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package learning_java.Exercise;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.locks.Condition;
import java.util.concurrent.locks.Lock;
import java.util.concurrent.locks.ReentrantLock;
public class MultiThreadPrinter {
public static void main(String[] args) {
int gap = 3;
int end = 100;
ExecutorService executor = Executors.newFixedThreadPool(gap);
for (int i = 0;
i < gap;
i ++) {
executor.execute(new PrinterWithLock(i, gap, end));
}
executor.shutdown();
}private static class Printer implements Runnable{
private static final Object LOCK = new Object();
private int threadID;
private final int GAP;
private static int count = 0;
private Printer(int id, int gap) {
threadID = id;
GAP = gap;
}@Override
public void run() {
while (true) {
synchronized (LOCK) {
while (count % GAP != this.threadID) {
if (count >= 101) break;
try {
LOCK.wait();
} catch (InterruptedException ex) {
ex.printStackTrace();
}
}
if (count >= 101) break;
System.out.println("ThreadID:\t" + threadID + "\t:\t" + count);
++count;
LOCK.notifyAll();
}
}
}
}private static class PrinterWithLock implements Runnable {
// 需要注意，这里需要都为private static
private static Lock lock = new ReentrantLock();
// Condition若不是static的，则无法传递消息
private static Condition isCurrentID = lock.newCondition();
private final int threadID;
private final int GAP;
private static int count = 0;
private final int END;
private PrinterWithLock(int id, int gap, int end) {
threadID = id;
GAP = gap;
END = end;
}@Override
public void run() {
while (true) {
try {
lock.lock();
while (count % GAP != threadID) {
if (count > END) break;
isCurrentID.await();
}
if (count > END) break;
System.out.println("ThreadID:\t" + threadID + "\t:\t" + count);
++count;
isCurrentID.signalAll();
} catch (InterruptedException ex) {
ex.printStackTrace();
} finally {
lock.unlock();
}
}
}//@Override
//public void run() {
//while (true) {
//try {
//lock.lock();
//while (count % 3 != this.threadID) {
//if (count >= 101) {
//break;
//}
//try {
//isCurrentID.await();
//} catch (InterruptedException e) {
//e.printStackTrace();
//}
//}
//
//if (count >= 101) {
//break;
//}
//System.out.println("thread-" + this.threadID + ":" + count);
//count++;
//
//isCurrentID.signalAll();
//
//} finally {
//lock.unlock();
//}
//}
//}
}private static class PrintThread2 implements Runnable {
private static final ReentrantLock lock = new ReentrantLock();
private static final Condition c = lock.newCondition();
private static int count = 0;
//作为计数，同时也作为资源；因为这道题目是自然数作为资源，所以正好可以公用；
private Integer threadNo;
public PrintThread2(Integer threadNo) {
this.threadNo = threadNo;
}@Override
public void run() {
while (true) {
try {
lock.lock();
while (count % 3 != this.threadNo) {
if (count >= 101) {
break;
}
try {
c.await();
} catch (InterruptedException e) {
e.printStackTrace();
}
}if (count >= 101) {
break;
}
System.out.println("thread-" + this.threadNo + ":" + count);
count++;
c.signalAll();
} finally {
lock.unlock();
}
}
}
}
}
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