/*
* 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.pig.impl.logicalLayer;
import java.util.HashSet;
import java.util.List;
import java.util.Set;
import java.util.ArrayList;
import org.apache.pig.FuncSpec;
import org.apache.pig.impl.plan.DepthFirstWalker;
import org.apache.pig.impl.plan.VisitorException;
/**
* A visitor to track the casts in a plan.
*/
public class CastFinder extends LOVisitor {
List<LOCast> mCastList = new ArrayList<LOCast>();
/**
*
* @param plan
* logical plan to query the presence of UDFs
*/
public CastFinder(LogicalPlan plan) {
super(plan, new DepthFirstWalker<LogicalOperator, LogicalPlan>(plan));
}
/*
* (non-Javadoc)
*
* @see
* org.apache.pig.impl.logicalLayer.LOVisitor#visit(org.apache.pig.impl.
* logicalLayer.LOUserFunc)
*/
@Override
protected void visit(LOCast cast) throws VisitorException {
mCastList.add(cast);
}
/**
*
* @return list of casts found in the plan
*/
public List<LOCast> getCastList() {
return mCastList;
}
/**
*
* @return set of casts found in the plan
*/
public Set<LOCast> getCastSet() {
return new HashSet<LOCast>(mCastList);
}
/**
*
* @return true if the plan contained any Casts; false otherwise
*/
public boolean foundAnyCast() {
return (mCastList.size() == 0 ? false : true);
}
}