一個死結的簡單例子

public class DeadLock {
 public static void main(String[] args) {
  // 2個資源
  final Object resource1 = "resource1";
  final Object resource2 = "resource2";
  // 第一個線程，想先佔有resource1，再嘗試著佔有resource2
  Thread t1 = new Thread() {
   public void run() {
    //嘗試佔有了resource1
    synchronized (resource1) {
     //成功佔有resource1
     System.out.println("Thread 1: locked resource 1");
     //休眠一段時間
     try {
      Thread.sleep(50);
     } catch (InterruptedException e) {
     }
     // 嘗試著佔有resource2，如果不能佔有，該線程會一直等待
     synchronized (resource2) {
      System.out.println("Thread 1: locked resource 2");
     }
    }
   }
  };

  // 第二個線程，想先佔有resource2，再佔有resource1
  Thread t2 = new Thread() {
   public void run() {
    // 嘗試著佔有resource2
    synchronized (resource2) {
     // 成功佔有resource2
     System.out.println("Thread 2: locked resource 2");
     // 休眠一段時間
     try {
      Thread.sleep(50);
     } catch (InterruptedException e) {
     }
     // 嘗試佔有resource1，如果不能佔有，該線程會一直等待
     synchronized (resource1) {
      System.out.println("Thread 2: locked resource 1");
     }
    }
   }
  };
  // 啟動兩個線程
  t1.start();
  t2.start();
 }
}