exception - IOException：未连接类：黑莓中的类 net.rim.device.api.io.ConnectionClosedException

Question

我从我的黑莓 java 代码中获取 net.rim.device.api.io.ConnectionClosedException。下面代码中突出显示的是引发异常的行。

hc = (HttpConnection) Connector.open(url);  

        hc.setRequestProperty("Content-Type", "multipart/form-data; boundary=" + getBoundaryString());

        hc.setRequestMethod(HttpConnection.POST);           

        hc.setRequestProperty(HttpProtocolConstants.HEADER_ACCEPT_CHARSET,
                "ISO-8859-1,utf-8;q=0.7,*;q=0.7");

        hc.setRequestProperty(HttpProtocolConstants.HEADER_CONTENT_LENGTH ,Integer.toString(fileBytes.length));

        OutputStream dout = hc.openOutputStream();

        dout.write(boundaryMessage.getBytes());
        dout.write(this.postBytes);
        dout.write(endBoundary.getBytes());             

        dout.close();

        int ch;     

        **is = hc.openInputStream();** //exception raised here

        if(hc.getResponseCode()== HttpConnection.HTTP_OK)
        {                       
            while ((ch = is.read()) != -1)
            {
                bos.write(ch);
            }
            res = bos.toByteArray();
            System.out.println("res loaded..");             
        }
        else {              
            System.out.println("Unexpected response code: " + hc.getResponseCode());            
            hc.close();
            return null;
        }             
    }
    catch(IOException e)
    {           
        System.out.println("====IOException : "+e.getMessage()+" Class: "+e.getClass());                
    }
    catch(Exception e1)
        {
            //e1.printStackTrace();                 
            System.out.println("====Exception : "+e1.getMessage()+" Class: "+e1.getClass());    
        }
    finally
    {
        try
        {
            if(bos != null)
                bos.close();

            if(is != null)
                is.close();

            if(hc != null)
                hc.close();
        }
        catch(Exception e2)
        {
            e2.printStackTrace();               
            System.out.println("====Exception : "+e2.getMessage()); 
        }
    }

我应该怎么做才能纠正这个？有人可以帮忙吗？提前致谢。