010_03HTML源码查看器

    主要用到了ByteArrayOutputStream类。该类无需指定输出流的路径，而是将数据直接输出到内存缓冲区。

使用toByteArray方法获取内存缓冲区数据。

package com.example.day10_03htmlsourceViewer;

import java.io.ByteArrayOutputStream;
import java.io.InputStream;
import java.net.HttpURLConnection;
import java.net.URL;
import android.app.Activity;
import android.os.Bundle;
import android.os.Handler;
import android.os.Message;
import android.view.View;
import android.widget.TextView;
import android.widget.Toast;

public class MainActivity extends Activity {
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
    }
 
    final static int MSG_DOWNLOAD_OK =1; 
    final static int MSG_DOWNLOAD_ERROR =2; 
    
    Handler handler = new Handler(){
        @Override
        public void handleMessage(Message msg) {
            super.handleMessage(msg);
            
            switch (msg.what) {
            case MSG_DOWNLOAD_OK:
                TextView tv_html= (TextView) findViewById(R.id.tv_html);
                tv_html.setText((String)msg.obj);                
                break;
            case MSG_DOWNLOAD_ERROR:
                Toast.makeText(MainActivity.this, "下载源码失败", 1).show();
                break;
            default:
                break;
            }
        }        
    };
    public void gethtml(View v){
        Thread thread = new Thread(){    
            public void run() {
                 String path = "http://192.168.3.30:8080/index2.html";
                 try {
                    URL url = new URL(path);
                    HttpURLConnection conn = (HttpURLConnection) url.openConnection();
                    
                    conn.setConnectTimeout(5000);
                    conn.setReadTimeout(5000);
                    conn.setRequestMethod("GET");                   
                    conn.connect();
                    
                    if(conn.getResponseCode()==200)
                    {
                        InputStream is = conn.getInputStream();

                        ByteArrayOutputStream baos = new ByteArrayOutputStream();
                        byte[] b = new byte[1024];
                        int len = 0;
                        while((len=is.read(b))!=-1)
                        {
                            baos.write(b, 0, len);
                        }
                        is.close();
                        baos.close();                                      
                        String htmlsource = new String(baos.toByteArray(),"GBK") ;                       
                        Message msg= handler.obtainMessage();
                        msg.what=MSG_DOWNLOAD_OK;
                        msg.obj=htmlsource;
                        handler.sendMessage(msg);                        
                    }
                    else {                       
                        Message msg= handler.obtainMessage();
                        msg.what=MSG_DOWNLOAD_ERROR;                       
                        handler.sendMessage(msg);                        
                    }                                                                   
                } catch ( Exception e) {
                    e.printStackTrace();
                }    
            }
            ;
        };
        thread.start();    
    }
}

activity_main.xml和AndroidManifest.xml与010_02带缓存的图片查看器相同。

效果图：