lockmanagertest.java

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package lockmgr;

import java.util.*;

class LockManagerTest {
    
    static LockManager lm = new LockManager();

    public static void main (String[] args) {
	test1();
	//test2();
    }

    static void test1()
    {
	System.out.println("Deadlock test");

	Transaction t1 = new Transaction(1, "rl a sl 3000 wl b ua");
	Transaction t2 = new Transaction(2, "rl b sl 10 wl a ua");
	t1.start();
	t2.start();
    }

    static void test2()
    {
	System.out.println("Lock conversion test");
	Transaction t1 = new Transaction(1, "rl a sl 10 wl a ua");
	Transaction t2 = new Transaction(2, "rl a sl 2000 ua"); 
	t1.start();
	t2.start();
    }
	

    static class Transaction extends Thread {
	
	int xid;
	StringTokenizer st;
	
	public Transaction(int xid, String ops) 
	{
	    this.xid = xid;
	    st = new StringTokenizer(ops);
	}
	
	public void run()
	{
	    try {
		while (st.hasMoreTokens()) {
		    String opcode = st.nextToken();

		    if (opcode.equalsIgnoreCase("rl")) {
			String param = st.nextToken();
			lm.lock(xid, param, LockManager.READ);
			System.out.println("Transaction " + xid +
					   " got rl(" + param + ")");
		    }
		    else if (opcode.equalsIgnoreCase("wl")) {
			String param = st.nextToken();
			lm.lock(xid, param, LockManager.WRITE);
			System.out.println("Transaction " + xid +
					   " got wl(" + param + ")");
		    }
		    else if (opcode.equalsIgnoreCase("ua")) {
			lm.unlockAll(xid);
		    }
		    else if (opcode.equalsIgnoreCase("sl")) {
			String param = st.nextToken();
			int sleepTime = Integer.parseInt(param);
			try {
			    this.sleep(sleepTime);
			}
			catch (InterruptedException ie) {
			}
		    }
		    else {
			System.out.println("Unknown opcode " + opcode);
			break;
		    }
		}
	    }
	    catch (DeadlockException de) {
		System.out.println("Transaction " + xid + ": Deadlock...");
	    }
	    finally {
		lm.unlockAll(xid);
	    }
	}
    }
}