J2ME，Nokia，HttpConnection

Question

此代碼在SonyEricsson和Motorola手機上正常工作，但在諾基亞上，它或者在beginnig上未能完成任何請求或返回空響應，具體取決於型號。

HttpConnection hc = null; 
    InputStream is = null; 
    InputStreamReader isr = null; 
    String result = ""; 

    try 
    { 
     hc = (HttpConnection) Connector.open(url); 
     int rc = hc.getResponseCode(); 
     if (rc != HttpConnection.HTTP_OK) 
     { 
      throw new IOException(hc.getResponseMessage()); 
     } 

     is = hc.openInputStream(); 
     isr = new InputStreamReader(is, "utf-8"); 
     int ch; 
     while ((ch = is.read()) != -1) 
     { 
      result += (char) ch; 
     } 
    } 
    finally 
    { 
     if (is != null) 
     { 
      is.close(); 
     } 
     if (hc != null) 
     { 
      hc.close(); 
     } 
    } 

    return result; 

嘗試了不同的代碼與字節緩衝區，流等，結果總是相同的。有什麼問題？

Answer 1

嘗試

import java.io.ByteArrayOutputStream; 
import java.io.DataOutputStream; 
import java.io.IOException; 
import java.io.InputStream; 
import java.util.Enumeration; 
import java.util.Hashtable; 
import javax.microedition.io.Connector; 
import javax.microedition.io.HttpConnection; 

public class Transport { 

public static int BUFFER_LENGTH = 100;//1024; 
public static boolean USE_FLUSH = false; 

static { 
    if (DeviceDetect.getDeivice() == DeviceDetect.SAMSUNG) { 
     BUFFER_LENGTH = 1024; 
     USE_FLUSH = true; 
    } 
} 
public static String SESSION_COOKIE = null; 


private static int rnd = 1; 

private static final String request(String url, String method, Hashtable params) throws IOException { 
    HttpConnection conn = null; 
    DataOutputStream dos = null; 
    InputStream in = null; 

    try { 

     String encodedParams = null; 
     if (params != null && params.size() > 0) { 
      encodedParams = getEncodedParams(params); 
     } 
     if (method == null) { 
      if (encodedParams.length() < 2000) { 
       method = "GET"; 
      } else { 
       method = "POST"; 
      } 
     } 

     method = method != null && method.equalsIgnoreCase("POST") ? HttpConnection.POST : HttpConnection.GET; 

     if (method.equalsIgnoreCase(HttpConnection.GET)) { 
      if (encodedParams != null) { 
       url += (url.indexOf("?") == -1 ? "?" : "&") + encodedParams; 
       encodedParams = null; 
      } 
      url += (url.indexOf("?") == -1 ? "?" : "&") + "_rnd=" + rnd++; 
     } 

     conn = (HttpConnection) Connector.open(url, Connector.READ_WRITE, true); 
     if (conn == null) { 
      throw new IOException("HttpConnection is null, please check Access Point configuration"); 
     } 

     conn.setRequestMethod(method); 
     conn.setRequestProperty("User-Agent", UserAgent.getUserAgent()); 
     conn.setRequestProperty("Content-Type", "application/x-www-form-urlencoded"); 
     if (SESSION_COOKIE != null) { 
      conn.setRequestProperty("Cookie", SESSION_COOKIE); 
     } 

     byte[] buff = new byte[BUFFER_LENGTH]; 
     if (encodedParams != null) { 
      byte[] bytes = encodedParams.getBytes("UTF-8"); 
      String lengthStr = bytes.length + ""; 
      conn.setRequestProperty("Content-Length", lengthStr); 

      dos = conn.openDataOutputStream(); 
      if (dos == null) { 
       throw new IOException("OutputStream is null, please check Access Point configuration"); 
      } 

      for (int i = 0, l = bytes.length; i < l; i += Transport.BUFFER_LENGTH) { 
       if (Transport.BUFFER_LENGTH == 1) { 
        dos.writeByte(bytes[i]); 
       } else { 
        int count = Math.min(Transport.BUFFER_LENGTH, l - i); 
        System.arraycopy(bytes, i, buff, 0, count); 
        dos.write(buff, 0, count); 
       } 
       if (Transport.USE_FLUSH) { 
        dos.flush(); 
       } 
      } 

      dos.flush(); 
      try { 
       dos.close(); 
      } catch (IOException ex) { 
      } 
     } 

     String setCookie = conn.getHeaderField("Set-Cookie"); 
     if (setCookie != null) { 
      int ind1 = setCookie.indexOf("JSESSIONID="); 
      if (ind1 > -1) { 
       int ind2 = setCookie.indexOf(";", ind1); 
       SESSION_COOKIE = ind2 == -1 ? setCookie.substring(ind1) : setCookie.substring(ind1, ind2 + 1); 
      } 
     } 

     in = conn.openInputStream(); 
     if (in == null) { 
      throw new IOException("InputStream is null, please check Access Point configuration"); 
     } 
     ByteArrayOutputStream baos = new ByteArrayOutputStream(); 
     int n = in.read(buff); 
     while (n > -1) { 
      baos.write(buff, 0, n); 
      n = in.read(buff); 
     } 
     baos.flush(); 
     baos.close(); 
     String response = new String(baos.toByteArray(), "UTF-8"); 
     try { 
      in.close(); 
     } catch (Exception ex) { 
     } 
     try { 
      conn.close(); 
     } catch (Exception ex) { 
     } 

     return response; 
    } finally { 
     try { 
      dos.close(); 
     } catch (Exception ex) { 
     } 
     try { 
      in.close(); 
     } catch (Exception ex) { 
     } 
     try { 
      conn.close(); 
     } catch (Exception ex) { 
     } 
    } 

} 

public static String getEncodedParams(Hashtable params) throws IOException { 
    String str = ""; 
    Enumeration keys = params.keys(); 
    while (keys.hasMoreElements()) { 
     String name = (String) keys.nextElement(); 
     Object value = params.get(name); 
     if (value == null || name == null) { 
      continue; 
     }    
     str += "&" + URLEncoder.encode(name.toString(), "UTF-8") + "=" + URLEncoder.encode(value.toString(), "UTF-8"); 
    } 
    if (str.length() > 1) { 
     str = str.substring(1); 
    } 
    return str; 
} 
} 

Answer 2

我不知道這是否會爲你工作，但我也有類似的問題，發現指定端口號使工作（在一些比較老的諾基亞機型）。即轉換：

http://www.mysite.com/my_page.html 

到：

http://mysite.com:80/my_page.html