Question

java中线程有几种状态图解

Answer 1

1. NEW, 这个最简单了,

static void NEW() {
Thread t = new Thread ();
System. out.println(t.getState());
}

输出NEW

2. RUNNABLE, 也简单, 让一个thread start, 同时代码里面不要sleep或者wait等

private static void RUNNABLE() {
Thread t = new Thread(){

public void run(){
for(int i=0; i<Integer.MAX_VALUE; i++){
System. out.println(i);
}
}

};

t.start();
}

3. BLOCKED, 这个就必须至少两个线程以上, 然后互相等待synchronized 块

private static void BLOCKED() {

final Object lock = new Object();

Runnable run = new Runnable() {

@Override
public void run() {
for(int i=0; i<Integer.MAX_VALUE; i++){

synchronized (lock) {
System. out.println(i);
}

}
}
};

Thread t1 = new Thread(run);
t1.setName( “t1”);
4. WAITING, 这个需要用到生产者消费者模型, 当生产者生产过慢的时候, 消费者就会等待生产者的下一次notify

private static void WAITING() {

final Object lock = new Object();
Thread t1 = new Thread(){
@Override
public void run() {

int i = 0;

while(true ){
synchronized (lock) {
try {
lock.wait();
} catch (InterruptedException e) {
}
System. out.println(i++);
}
}
}
};

Thread t2 = new Thread(){
@Override
public void run() {

while(true ){
synchronized (lock) {
for(int i = 0; i< 10000000; i++){
System. out.println(i);
}
lock.notifyAll();
}

}
}
};
Thread t2 = new Thread(run);
5. TIMED_WAITING, 这个仅需要在4的基础上, 在wait方法加上一个时间参数进行限制就OK了.

把4中的synchronized 块改成如下就可以了.

synchronized (lock) {
try {
lock.wait(60 * 1000L);
} catch (InterruptedException e) {
}
System. out .println(i++);
}
t2.setName( “t2”);

t1.start();
t2.start();

}

6. TERMINATED, 这个状态只要线程结束了run方法, 就会进入了…

private static void TERMINATED() {
Thread t1 = new Thread();
t1.start();
System. out.println(t1.getState());
try {
Thread. sleep(1000L);
} catch (InterruptedException e) {
}
System. out.println(t1.getState());
}