SqlRename sqlRename, SqlNode subNode)
{ return xform(sqlRename, subNode) ; }
@Override
public SqlNode transform(SqlCoalesce sqlCoalesce, SqlNode subNode)
{ return xform(sqlCoalesce, subNode) ; }
// ---- Workers
private SqlNode xform(SqlNodeBase0 sqlNode)
{
if ( ! alwaysCopy )
return sqlNode ;
return sqlNode.copy() ;
}
private SqlNode xform(SqlNodeBase1 sqlNode, SqlNode subNode)
{
if ( ! alwaysCopy && sqlNode.getSubNode() == subNode )
return sqlNode ;
return sqlNode.copy(subNode) ;
}
private SqlNode xform(SqlNodeBase2 sqlNode, SqlNode left, SqlNode right)
{
if ( ! alwaysCopy && sqlNode.getLeft() == left && sqlNode.getRight() == right )
return sqlNode ;
return sqlNode.copy(left, right) ;
}
}