java 顺序输出_java多线程顺序输出ABCD

package huawei;

import java.util.concurrent.locks.Lock;

import java.util.concurrent.locks.ReentrantLock;/***/

public classDemo extends Thread{private staticString tmp ;private static Lock lock = newReentrantLock();private static int state =0;staticboolean flag;public static String multiThreadWrite(final inttimes) {

tmp=newString();

flag=false;

Thread threadA=newThread()

{public voidrun(){int count =0;while(count

{lock.lock();if(state%4==0)

{

tmp+= "A";

state++;

count++;

}lock.unlock();

}

}

};

Thread threadB=newThread()

{public voidrun(){int count =0;while(count

{lock.lock();if(state%4==1)

{

tmp+= "B";

state++;

count++;

}lock.unlock();

}

}

};

Thread threadC=newThread()

{public voidrun(){int count=0;while(count

{lock.lock();if(state%4==2)

{

tmp+= "C";

state++;

count++;

}lock.unlock();

}

}

};

Thread threadD=newThread()

{public voidrun()

{int count =0;while(count

{lock.lock();if(state%4==3)

{

tmp+= "D";

state++;

count++;

}lock.unlock();

}

flag=true;

}

};

threadA.start();

threadB.start();

threadC.start();

threadD.start();while(!flag); //防止main线程在四个线程执行完之前就返回tmp值

returntmp;

}

}