锁内部使用多个Condition 一直不对... - 黑马程序员技术交流社区

import java.util.Random;
import java.util.concurrent.CountDownLatch;
import java.util.concurrent.locks.Condition;
import java.util.concurrent.locks.Lock;
import java.util.concurrent.locks.ReentrantLock;
public class ConditionDemo {
private final Lock lock = new ReentrantLock();
private final Condition isFull = lock.newCondition();
private final Condition isEmtry = lock.newCondition();
private String[] data = new String[10];
private int len, getStr,putStr;
private StringBuilder buff = new StringBuilder();
public void putData(){
lock.lock();
System.out.println("正在填充数据...");
try{
while(len==data.length){
System.out.println(Thread.currentThread().getName()+" 填充完毕..."); // 这里无法打印
putStr=buff.length();
try{
isFull.await();
}catch(InterruptedException e){
System.err.println(e.toString());
}
}
while(putStr<=data.length){
if(putStr==data.length){
putStr = 0;
break;
}
data[putStr] = String.valueOf(new Random().nextInt(100));
System.out.println("data["+putStr+"]="+data[putStr]);
++putStr;
++len;
}
isEmtry.signal();
}finally{
lock.unlock();
}
}
public void getData(){
lock.lock();
System.out.println("正在截获信息..."); // 运行到这里，卡住了
try{
while(len==0){
System.out.println(Thread.currentThread().getName()+"截获数据完毕...");
System.out.println(buff.toString());
try {
isEmtry.await();
} catch (InterruptedException e) {
e.printStackTrace();
}
}
while(getStr<=data.length){
if(getStr==data.length){
getStr = 0;
break;
}
String info = data[getStr];
buff.append(info+",");
++getStr;
--len;
}
isFull.signal();
}finally{
lock.unlock();
}
}
public static void main(String[] args) {
final ConditionDemo condition = new ConditionDemo();
final CountDownLatch latch = new CountDownLatch(1);
new Thread(new Runnable(){
@Override
public void run(){
condition.putData();
latch.countDown();
}
}).start();
try {
latch.await();
} catch (InterruptedException e) {
e.printStackTrace();
}
condition.getData();
}
}

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public void getData(){
lock.lock();
System.out.println("正在截获信息..."); // 运行到这里，卡住了
try{
while(len==0){ //因为没输出Thread.currentThread().getName()+"截获数据完毕..."，所以len应该是！=0吧，你改成while(len!=0)试试
System.out.println(Thread.currentThread().getName()+"截获数据完毕...");
System.out.println(buff.toString());
try {
isEmtry.await();
} catch (InterruptedException e) {
e.printStackTrace();
}
}

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