How to use

isUnlinked

method

in

org.apache.hadoop.hdfs.server.datanode.ReplicaInfo

@Override //ReplicaInfo
public boolean isUnlinked() {
 return original.isUnlinked();
}

@Override //ReplicaInfo
public boolean isUnlinked() {
 return original.isUnlinked();
}

/**
 * Remove a hard link by copying the block to a temporary place and 
 * then moving it back
 * @param numLinks number of hard links
 * @return true if copy is successful; 
 *         false if it is already detached or no need to be detached
 * @throws IOException if there is any copy error
 */
public boolean unlinkBlock(int numLinks) throws IOException {
 if (isUnlinked()) {
  return false;
 }
 File file = getBlockFile();
 if (file == null || getVolume() == null) {
  throw new IOException("detachBlock:Block not found. " + this);
 }
 File meta = getMetaFile();
 if (HardLink.getLinkCount(file) > numLinks) {
  DataNode.LOG.info("CopyOnWrite for block " + this);
  unlinkFile(file, this);
 }
 if (HardLink.getLinkCount(meta) > numLinks) {
  unlinkFile(meta, this);
 }
 setUnlinked();
 return true;
}

/**
 * Remove a hard link by copying the block to a temporary place and 
 * then moving it back
 * @param numLinks number of hard links
 * @return true if copy is successful; 
 *         false if it is already detached or no need to be detached
 * @throws IOException if there is any copy error
 */
public boolean unlinkBlock(int numLinks) throws IOException {
 if (isUnlinked()) {
  return false;
 }
 File file = getBlockFile();
 if (file == null || getVolume() == null) {
  throw new IOException("detachBlock:Block not found. " + this);
 }
 File meta = getMetaFile();
 if (HardLink.getLinkCount(file) > numLinks) {
  DataNode.LOG.info("CopyOnWrite for block " + this);
  unlinkFile(file, this);
 }
 if (HardLink.getLinkCount(meta) > numLinks) {
  unlinkFile(meta, this);
 }
 setUnlinked();
 return true;
}