Java MiniDFSCluster.getRbwDir方法代码示例

import org.apache.hadoop.hdfs.MiniDFSCluster; //导入方法依赖的package包/类
/**
 * Test to check that a DN goes down when all its volumes have failed.
 */
@Test
public void testShutdown() throws Exception {
  if (System.getProperty("os.name").startsWith("Windows")) {
    /**
     * This test depends on OS not allowing file creations on a directory
     * that does not have write permissions for the user. Apparently it is 
     * not the case on Windows (at least under Cygwin), and possibly AIX.
     * This is disabled on Windows.
     */
    return;
  }
  // Bring up two more datanodes
  cluster.startDataNodes(conf, 2, true, null, null);
  cluster.waitActive();
  final int dnIndex = 0;
  String bpid = cluster.getNamesystem().getBlockPoolId();
  File storageDir = cluster.getInstanceStorageDir(dnIndex, 0);
  File dir1 = MiniDFSCluster.getRbwDir(storageDir, bpid);
  storageDir = cluster.getInstanceStorageDir(dnIndex, 1);
  File dir2 = MiniDFSCluster.getRbwDir(storageDir, bpid);
  try {
    // make the data directory of the first datanode to be readonly
    assertTrue("Couldn't chmod local vol", dir1.setReadOnly());
    assertTrue("Couldn't chmod local vol", dir2.setReadOnly());

    // create files and make sure that first datanode will be down
    DataNode dn = cluster.getDataNodes().get(dnIndex);
    for (int i=0; dn.isDatanodeUp(); i++) {
      Path fileName = new Path("/test.txt"+i);
      DFSTestUtil.createFile(fs, fileName, 1024, (short)2, 1L);
      DFSTestUtil.waitReplication(fs, fileName, (short)2);
      fs.delete(fileName, true);
    }
  } finally {
    // restore its old permission
    FileUtil.setWritable(dir1, true);
    FileUtil.setWritable(dir2, true);
  }
}
 

import org.apache.hadoop.hdfs.MiniDFSCluster; //导入方法依赖的package包/类
/**
 * Test that when there is a failure replicating a block the temporary
 * and meta files are cleaned up and subsequent replication succeeds.
 */
@Test
public void testReplicationError() throws Exception {
  // create a file of replication factor of 1
  final Path fileName = new Path("/test.txt");
  final int fileLen = 1;
  DFSTestUtil.createFile(fs, fileName, 1, (short)1, 1L);
  DFSTestUtil.waitReplication(fs, fileName, (short)1);

  // get the block belonged to the created file
  LocatedBlocks blocks = NameNodeAdapter.getBlockLocations(
      cluster.getNameNode(), fileName.toString(), 0, (long)fileLen);
  assertEquals("Should only find 1 block", blocks.locatedBlockCount(), 1);
  LocatedBlock block = blocks.get(0);

  // bring up a second datanode
  cluster.startDataNodes(conf, 1, true, null, null);
  cluster.waitActive();
  final int sndNode = 1;
  DataNode datanode = cluster.getDataNodes().get(sndNode);
  
  // replicate the block to the second datanode
  InetSocketAddress target = datanode.getXferAddress();
  Socket s = new Socket(target.getAddress(), target.getPort());
  // write the header.
  DataOutputStream out = new DataOutputStream(s.getOutputStream());

  DataChecksum checksum = DataChecksum.newDataChecksum(
      DataChecksum.Type.CRC32, 512);
  new Sender(out).writeBlock(block.getBlock(), StorageType.DEFAULT,
      BlockTokenSecretManager.DUMMY_TOKEN, "",
      new DatanodeInfo[0], new StorageType[0], null,
      BlockConstructionStage.PIPELINE_SETUP_CREATE, 1, 0L, 0L, 0L,
      checksum, CachingStrategy.newDefaultStrategy(), false, false, null);
  out.flush();

  // close the connection before sending the content of the block
  out.close();

  // the temporary block & meta files should be deleted
  String bpid = cluster.getNamesystem().getBlockPoolId();
  File storageDir = cluster.getInstanceStorageDir(sndNode, 0);
  File dir1 = MiniDFSCluster.getRbwDir(storageDir, bpid);
  storageDir = cluster.getInstanceStorageDir(sndNode, 1);
  File dir2 = MiniDFSCluster.getRbwDir(storageDir, bpid);
  while (dir1.listFiles().length != 0 || dir2.listFiles().length != 0) {
    Thread.sleep(100);
  }

  // then increase the file's replication factor
  fs.setReplication(fileName, (short)2);
  // replication should succeed
  DFSTestUtil.waitReplication(fs, fileName, (short)1);

  // clean up the file
  fs.delete(fileName, false);
}