//沒(méi)有互斥鎖的情況（可以自己跑跑看運(yùn)行結(jié)果）：public class LockDemo { // private static Object lock = new Object();// static確保只有一把鎖  private int i = 0;  public void increaseI() {//   synchronized (lock) {      for(int k=0;k<10;k++) { // 對(duì)i執(zhí)行10次增1操作        i++;      }      System.out.println(Thread.currentThread().getName() + "線程，i現(xiàn)在的值：" + i);//   }  }  public static void main(String[] args) {    LockDemo ld = new LockDemo();    int threadNum = 1000;    // 選擇1000個(gè)線程讓結(jié)果更加容易觀測(cè)到    MyThread[] threads = new MyThread[threadNum];    for(int i=0;i<threads.length;i++) {      threads[i] = new MyThread(ld);      // 所有線程共用一個(gè)LockDemo對(duì)象      threads[i].start();    }  }}class MyThread extends Thread {  LockDemo ld;     public MyThread(LockDemo ld) {    this.ld = ld;  }  public void run() {    ld.increaseI();  }}//加上互斥鎖以后：public class LockDemo {  private static Object lock = new Object();  // static確保只有一把鎖  private int i = 0;  public void increaseI() {    synchronized (lock) {      for(int k=0;k<10;k++) {      // 對(duì)i執(zhí)行10次增1操作        i++;      }      System.out.println(Thread.currentThread().getName() + "線程，i現(xiàn)在的值：" + i);    }  }  public static void main(String[] args) {    LockDemo ld = new LockDemo();    int threadNum = 1000;    // 選擇1000個(gè)線程讓結(jié)果更加容易觀測(cè)到    MyThread[] threads = new MyThread[threadNum];    for(int i=0;i<threads.length;i++) {      threads[i] = new MyThread(ld);      // 所有線程共用一個(gè)LockDemo對(duì)象      threads[i].start();    }  }}class MyThread extends Thread {  LockDemo ld;  public MyThread(LockDemo ld) {    this.ld = ld;  }  public void run() {    ld.increaseI();  }}