DfsBaseConditional.java
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上传日期:2018-01-08
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文件大小:2k
- /**
- * 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.hadoop.ant.condition;
- import org.apache.tools.ant.taskdefs.condition.Condition;
- /**
- * This wrapper around {@link org.apache.hadoop.ant.DfsTask} implements the
- * Ant >1.5
- * {@link org.apache.tools.ant.taskdefs.condition.Condition Condition}
- * interface for HDFS tests. So one can test conditions like this:
- * {@code
- * <condition property="precond">
- * <and>
- * <hadoop:exists file="fileA" />
- * <hadoop:exists file="fileB" />
- * <hadoop:sizezero file="fileB" />
- * </and>
- * </condition>
- * }
- * This will define the property precond if fileA exists and fileB has zero
- * length.
- */
- public abstract class DfsBaseConditional extends org.apache.hadoop.ant.DfsTask
- implements Condition {
- protected boolean result;
- String file;
- private void initArgs() {
- setCmd("test");
- setArgs("-" + getFlag() + "," + file);
- }
- public void setFile(String file) {
- this.file = file;
- }
- protected abstract char getFlag();
- protected int postCmd(int exit_code) {
- exit_code = super.postCmd(exit_code);
- result = exit_code == 1;
- return exit_code;
- }
- public boolean eval() {
- initArgs();
- execute();
- return result;
- }
- }