TestBlocksScheduledCounter.java
上传用户:quxuerui
上传日期:2018-01-08
资源大小:41811k
文件大小:2k
源码类别:
网格计算
开发平台:
Java
- /**
- * 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 java.io.IOException;
- import java.util.ArrayList;
- import org.apache.hadoop.conf.Configuration;
- import org.apache.hadoop.hdfs.DFSClient.DFSOutputStream;
- import org.apache.hadoop.hdfs.server.namenode.DatanodeDescriptor;
- import org.apache.hadoop.fs.FSDataOutputStream;
- import org.apache.hadoop.fs.FileSystem;
- import org.apache.hadoop.fs.Path;
- import junit.framework.TestCase;
- /**
- * This class tests DatanodeDescriptor.getBlocksScheduled() at the
- * NameNode. This counter is supposed to keep track of blocks currently
- * scheduled to a datanode.
- */
- public class TestBlocksScheduledCounter extends TestCase {
- public void testBlocksScheduledCounter() throws IOException {
- MiniDFSCluster cluster = new MiniDFSCluster(new Configuration(), 1,
- true, null);
- cluster.waitActive();
- FileSystem fs = cluster.getFileSystem();
- //open a file an write a few bytes:
- FSDataOutputStream out = fs.create(new Path("/testBlockScheduledCounter"));
- for (int i=0; i<1024; i++) {
- out.write(i);
- }
- // flush to make sure a block is allocated.
- ((DFSOutputStream)(out.getWrappedStream())).sync();
- ArrayList<DatanodeDescriptor> dnList = new ArrayList<DatanodeDescriptor>();
- cluster.getNameNode().namesystem.DFSNodesStatus(dnList, dnList);
- DatanodeDescriptor dn = dnList.get(0);
- assertEquals(1, dn.getBlocksScheduled());
- // close the file and the counter should go to zero.
- out.close();
- assertEquals(0, dn.getBlocksScheduled());
- }
- }