SynchronizedMethod2.java
/*
* Copyright@ 2011 www.egtry.com
*/
package egtry.thread;
///two synchronized method1 and method2, while a thread is executing the method1, other threads can not executing the method2
public class SynchronizedMethod2 extends Thread {
private Counter counter;
public static void main(String[] args) {
Counter counter=new Counter();
for(int i=0; i<10; i++) {
SynchronizedMethod2 t=new SynchronizedMethod2(counter);
t.start();
}
}
public SynchronizedMethod2(Counter counter) {
this.counter=counter;
}
@Override
public void run() {
int id=counter.get();
counter.sleep();
counter.inc();
}
static class Counter {
private int counter=0;
public synchronized int get() {
System.out.println("get() Enter: ("+Thread.currentThread().getId()+") value="+counter);
sleep();
System.out.println("get() Exit: ("+Thread.currentThread().getId()+") value="+counter);
System.out.println("\n");
return counter;
}
public synchronized int inc() {
System.out.println("inc() Enter: ("+Thread.currentThread().getId()+") value="+counter);
sleep();
counter++;
sleep();
System.out.println("inc() Exit: ("+Thread.currentThread().getId()+") value="+counter);
System.out.println("\n");
return counter;
}
public void sleep() {
int millis=(int)Math.random()*1000;
try {
Thread.sleep(millis);
} catch (Exception e) {
}
}
}
}
Output
get() Enter: (8) value=0
get() Exit: (8) value=0
get() Enter: (10) value=0
get() Exit: (10) value=0
get() Enter: (15) value=0
get() Exit: (15) value=0
get() Enter: (12) value=0
get() Exit: (12) value=0
inc() Enter: (12) value=0
inc() Exit: (12) value=1
get() Enter: (17) value=1
get() Exit: (17) value=1
inc() Enter: (15) value=1
inc() Exit: (15) value=2
get() Enter: (9) value=2
get() Exit: (9) value=2
inc() Enter: (10) value=2
inc() Exit: (10) value=3
get() Enter: (11) value=3
get() Exit: (11) value=3
get() Enter: (16) value=3
get() Exit: (16) value=3
get() Enter: (13) value=3
get() Exit: (13) value=3
inc() Enter: (8) value=3
inc() Exit: (8) value=4
get() Enter: (14) value=4
get() Exit: (14) value=4
inc() Enter: (16) value=4
inc() Exit: (16) value=5
inc() Enter: (11) value=5
inc() Exit: (11) value=6
inc() Enter: (9) value=6
inc() Exit: (9) value=7
inc() Enter: (17) value=7
inc() Exit: (17) value=8
inc() Enter: (13) value=8
inc() Exit: (13) value=9
inc() Enter: (14) value=9
inc() Exit: (14) value=10