/** Get a BlockReader for the given block. */
public BlockReader getBlockReader(LocatedBlock testBlock, int offset, int lenToRead)
throws IOException {
InetSocketAddress targetAddr = null;
Socket sock = null;
ExtendedBlock block = testBlock.getBlock();
DatanodeInfo[] nodes = testBlock.getLocations();
targetAddr = NetUtils.createSocketAddr(nodes[0].getName());
sock = NetUtils.getDefaultSocketFactory(conf).createSocket();
sock.connect(targetAddr, HdfsServerConstants.READ_TIMEOUT);
sock.setSoTimeout(HdfsServerConstants.READ_TIMEOUT);
return BlockReaderFactory.newBlockReader(
new DFSClient.Conf(conf),
sock,
targetAddr.toString() + ":" + block.getBlockId(),
block,
testBlock.getBlockToken(),
offset,
lenToRead,
conf.getInt("io.file.buffer.size", 4096),
true,
"");
}
