How to use

setTransactionId

method

in

org.apache.hadoop.hdfs.server.namenode.FSEditLogOp

@Override
public FSEditLogOp decodeOp() throws IOException {
 limiter.setLimit(maxOpSize);
 in.mark(maxOpSize);
 byte opCodeByte;
 try {
  opCodeByte = in.readByte();
 } catch (EOFException eof) {
  // EOF at an opcode boundary is expected.
  return null;
 }
 FSEditLogOpCodes opCode = FSEditLogOpCodes.fromByte(opCodeByte);
 if (opCode == OP_INVALID) {
  verifyTerminator();
  return null;
 }
 FSEditLogOp op = cache.get(opCode);
 if (op == null) {
  throw new IOException("Read invalid opcode " + opCode);
 }
 if (NameNodeLayoutVersion.supports(
    LayoutVersion.Feature.STORED_TXIDS, logVersion)) {
  op.setTransactionId(in.readLong());
 } else {
  op.setTransactionId(HdfsServerConstants.INVALID_TXID);
 }
 op.readFields(in, logVersion);
 return op;
}

synchronized boolean doEditTransaction(final FSEditLogOp op) {
 long start = beginTransaction();
 op.setTransactionId(txid);
 try {
  editLogStream.write(op);
 } catch (IOException ex) {
  // All journals failed, it is handled in logSync.
 } finally {
  op.reset();
 }
 endTransaction(start);
 return shouldForceSync();
}

 throw new IOException("Read invalid opcode " + opCode);
op.setTransactionId(in.readLong());
op.readFields(in, logVersion);

@Override
public FSEditLogOp decodeOp() throws IOException {
 long txid = decodeOpFrame();
 if (txid == HdfsServerConstants.INVALID_TXID) {
  return null;
 }
 in.reset();
 in.mark(maxOpSize);
 FSEditLogOpCodes opCode = FSEditLogOpCodes.fromByte(in.readByte());
 FSEditLogOp op = cache.get(opCode);
 if (op == null) {
  throw new IOException("Read invalid opcode " + opCode);
 }
 op.setTransactionId(txid);
 IOUtils.skipFully(in, 4 + 8); // skip length and txid
 op.readFields(in, logVersion);
 // skip over the checksum, which we validated above.
 IOUtils.skipFully(in, CHECKSUM_LENGTH);
 return op;
}

op.setTransactionId(nextTxId);
nextTxId++;

op.setTransactionId(nextTxId);
nextTxId++;

op.setTransactionId(in.readLong());

  LayoutVersion.Feature.STORED_TXIDS, logVersion)) {
 op.setTransactionId(in.readLong());
} else {
 op.setTransactionId(HdfsConstants.INVALID_TXID);

public static void writeOp(EditLogOutputStream stm, long txid) throws IOException {
 FSEditLogOp op = NameNodeAdapter.createMkdirOp("tx " + txid);
 op.setTransactionId(txid);
 stm.write(op);
}

  LayoutVersion.Feature.STORED_TXIDS, logVersion)) {
 op.setTransactionId(in.readLong());
} else {
 op.setTransactionId(HdfsConstants.INVALID_TXID);

op.setTransactionId(txid);
assert this.getNumEditStreams() > 0 : "no editlog streams";
long start = FSNamesystem.now();

op.setTransactionId(nextTxId);
nextTxId++;

op.setTransactionId(nextTxId);
nextTxId++;

op.setTransactionId(nextTxId);
nextTxId++;

public static byte[] createTxnData(int startTxn, int numTxns) throws Exception {
 DataOutputBuffer buf = new DataOutputBuffer();
 FSEditLogOp.Writer writer = new FSEditLogOp.Writer(buf);
 
 for (long txid = startTxn; txid < startTxn + numTxns; txid++) {
  FSEditLogOp op = NameNodeAdapter.createMkdirOp("tx " + txid);
  op.setTransactionId(txid);
  writer.writeOp(op);
 }
 
 return Arrays.copyOf(buf.getData(), buf.getLength());
}

/**
 * Generate byte array representing a set of GarbageMkdirOp
 */
public static byte[] createGabageTxns(long startTxId, int numTxns)
  throws IOException {
 DataOutputBuffer buf = new DataOutputBuffer();
 FSEditLogOp.Writer writer = new FSEditLogOp.Writer(buf);
 for (long txid = startTxId; txid < startTxId + numTxns; txid++) {
  FSEditLogOp op = new TestEditLog.GarbageMkdirOp();
  op.setTransactionId(txid);
  writer.writeOp(op);
 }
 return Arrays.copyOf(buf.getData(), buf.getLength());
}

op.setTransactionId(txid);

op.setTransactionId(txid);

op.setTransactionId(nextTxId);
nextTxId++;