Http通信（HttpClient）

   HttpURLConnection是java.net.*包提供的类，但java JDK 库本身功能还不够丰富和灵活；

Apache HttpClient是一个开源项目，功能更加完善，弥补了java.net.*灵活性不足的缺点。

 

    使用HttpClient接口要加入httpclient-4.3.1.jar相关的jar包

private void getHttpClientConnection(String url){
final String getUrl = url;
new Thread(new Runnable() {//新建一个子线程
        String getUrl2 = getUrl;
@Override
public void run() {
            HttpClient hc = new DefaultHttpClient();//1.创建一个HttpClient,(DefaultHttpClient表示默认属性)
            HttpGet hg = new HttpGet(getUrl2);//2.HttpGet实例，通过GET方法
            InputStream in = null;
            StringBuffer sb = null;
try{
                HttpResponse hr = hc.execute(hg);//3.HttpResponse Http响应,HttpClient执行HttpGet方法
//连接成功
if ((hr.getStatusLine().getStatusCode()) == 200){//4.得到响应码，如果==200，连接成功
                    in = hr.getEntity().getContent();//5.获取返回的数据 InPutStream流获取响应得到的内容
                    BufferedReader br = new BufferedReader(new InputStreamReader(in));//BufferedReader读取数据流
char[] buf = new char[1024];
int longth = 0;
                    sb = new StringBuffer();
while((longth = br.read(buf)) != -1){//读取BufferedReader，放入StringBuffer
                        sb.append(buf,0,longth);
                    }

                }
            }catch(IOException e){
                e.printStackTrace();
            }finally{
if (in != null){
try {
                        in.close();
                    } catch (IOException e) {
                        e.printStackTrace();
                    }
                }
            }

            Message message = new Message();//新建Message
            message.what = CHANGE_TEXT;
            message.obj = sb.toString();//Message.obj得到StringBuffer的内容
handler.sendMessage(message);//sendMessage

        }
    }).start();
}

-----------------------------------------

类中建一个Handler接收message

private static final int CHANGE_TEXT = 1;

private Handler handler = new Handler(){
@Override
public void handleMessage(Message msg) {
super.handleMessage(msg);
if (msg.what == CHANGE_TEXT){
textView.setText(msg.obj.toString());
        }
    }
};