java多线程之Lock线程同步

时间:2023-03-09 20:47:47
java多线程之Lock线程同步

1、线程同步:

package cn.itcast.heima2;

import java.util.concurrent.locks.Lock;
import java.util.concurrent.locks.ReentrantLock; public class LockTest { /**
* @param args
*/
public static void main(String[] args) {
new LockTest().init();
} private void init(){
final Outputer outputer = new Outputer();
new Thread(new Runnable(){
@Override
public void run() {
while(true){
try {
Thread.sleep(10);
} catch (InterruptedException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
outputer.output("zhangxiaoxiang");
} }
}).start(); new Thread(new Runnable(){
@Override
public void run() {
while(true){
try {
Thread.sleep(10);
} catch (InterruptedException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
outputer.output("lihuoming");
} }
}).start(); } static class Outputer{
Lock lock = new ReentrantLock();
public void output(String name){
int len = name.length();
lock.lock();
try{
for(int i=0;i<len;i++){
System.out.print(name.charAt(i));
}
System.out.println();
}finally{
lock.unlock();
}
}
}
}

2、ReentrantLock的Condition的await,signal的应用:

package cn.itcast.heima2;

import java.util.concurrent.locks.Condition;
import java.util.concurrent.locks.Lock;
import java.util.concurrent.locks.ReentrantLock; public class ThreeConditionCommunication { public static void main(String[] args) {
final Business business = new Business();
new Thread(new Runnable() {
@Override
public void run() {
for (int i = 1; i <= 50; i++) {
business.sub2(i);
}
}
}).start();
new Thread(new Runnable() {
@Override
public void run() {
for (int i = 1; i <= 50; i++) {
business.sub3(i);
}
}
}).start(); for (int i = 1; i <= 50; i++) {
business.main(i);
}
}
static class Business {
Lock lock = new ReentrantLock();
Condition condition1 = lock.newCondition();
Condition condition2 = lock.newCondition();
Condition condition3 = lock.newCondition();
private int shouldSub = 1; public void sub2(int i) {
lock.lock();
try {
while (shouldSub != 2) {
try {
condition2.await();
} catch (Exception e) {
e.printStackTrace();
}
}
for (int j = 1; j <= 10; j++) {
System.out.println("sub2 thread sequence of " + j
+ ",loop of " + i);
}
shouldSub = 3;
condition3.signal();
} finally {
lock.unlock();
}
} public void sub3(int i) {
lock.lock();
try {
while (shouldSub != 3) {
try {
condition3.await();
} catch (Exception e) {
e.printStackTrace();
}
}
for (int j = 1; j <= 20; j++) {
System.out.println("sub3 thread sequence of " + j
+ ",loop of " + i);
}
shouldSub = 1;
condition1.signal();
} finally {
lock.unlock();
}
} public void main(int i) {
lock.lock();
try {
while (shouldSub != 1) {
try {
condition1.await();
} catch (Exception e) {
e.printStackTrace();
}
}
for (int j = 1; j <= 100; j++) {
System.out.println("main thread sequence of " + j
+ ",loop of " + i);
}
shouldSub = 2;
condition2.signal();
} finally {
lock.unlock();
}
} }
}