org.apache.pig.newplan.logical.rules.WholePlanRule Maven / Gradle / Ivy
/**
* 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.newplan.logical.rules;
import java.util.ArrayList;
import java.util.List;
import org.apache.pig.newplan.OperatorPlan;
import org.apache.pig.newplan.optimizer.Rule;
/**
* Super class for all rules that operates on the whole plan. It doesn't look for
* a specific pattern. An example of such kind rule is ColumnPrune.
*
*/
public abstract class WholePlanRule extends Rule {
public WholePlanRule(String n, boolean mandatory) {
super(n, mandatory);
}
public List match(OperatorPlan plan) {
currentPlan = plan;
List ll = new ArrayList();
ll.add(plan);
return ll;
}
@Override
protected OperatorPlan buildPattern() {
return null;
}
}