OutputStream fos) throws Exception {
int failures = 0;
InetSocketAddress targetAddr = null;
TreeSet<DatanodeInfo> deadNodes = new TreeSet<DatanodeInfo>();
Socket s = null;
BlockReader blockReader = null;
ExtendedBlock block = lblock.getBlock();
while (s == null) {
DatanodeInfo chosenNode;
try {
chosenNode = bestNode(dfs, lblock.getLocations(), deadNodes);
targetAddr = NetUtils.createSocketAddr(chosenNode.getXferAddr());
} catch (IOException ie) {
if (failures >= DFSConfigKeys.DFS_CLIENT_MAX_BLOCK_ACQUIRE_FAILURES_DEFAULT) {
throw new IOException("Could not obtain block " + lblock);
}
LOG.info("Could not obtain block from any node: " + ie);
try {
Thread.sleep(10000);
} catch (InterruptedException iex) {
}
deadNodes.clear();
failures++;
continue;
}
try {
s = new Socket();
s.connect(targetAddr, HdfsServerConstants.READ_TIMEOUT);
s.setSoTimeout(HdfsServerConstants.READ_TIMEOUT);
String file = BlockReaderFactory.getFileName(targetAddr, block.getBlockPoolId(),
block.getBlockId());
blockReader = BlockReaderFactory.newBlockReader(
conf, s, file, block, lblock
.getBlockToken(), 0, -1);
} catch (IOException ex) {
// Put chosen node into dead list, continue
LOG.info("Failed to connect to " + targetAddr + ":" + ex);
deadNodes.add(chosenNode);
if (s != null) {
try {
s.close();
} catch (IOException iex) {
}
}
s = null;
}
}
if (blockReader == null) {
throw new Exception("Could not open data stream for " + lblock.getBlock());
}
byte[] buf = new byte[1024];
int cnt = 0;
boolean success = true;
long bytesRead = 0;
try {
while ((cnt = blockReader.read(buf, 0, buf.length)) > 0) {
fos.write(buf, 0, cnt);
bytesRead += cnt;
}
if ( bytesRead != block.getNumBytes() ) {
throw new IOException("Recorded block size is " + block.getNumBytes() +