java.net.MalformedURLException java.net.URL。 <init>（未知來源）

Question

我不斷收到這個錯誤，我真的不知道爲什麼。我嘗試過不同的網址，但我仍然遇到同樣的錯誤。

java.net.MalformedURLException 的java.net.URL。（來源不明）

public class ProxyServlet extends HttpServlet { 

private String PostUrl = "http://localhost:8080/myProxy/myServlet"; 

private static final long serialVersionUID = 1L; 

public ProxyServlet() { 
    super(); 
    } 

protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { 

    System.out.println("Parameters retreived..."); 
    // map parameters to properties in config file and set response 
    Map(); 
    } 

private void Map() throws IOException{ 


     String urlParameters = "topic="+topic+"&item="+item+"&period="+period+"; 
     URL url = new URL(PostUrl); 
     HttpURLConnection conn = (HttpURLConnection)url.openConnection(); 
     System.out.println("Connection made to " + PostUrl); 
     conn.setDoOutput(true); 
     conn.setInstanceFollowRedirects(true); 
     conn.setRequestMethod("POST"); 
     conn.setRequestProperty("Content-Type", "application/x-www-form-urlencoded"); 
     conn.setRequestProperty("charset", "utf-8"); 

     OutputStream out = null; 

     try{ 
      System.out.println("Writing data to output stream..."); 
      out = conn.getOutputStream(); 
      out.write(urlParameters.getBytes()); 
      out.close(); 
      System.out.println("All done!!!"); 
     } 

     catch(IOException e){ 
      e.printStackTrace(); 
     } 
    } 
} 

任何幫助，將不勝感激！

謝謝！

Answer 1

此代碼不能編譯。

您的網址無效。由於上述原因，不能認爲它如上所示。

此外，您還必須URLEncode參數名稱和值。