package simpledb.tx.recovery;

import simpledb.log.*;
import java.util.*;

public class NQCheckpointRecord implements LogRecord {
	private List<Integer> txs = new ArrayList<Integer>();

	public int writeToLog() {
		int size = txs.size();
		Object[] rec = new Object[size+2];
		rec[0] = NQCKPT;
		rec[1] = size;
		for (int i=0; i<size; i++)
			rec[i+2] = txs.get(i);
		return logMgr.append(rec);
	}

	public NQCheckpointRecord(List<Integer> txs) {
		this.txs = txs;
	}
	
	public NQCheckpointRecord(BasicLogRecord rec) {
		int size = rec.nextInt();
		for (int i=0; i<size; i++)
			txs.add(new Integer(rec.nextInt()));
	}

	public List<Integer> txs() {
		return txs;
	}

	public int op() {
		return LogRecord.NQCKPT;
	}

	public int txNumber() {
		return -1; // dummy value
	}

	public void undo(int txnum) {}

	public String toString() {
		String result = "<NQCHECKPOINT ";
		for (Integer i : txs)
			result += i + " ";
		return result + ">";
	}
}