| /** |
| * 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.tajo.engine.planner.physical; |
| |
| import org.apache.tajo.plan.Target; |
| import org.apache.tajo.plan.logical.EvalExprNode; |
| import org.apache.tajo.storage.Tuple; |
| import org.apache.tajo.storage.VTuple; |
| import org.apache.tajo.worker.TaskAttemptContext; |
| |
| import java.io.IOException; |
| |
| public class EvalExprExec extends PhysicalExec { |
| private final EvalExprNode plan; |
| private float progress; |
| private boolean executedOnce = false; |
| |
| public EvalExprExec(final TaskAttemptContext context, final EvalExprNode plan) { |
| super(context, plan.getInSchema(), plan.getOutSchema()); |
| this.plan = plan; |
| } |
| |
| @Override |
| public void init() throws IOException { |
| super.init(); |
| progress = 0.0f; |
| for (Target target : plan.getTargets()) { |
| target.getEvalTree().bind(context.getEvalContext(), inSchema); |
| } |
| } |
| |
| @Override |
| public Tuple next() throws IOException { |
| if (!executedOnce) { |
| Target [] targets = plan.getTargets(); |
| Tuple t = new VTuple(targets.length); |
| for (int i = 0; i < targets.length; i++) { |
| t.put(i, targets[i].getEvalTree().eval(null)); |
| } |
| |
| executedOnce = true; |
| return t; |
| } else { |
| return null; |
| } |
| } |
| |
| @Override |
| public void rescan() throws IOException { |
| executedOnce = false; |
| } |
| |
| @Override |
| public void close() throws IOException { |
| progress = 1.0f; |
| } |
| |
| @Override |
| public float getProgress() { |
| return progress; |
| } |
| } |