| /* |
| * 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.backend.executionengine; |
| |
| import java.io.OutputStream; |
| import java.io.Serializable; |
| import java.util.Map; |
| |
| import org.apache.pig.impl.logicalLayer.LogicalOperator; |
| import org.apache.pig.impl.logicalLayer.OperatorKey; |
| |
| /** |
| * A logical plan has a root of the operator tree. |
| * A table of operators collects the set of operators making up a logical tree. |
| * It is possible to navigate a logical tree by looking up the input operator |
| * keys of the logical operator in the operator table. |
| * |
| */ |
| public interface ExecLogicalPlan extends Serializable { |
| |
| public OperatorKey getRoot(); |
| |
| public Map<OperatorKey, LogicalOperator> getOpTable(); |
| |
| public void explain(OutputStream out); |
| } |