| /* |
| * 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; |
| |
| import java.util.HashMap; |
| import java.util.Map; |
| |
| import org.apache.pig.impl.logicalLayer.FrontendException; |
| import org.apache.pig.parser.SourceLocation; |
| |
| public abstract class Operator { |
| protected SourceLocation location; // The location of the operator in the original pig script. |
| |
| protected String name; |
| protected OperatorPlan plan; // plan that contains this operator |
| protected Map<String, Object> annotations; |
| protected final int hashPrime = 31; |
| |
| public Operator(String n, OperatorPlan p) { |
| name = n; |
| plan = p; |
| annotations = new HashMap<String, Object>(); |
| location = new SourceLocation(); |
| } |
| |
| /** |
| * Accept a visitor at this node in the graph. |
| * @param v Visitor to accept. |
| * @throws FrontendException |
| */ |
| public abstract void accept(PlanVisitor v) throws FrontendException; |
| |
| public String getName() { |
| return name; |
| } |
| |
| public SourceLocation getLocation() { |
| return location; |
| } |
| |
| public void setLocation(SourceLocation loc) { |
| location = loc; |
| } |
| |
| /** |
| * Get the plan associated with this operator. |
| * @return plan |
| */ |
| public OperatorPlan getPlan() { |
| return plan; |
| } |
| |
| /** |
| * Add an annotation to a node in the plan. |
| * @param key string name of this annotation |
| * @param val value, as an Object |
| */ |
| public void annotate(String key, Object val) { |
| annotations.put(key, val); |
| } |
| |
| /** |
| * Look to see if a node is annotated. |
| * @param key string name of annotation to look for |
| * @return value of the annotation, as an Object, or null if the key is |
| * not present in the map. |
| */ |
| public Object getAnnotation(String key) { |
| return annotations.get(key); |
| } |
| |
| /** |
| * Remove an annotation |
| * @param key the key of the annotation |
| * @return the original value of the annotation |
| */ |
| public Object removeAnnotation(String key) { |
| return annotations.remove(key); |
| } |
| |
| public void setPlan(OperatorPlan p) { |
| plan = p; |
| } |
| |
| /** |
| * This is like a shallow equals comparison. |
| * It returns true if two operators have equivalent properties even if they are |
| * different objects. Here properties mean equivalent plan and equivalent name. |
| * @param operator |
| * @return true if two object have equivalent properties, else false |
| */ |
| public abstract boolean isEqual(Operator operator) throws FrontendException; |
| } |