java线程的run()没有返回值怎么办？

public void run() {}

run( ) 方法返回值是空, 怎么办?

解决方法：

• Note
• 使用 call() 方法
• Callable接口是 jdk 5 后新增的接口
• 例如：

  package com.example.thread;   import java.io.IOException; import java.io.InputStream; import java.net.HttpURLConnection; import java.net.MalformedURLException; import java.net.URL; import java.util.concurrent.Callable;   import android.util.Log;   import com.example.StreamTool.StreamTool;   public class MyThread1 implements Callable {   private static final String tag = "xxxyyy";   private String phone;   private String name;   public MyThread1(String name, String phone) {       this.name = name;     this.phone = phone;   }   // public MyThread1(String name, String phone) { //   super(name); //   this.phone = phone; //  }   //  public void run() { //   Log.i(tag, Thread.currentThread().getName() + "......start"); //   String newpath = "http://www.dianping.com/ajax/json/account/reg/mobile/send?m=" + phone + "&flow=t&callback=DP._JSONPRequest._5"; //   StringBuilder strBui = new StringBuilder(newpath); // //   try { //     URL url = new URL(strBui.toString()); //     HttpURLConnection con = (HttpURLConnection) url.openConnection(); //     con.addRequestProperty("Content-Type", "text/html; charset=UTF-8"); //     con.addRequestProperty( //             "User-Agent", //             "Mozilla/5.0 (Windows NT 6.1) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/38.0.2125.104 Safari/537.36"); //     con.addRequestProperty("Cookie", "_hc.v=\"\\\"0ffcdf91-a4d6-4b08-8800-3d59d2e2fe45.1413899372\\\"\"; abtest=\"48,124\\|52,133\\|47,122\\|44,106\\|45,115\"; __utma=1.29319792.1412090870.1413609669.1413645970.5; __utmz=1.1413645970.5.2.utmcsr=t.dianping.com|utmccn=(referral)|utmcmd=referral|utmcct=/xian; _tr.u=7dhY0yFhd9rY065F; tc=17; cy=17; cye=xian; t_rct=2172824|2171729|6457678; PHOENIX_ID=0a01743f-1492e1321c8-46e6a; 13.t=17deda7d2a7d8e46d84bf12a74627b72; 13.ts=cd3bd6495620e2a204912c4bdfd43220; thirdtoken=891671FC6B450418DD6E0611A3E4CF48; _hc.v=\"\\\"1bdad871-405e-46e3-97d6-46571ad48e14.1413897928\\\"\"; _tr.s=Zy1Ca2OAe1ptv06o; JSESSIONID=891671FC6B450418DD6E0611A3E4CF48"); //     con.addRequestProperty("Referer", "http://t.dianping.com/register"); //     con.setConnectTimeout(5000); //     con.setRequestMethod("GET"); //     //     if (con.getResponseCode() == 200){ //       InputStream inputStr = con.getInputStream(); //       String info = new String(StreamTool.read(inputStr), "UTF-8"); //       Log.i(tag, Thread.currentThread().getName() + info); //     } //   } catch (MalformedURLException e) { //     // TODO Auto-generated catch block //     e.printStackTrace(); //   } catch (IOException e) { //     // TODO Auto-generated catch block //     e.printStackTrace(); //   } catch (Exception e) { //     // TODO Auto-generated catch block //     e.printStackTrace(); //   } //   //    //  }     @Override   public String call() throws Exception {       Log.i(tag, Thread.currentThread().getName() + "......start");       String newpath = "http://www.dianping.com/ajax/json/account/reg/mobile/send?m=" + phone + "&flow=t&callback=DP._JSONPRequest._5";       StringBuilder strBui = new StringBuilder(newpath);         try {         URL url = new URL(strBui.toString());         HttpURLConnection con = (HttpURLConnection) url.openConnection();         con.addRequestProperty("Content-Type", "text/html; charset=UTF-8");         con.addRequestProperty(                 "User-Agent",                 "Mozilla/5.0 (Windows NT 6.1) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/38.0.2125.104 Safari/537.36");         con.addRequestProperty("Cookie", "_hc.v=\"\\\"0ffcdf91-a4d6-4b08-8800-3d59d2e2fe45.1413899372\\\"\"; abtest=\"48,124\\|52,133\\|47,122\\|44,106\\|45,115\"; __utma=1.29319792.1412090870.1413609669.1413645970.5; __utmz=1.1413645970.5.2.utmcsr=t.dianping.com|utmccn=(referral)|utmcmd=referral|utmcct=/xian; _tr.u=7dhY0yFhd9rY065F; tc=17; cy=17; cye=xian; t_rct=2172824|2171729|6457678; PHOENIX_ID=0a01743f-1492e1321c8-46e6a; 13.t=17deda7d2a7d8e46d84bf12a74627b72; 13.ts=cd3bd6495620e2a204912c4bdfd43220; thirdtoken=891671FC6B450418DD6E0611A3E4CF48; _hc.v=\"\\\"1bdad871-405e-46e3-97d6-46571ad48e14.1413897928\\\"\"; _tr.s=Zy1Ca2OAe1ptv06o; JSESSIONID=891671FC6B450418DD6E0611A3E4CF48");         con.addRequestProperty("Referer", "http://t.dianping.com/register");         con.setConnectTimeout(5000);         con.setRequestMethod("GET");           float x = 3.4f;         if (con.getResponseCode() == 200){           InputStream inputStr = con.getInputStream();           String info = new String(StreamTool.read(inputStr), "UTF-8");           Log.i(tag, Thread.currentThread().getName() + info);           if(info.contains("200"))             return "200";         }       } catch (MalformedURLException e) {         // TODO Auto-generated catch block         e.printStackTrace();       } catch (IOException e) {         // TODO Auto-generated catch block         e.printStackTrace();       } catch (Exception e) {         // TODO Auto-generated catch block         e.printStackTrace();       }         // TODO Auto-generated method stub     return "404";   }     }   如何处理返回值： ExecutorService exec = Executors.newCachedThreadPool();     ArrayList> results = new ArrayList>();     for(int i = 0; i < num; i++)       results.add(exec.submit(selectThread(telnumber)));     for (Future fs:results)       try {         if (fs.get().equals("200"))           success++;       } catch (InterruptedException e) {         // TODO Auto-generated catch block         e.printStackTrace();       } catch (ExecutionException e) {         // TODO Auto-generated catch block         e.printStackTrace();       }     return success;