/*
* 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.flink.streaming.util;
import java.io.File;
import java.net.URI;
import org.apache.flink.api.java.tuple.Tuple1;
import org.apache.flink.runtime.fs.hdfs.HadoopFileSystem;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.fs.Path;
/**
* Utility for copying from a HDFS {@link FileSystem} to the local file system.
*/
public class HDFSCopyToLocal {
public static void copyToLocal(final URI remotePath,
final File localPath) throws Exception {
// Do it in another Thread because HDFS can deadlock if being interrupted while copying
String threadName = "HDFS Copy from " + remotePath + " to " + localPath;
final Tuple1<Exception> asyncException = Tuple1.of(null);
Thread copyThread = new Thread(threadName) {
@Override
public void run() {
try {
Configuration hadoopConf = HadoopFileSystem.getHadoopConfiguration();
FileSystem fs = FileSystem.get(remotePath, hadoopConf);
fs.copyToLocalFile(new Path(remotePath), new Path(localPath.getAbsolutePath()));
} catch (Exception t) {
asyncException.f0 = t;
}
}
};
copyThread.setDaemon(true);
copyThread.start();
copyThread.join();
if (asyncException.f0 != null) {
throw asyncException.f0;
}
}
}