十六、从网络中获取网页数据

从网络中获取网页数据时，网页有可能使用GZIP压缩技术对页面进行压缩，这样就会减小通过网络传输的数据量，提高浏览的速度。因此在获取网络数据时要对其进行判断，对GZIP格式的数据使用GZIPInputStream对其特殊处理，否则在获取数据可能出现乱码哦.

                 

 以下为网络中获取网页数据的案例代码

 

  

   package
    com.ljq.test;


   import
    java.io.ByteArrayOutputStream;

   import
    java.io.InputStream;

   import
    java.net.HttpURLConnection;

   import
    java.net.URL;

   import
    java.util.zip.GZIPInputStream;

   import
    java.util.zip.GZIPOutputStream;


   /**
   
 * 从网络中获取网页数据
 * 
 * 
   @author
    jiqinlin
 *
 
   */
   

   public
    
   class
    InternetTest2 {

 @SuppressWarnings(
   "
   static-access
   "
   )
 
   public
    
   static
    
   void
    main(String[] args) 
   throws
    Exception {
 String result 
   =
    
   ""
   ;
 
   //
   URL url = new URL("
   http://www.sohu.com
   ");
   

    URL url 
   =
    
   new
    URL(
   "
   http://www.ku6.com/
   "
   );
 HttpURLConnection conn 
   =
    (HttpURLConnection) url.openConnection();
 conn.setConnectTimeout(
   6
   *
    
   1000
   );
   //
   设置连接超时
   

    
   if
    (conn.getResponseCode() 
   !=
    
   200
   ) 
   throw
    
   new
    RuntimeException(
   "
   请求url失败
   "
   );
 InputStream is 
   =
    conn.getInputStream();
   //
   得到网络返回的输入流
   

    
   if
   (
   "
   gzip
   "
   .equals(conn.getContentEncoding())){
 result 
   =
    
   new
    InternetTest2().readDataForZgip(is, 
   "
   GBK
   "
   );
 }
   else
    {
 result 
   =
    
   new
    InternetTest2().readData(is, 
   "
   GBK
   "
   );
 }
 conn.disconnect();
 System.out.println(result);
 System.err.println(
   "
   ContentEncoding: 
   "
    
   +
    conn.getContentEncoding());
 }
 
 
   //
   第一个参数为输入流,第二个参数为字符集编码
   

    
   public
    
   static
    String readData(InputStream inSream, String charsetName) 
   throws
    Exception{
 ByteArrayOutputStream outStream 
   =
    
   new
    ByteArrayOutputStream();
 
   byte
   [] buffer 
   =
    
   new
    
   byte
   [
   1024
   ];
 
   int
    len 
   =
    
   -
   1
   ;
 
   while
   ( (len 
   =
    inSream.read(buffer)) 
   !=
    
   -
   1
    ){
 outStream.write(buffer, 
   0
   , len);
 }
 
   byte
   [] data 
   =
    outStream.toByteArray();
 outStream.close();
 inSream.close();
 
   return
    
   new
    String(data, charsetName);
 }
 
 
   //
   第一个参数为输入流,第二个参数为字符集编码
   

    
   public
    
   static
    String readDataForZgip(InputStream inStream, String charsetName) 
   throws
    Exception{
 GZIPInputStream gzipStream 
   =
    
   new
    GZIPInputStream(inStream);
 ByteArrayOutputStream outStream 
   =
    
   new
    ByteArrayOutputStream();
 
   byte
   [] buffer 
   =
   new
    
   byte
   [
   1024
   ];
 
   int
    len 
   =
    
   -
   1
   ;
 
   while
    ((len 
   =
    gzipStream.read(buffer))
   !=-
   1
   ) {
 outStream.write(buffer, 
   0
   , len);
 }
 
   byte
   [] data 
   =
    outStream.toByteArray();
 outStream.close();
 gzipStream.close();
 inStream.close();
 
   return
    
   new
    String(data, charsetName);
 }

}