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。

 1 package com.example.day10_03htmlsourceViewer;
 2
 3 import java.io.ByteArrayOutputStream;
 4 import java.io.InputStream;
 5 import java.net.HttpURLConnection;
 6 import java.net.URL;
 7 import android.app.Activity;
 8 import android.os.Bundle;
 9 import android.os.Handler;
10 import android.os.Message;
11 import android.view.View;
12 import android.widget.TextView;
13 import android.widget.Toast;
14
15 public class MainActivity extends Activity {
16     @Override
17     protected void onCreate(Bundle savedInstanceState) {
18         super.onCreate(savedInstanceState);
19         setContentView(R.layout.activity_main);
20     }
21
22     final static int MSG_DOWNLOAD_OK =1;
23     final static int MSG_DOWNLOAD_ERROR =2;
24
25     Handler handler = new Handler(){
26         @Override
27         public void handleMessage(Message msg) {
28             super.handleMessage(msg);
29
30             switch (msg.what) {
31             case MSG_DOWNLOAD_OK:
32                 TextView tv_html= (TextView) findViewById(R.id.tv_html);
33                 tv_html.setText((String)msg.obj);
34                 break;
35             case MSG_DOWNLOAD_ERROR:
36                 Toast.makeText(MainActivity.this, "下载源码失败", 1).show();
37                 break;
38             default:
39                 break;
40             }
41         }
42     };
43     public void gethtml(View v){
44         Thread thread = new Thread(){
45             public void run() {
46                  String path = "http://192.168.3.30:8080/index2.html";
47                  try {
48                     URL url = new URL(path);
49                     HttpURLConnection conn = (HttpURLConnection) url.openConnection();
50
51                     conn.setConnectTimeout(5000);
52                     conn.setReadTimeout(5000);
53                     conn.setRequestMethod("GET");
54                     conn.connect();
55
56                     if(conn.getResponseCode()==200)
57                     {
58                         InputStream is = conn.getInputStream();
59
60                         ByteArrayOutputStream baos = new ByteArrayOutputStream();
61                         byte[] b = new byte[1024];
62                         int len = 0;
63                         while((len=is.read(b))!=-1)
64                         {
65                             baos.write(b, 0, len);
66                         }
67                         is.close();
68                         baos.close();
69                         String htmlsource = new String(baos.toByteArray(),"GBK") ;
70                         Message msg= handler.obtainMessage();
71                         msg.what=MSG_DOWNLOAD_OK;
72                         msg.obj=htmlsource;
73                         handler.sendMessage(msg);
74                     }
75                     else {
76                         Message msg= handler.obtainMessage();
77                         msg.what=MSG_DOWNLOAD_ERROR;
78                         handler.sendMessage(msg);
79                     }
80                 } catch ( Exception e) {
81                     e.printStackTrace();
82                 }
83             }
84             ;
85         };
86         thread.start();
87     }
88 }

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

效果图：