Hadoop 2.7.1 使用minicluster进行单元测试

目的是要跑通这个单元测试:hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/TestClose.java

这个Java文件比较简单：

/**

 * 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

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package org.apache.hadoop.hdfs;

import static org.junit.Assert.fail;

import java.io.IOException;

import java.io.OutputStream;

import java.nio.channels.ClosedChannelException;

import org.apache.hadoop.conf.Configuration;

import org.apache.hadoop.fs.FileSystem;

import org.apache.hadoop.fs.Path;

import org.apache.hadoop.test.GenericTestUtils;

import org.junit.Test;

public class TestClose {

  @Test

  public void testWriteAfterClose() throws IOException {

    Configuration conf = new Configuration();

    MiniDFSCluster cluster = new MiniDFSCluster.Builder(conf)

        .build();

    try {

      final byte[] data = "foo".getBytes();

      FileSystem fs = FileSystem.get(conf);

      OutputStream out = fs.create(new Path("/test"));

      out.write(data);

      out.close();

      try {

        // Should fail.

        out.write(data);

        fail("Should not have been able to write more data after file is closed.");

      } catch (ClosedChannelException cce) {

        // We got the correct exception. Ignoring.

      }

      // Should succeed. Double closes are OK.

      out.close();

    } finally {

      if (cluster != null) {

        cluster.shutdown();

      }

    }

  }

}