apache的HttpClient 执行总是错误，

apache的HttpClient 执行总是异常，求助啊！
HttpClient httpClient = new DefaultHttpClient(); 
HttpGet httpGet = new HttpGet("http://www.baidu.com/");
  try{
  HttpResponse response = httpClient.execute(httpGet);
  }
  catch(Exception e){
  System.out.println("<-------Exception------->");
  e.printStackTrace();
  }

执行到红色那句话时出异常，走到catch下面去了。异常如下：
08-22 14:25:22.784: W/System.err(8976): android.os.NetworkOnMainThreadException
08-22 14:25:22.784: W/System.err(8976): at android.os.StrictMode$AndroidBlockGuardPolicy.onNetwork(StrictMode.java:1099)
08-22 14:25:22.784: W/System.err(8976): at java.net.InetAddress.lookupHostByName(InetAddress.java:391)
08-22 14:25:22.784: W/System.err(8976): at java.net.InetAddress.getAllByNameImpl(InetAddress.java:242)
08-22 14:25:22.784: W/System.err(8976): at java.net.InetAddress.getAllByName(InetAddress.java:220)
08-22 14:25:22.784: W/System.err(8976): at org.apache.http.impl.conn.DefaultClientConnectionOperator.openConnection(DefaultClientConnectionOperator.java:137)
08-22 14:25:22.784: W/System.err(8976): at org.apache.http.impl.conn.AbstractPoolEntry.open(AbstractPoolEntry.java:164)
08-22 14:25:22.784: W/System.err(8976): at org.apache.http.impl.conn.AbstractPooledConnAdapter.open(AbstractPooledConnAdapter.java:119)
08-22 14:25:22.784: W/System.err(8976): at org.apache.http.impl.client.DefaultRequestDirector.execute(DefaultRequestDirector.java:360)

对HTTP这块不是很熟，我查阅了很多资料和书籍，代码都是这样写的，也有在网络上问过类似的问题，但是都没有一个好的解答，求高手点拨，谢谢~！


------解决方案--------------------
NetworkOnMainThreadException
提示你不要在主线程中访问网络。

把要访问的网络单独放在一个线程中：

Java code

new Thread(){
    @Override
    public void run()
    {
        HttpClient httpClient = new DefaultHttpClient();  
        HttpGet httpGet = new HttpGet("http://www.baidu.com/");
        try
        {
            HttpResponse response = httpClient.execute(httpGet);
        }
        catch(Exception e)
        {
            System.out.println("<-------Exception------->");
            e.printStackTrace();
        }       
    }
}.start();

------解决方案--------------------
Android好像是从3.0还是4.0版本开始强制要求网络操作不能在主线程进行，像楼上一样，另开一个线程就OK了