Thread synchronization : Lock Synchronize « Threads « Java

Thread synchronization

Thread synchronization
public class TwoObjects extends Object {
  private String objID;

  public TwoObjects(String objID) {
    this.objID = objID;

  public synchronized void synchronizedMethod(int val) {
    print("entering synchronized method()");
    int num = val * 2 + objID.length();
    print("in doStuff() - local variable num=" + num);

    try {
    } catch (InterruptedException x) {

    print("leaving synchronized method");

  public void print(String msg) {
    threadPrint("objID=" + objID + " - " + msg);

  public static void threadPrint(String msg) {
    String threadName = Thread.currentThread().getName();
    System.out.println(threadName + ": " + msg);

  public static void main(String[] args) {
    final TwoObjects obj1 = new TwoObjects("obj1");
    final TwoObjects obj2 = new TwoObjects("obj2");

    Runnable runA = new Runnable() {
      public void run() {

    Thread threadA = new Thread(runA, "threadA");

    try {
    } catch (InterruptedException x) {

    Runnable runB = new Runnable() {
      public void run() {

    Thread threadB = new Thread(runB, "threadB");


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