AsyncTask - HttpURLConnection 联网加载工具类

package com.example.abnerming.httputil.net;

import android.os.AsyncTask;

import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.PrintWriter;
import java.net.HttpURLConnection;
import java.net.MalformedURLException;
import java.net.URL;

/**
* 使用AyncTask来实现异步
* */
public class HelperAsnc {
public HelperAsnc(){}

//get请求
public HelperAsnc get(String url){
    doHttp(url,"GET","");
    return this;
}

//联网请求
private void doHttp(String url,String method,String string){
    myAsyncTask=new MyAsyncTask(url,method,string);
    myAsyncTask.execute();
}

//post请求
public HelperAsnc post(String url,String string){
    doHttp(url,"POST",string);
    return this;
}

private MyAsyncTask myAsyncTask;

private class MyAsyncTask extends AsyncTask<String,Integer,String>{
    private String url,method,string;
    public MyAsyncTask(String url,String method,String string){
        this.url=url;
        this.method=method;
        this.string=string;
    }
    //在子线程里运行
    @Override
    protected String doInBackground(String... strings) {
        String message="";
        try {
            URL mUrl=new URL(url);
           HttpURLConnection connection= (HttpURLConnection) mUrl.openConnection();
           connection.setRequestMethod(method);
           connection.setConnectTimeout(5000);

           if("POST".equals(method)){
               PrintWriter printWriter=new PrintWriter(connection.getOutputStream());
               printWriter.write(string);
               printWriter.flush();
               printWriter.close();
           }
           connection.connect();

           int code=connection.getResponseCode();
           if(code==HttpURLConnection.HTTP_OK){
               InputStream inputStream=connection.getInputStream();
               String data=convertStream2String(inputStream);
               message=data;
           }else{
               message="0";
           }
        } catch (MalformedURLException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }
        return message;
    }

    //在主线程里设置方法
    @Override
    protected void onPostExecute(String s) {
        super.onPostExecute(s);
        if("0".equals(s)){//失败
            listener.fail();
        }else{
            listener.success(s);
        }

    }
}

//流转字符串
private   String convertStream2String(InputStream input){
    ByteArrayOutputStream baos = new ByteArrayOutputStream();// 自带缓存的输出流
    int len=-1;
    byte [] buffer = new byte[512];
    try {
        while((len = input.read(buffer))!=-1){
            baos.write(buffer, 0, len); // 将读到的字节，写入baos
        }
        return new String(baos.toByteArray());
    } catch (IOException e) {
        e.printStackTrace();
    }
    return null;
}

private HttpListener listener;

//传递接口
public void result(HttpListener listener){
    this.listener=listener;
}

public interface HttpListener{
    void success(String data);
    void fail();
}

}