/**
* 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.hdfs;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.io.IOUtils;
import java.io.OutputStream;
import org.junit.Test;
/**
* Regression test for HDFS-1542, a deadlock between the main thread
* and the DFSOutputStream.DataStreamer thread caused because
* Configuration.writeXML holds a lock on itself while writing to DFS.
*/
public class TestWriteConfigurationToDFS {
@Test(timeout=60000)
public void testWriteConf() throws Exception {
Configuration conf = new HdfsConfiguration();
conf.setInt(DFSConfigKeys.DFS_BLOCK_SIZE_KEY, 4096);
System.out.println("Setting conf in: " + System.identityHashCode(conf));
MiniDFSCluster cluster = new MiniDFSCluster.Builder(conf).numDataNodes(1).build();
FileSystem fs = null;
OutputStream os = null;
try {
fs = cluster.getFileSystem();
Path filePath = new Path("/testWriteConf.xml");
os = fs.create(filePath);
StringBuilder longString = new StringBuilder();
for (int i = 0; i < 100000; i++) {
longString.append("hello");
} // 500KB
conf.set("foobar", longString.toString());
conf.writeXml(os);
os.close();
os = null;
fs.close();
fs = null;
} finally {
IOUtils.cleanup(null, os, fs);
cluster.shutdown();
}
}
}