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java實現多執行緒交替列印兩個數

本文例項為大家分享了java實現多執行緒交替列印兩個數的具體程式碼,供大家參考,具體內容如下

方法1、使用wait和notify

package com.thread;
 
public class T01 {
 
 public static void main(String[] args) {
 char[] char1 = "AAAAAA".toCharArray();
 char[] char2 = "BBBBBB".toCharArray();
 Object object = new Object();
 
 Thread thread1 = new Thread(() -> {
  synchronized(object){//使用notify和wait時,必須要選獲取到鎖
   for (int i = 0; i < char1.length; i++) {
   try {
    System.out.print(char1[i]);
    object.notify();
    object.wait();
   } catch (InterruptedException e) {
    e.printStackTrace();
   }
   }
   object.notify();//必須加上,否則程式無法結束,兩個執行緒總有一個最後是wait狀態,所以此處必須加
  }
  
 },"t1");
 
 
 Thread thread2 = new Thread( () -> {
  synchronized(object){
   for (int i = 0; i < char2.length; i++) {
   try {
    System.out.print(char2[i]);
    object.notify();
    object.wait();
   } catch (InterruptedException e) {
    e.printStackTrace();
   }
   }
   object.notify();
  }
 },"t2");
 
 thread1.start();
 thread2.start();
 
 }
}

方法2、使用LockSupport方法

package com.thread;
 
import java.util.concurrent.locks.LockSupport;
 
public class T02 {
 static Thread thread1 ;
 static Thread thread2 ;
 public static void main(String[] args) {
 char[] char1 = "AAAAAA".toCharArray();
 char[] char2 = "BBBBBB".toCharArray();
 
 thread1 = new Thread(() -> {
  for (int i = 0; i < char1.length; i++) {
   System.out.print(char1[i]);
   LockSupport.unpark(thread2);
   LockSupport.park();
  }
 },"t1");
 
  thread2 = new Thread(() -> {
  for (int i = 0; i < char2.length; i++) {
   LockSupport.park();
   System.out.print(char2[i]);
   LockSupport.unpark(thread1);
  }
 },"t2");
 
 thread1.start();
 thread2.start();
 
 }
 
 
}

方法3、使用CAS自旋鎖

package com.thread;
 
public class T03 {
 enum ReadEnum{
 T1,T2;
 }
 static volatile ReadEnum r = ReadEnum.T1;
 public static void main(String[] args) {
 char[] char1 = "AAAAAA".toCharArray();
 char[] char2 = "BBBBBB".toCharArray();
 Thread thread1 = new Thread(() ->{
  for (int i = 0; i < char1.length; i++) {
  while (r != ReadEnum.T1) {
  }
  System.out.print(char1[i]);
  r = ReadEnum.T2;
  }
 },"t1");
 
 
 Thread thread2 = new Thread(() ->{
  for (int i = 0; i < char2.length; i++) {
  while (r != ReadEnum.T2) {
  }
  System.out.print(char2[i]);
  r = ReadEnum.T1;
  }
 },"t2");
 
 thread1.start();
 thread2.start();
 
 
 }
}

方法4、使用Condition方法

package com.thread;
 
import java.util.concurrent.locks.Condition;
import java.util.concurrent.locks.ReentrantLock;
 
 
public class T04 {
 
 public static void main(String[] args) {
 char[] char1 = "AAAAAA".toCharArray();
 char[] char2 = "BBBBBB".toCharArray();
 
 ReentrantLock lock = new ReentrantLock();
 Condition condition1 = lock.newCondition();
 Condition condition2 = lock.newCondition();
 
 Thread thread1 = new Thread(() ->{
  try {
  lock.lock();
  for (int i = 0; i < char1.length; i++) {
   System.out.print(char1[i]);
   condition2.signal();//喚醒執行緒2執行
   condition1.await();//執行緒1等待
  }
  condition2.signal();
  }catch (Exception e) {
  e.printStackTrace();
  }finally{
  lock.unlock();
  }
 },"t1");
 
 Thread thread2 = new Thread(() ->{
  try {
  lock.lock();
  for (int i = 0; i < char2.length; i++) {
   System.out.print(char2[i]);
   condition1.signal();
   condition2.await();
  }
  condition1.signal();
  } catch (Exception e) {
  e.printStackTrace();
  }finally{
  lock.unlock();
  }
 
 },"t2");
 
 thread1.start();
 thread2.start();
 
 
 }
}

Condition與notify相比的好處是,Condition可以指定需要喚醒的執行緒,而notify是無法指定的,只能隨機喚醒一個或者全喚醒(notifyAll)

以上就是本文的全部內容,希望對大家的學習有所幫助,也希望大家多多支援我們。