Android开发中经常需要调用线程访问网络，而手机的网络信号经常断断续续，容易出现网络超时的情况，这种情况下后台线程往往得不到关闭，浪费系统资源。
在下面的例子中使用了java 中的Timer类，对线程进行了约束，如果线程在一定时间内为响应则终止该线程。
package com.zf.thread_test;import java.util.Timer;import java.util.TimerTask;import android.os.Bundle;import android.os.Handler;import android.os.Message;import android.app.Activity;import android.app.ProgressDialog;import android.util.Log;import android.view.View;import android.view.View.OnClickListener;import android.widget.Button;import android.widget.Toast;public class MainActivity extends Activity { private static final int TIME_OUT = 0; private static final int SUCCESS = 1; // 超时的时限为5秒 private static final int TIME_LIMIT = 5000; ProgressDialog proDialog; Timer timer; Thread thread; Button btn1, btn2; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); btn1 = (Button) findViewById(R.id.button1); btn2 = (Button) findViewById(R.id.button2); // 测试未超时的线程，为btn1绑定事件 btn1.setOnClickListener(new OnClickListener() { @Override public void onClick(View v) { proDialog = ProgressDialog.show(MainActivity.this, "提示", "线程运行中"); // 匿名内部线程 thread = new Thread() { @Override public void run() { while (true) { try { //线程休眠时间，超时 sleep(10000); } catch (InterruptedException e) { break; } } } }; thread.start(); // 设定定时器 timer = new Timer(); timer.schedule(new TimerTask() { @Override public void run() { sendTimeOutMsg(); } }, TIME_LIMIT); } }); // 测试超时的线程,为btn2绑定事件 btn2.setOnClickListener(new OnClickListener() { @Override public void onClick(View v) { proDialog = ProgressDialog.show(MainActivity.this, "提示", "线程运行中"); // 匿名内部线程 thread = new Thread() { public void run() { try { // 线程休眠时间，未超时 Thread.sleep(3000); } catch (InterruptedException e) { e.printStackTrace(); } Message msgSuc = new Message(); msgSuc.what = SUCCESS; myHandler.sendMessage(msgSuc); } }; thread.start(); // 设定定时器 timer = new Timer(); timer.schedule(new TimerTask() { @Override public void run() { sendTimeOutMsg(); } }, TIME_LIMIT); } }); } // 接收消息的Handler final Handler myHandler = new Handler() { public void handleMessage(android.os.Message msg) { switch (msg.what) { case TIME_OUT: //打断线程 thread.interrupt(); proDialog.dismiss(); Toast.makeText(MainActivity.this, "线程超时", Toast.LENGTH_SHORT) .show(); break; case SUCCESS: //取消定时器 timer.cancel(); proDialog.dismiss(); Toast.makeText(MainActivity.this, "线程运行完成", Toast.LENGTH_SHORT) .show(); break; default: break; } }; }; //向handler发送超时信息 private void sendTimeOutMsg() { Message timeOutMsg = new Message(); timeOutMsg.what = TIME_OUT; myHandler.sendMessage(timeOutMsg); }}