public synchronized InputStream getBlockInputStream(Block b, long seekOffset) throws IOException {
File blockFile = getBlockFile(b);
RandomAccessFile blockInFile = new RandomAccessFile(blockFile, "r");
if (seekOffset > 0) {
blockInFile.seek(seekOffset);
}
return new FileInputStream(blockInFile.getFD());
}
/** Returns handles to the block file and its metadata file */
public synchronized BlockInputStreams getTmpInputStreams(Block b, long blkOffset, long ckoff)
throws IOException {
DatanodeBlockInfo info = volumeMap.get(b);
if (info == null) {
throw new IOException("Block " + b + " does not exist in volumeMap.");
}
FSVolume v = info.getVolume();
File blockFile = v.getTmpFile(b);
RandomAccessFile blockInFile = new RandomAccessFile(blockFile, "r");
if (blkOffset > 0) {
blockInFile.seek(blkOffset);
}
File metaFile = getMetaFile(blockFile, b);
RandomAccessFile metaInFile = new RandomAccessFile(metaFile, "r");
if (ckoff > 0) {
metaInFile.seek(ckoff);
}
return new BlockInputStreams(
new FileInputStream(blockInFile.getFD()), new FileInputStream(metaInFile.getFD()));
}