httptransportagent.java

手机与服务器通过SyncML进行同步的客户端框架以及API

                //#endif
                Log.info("[sendMessage] requestURL: [" + requestURL +"]");
                c = (HttpConnection)Connector.open(requestURL,
                        Connector.READ_WRITE, true);

                //Request Configuration: Added ACCEPT ENCODING Parameter
                setConfig(c, request.length);

                writeRequest(c, request);

                Log.info("[sendMessage] message sent, waiting for response.");

                //Receive response on is Inputstream
                is = c.openInputStream();

                logHeaders(c);

                long len = c.getLength();
                Log.info("HttpResponse length: " + len);

                // Check http error
                int httpCode = c.getResponseCode();
                Log.info("[sendMessage] Http Code: " + httpCode);
                if (httpCode != c.HTTP_OK) {
                    throw new SyncException(SyncException.SERVER_ERROR,
                            "Http error: code=[" + httpCode + "] msg=["
                            + c.getResponseMessage() + "]");
                }

                responseDate = c.getHeaderField(PROP_DATE);
                Log.info("[sendMessage] Date from server: " + responseDate);

                contentType = c.getHeaderField(PROP_CONTENT_ENCODING);
                Log.info("[sendMessage] Encoding Response Type from server: " + contentType);

                if ((len == -1) && (responseDate == null) && (contentType == null)) {
                    Log.error("[sendMessage] Error in http response, not reading stream...");
                } else {
                    data = StreamReaderFactory.getStreamReader(contentType).readStream(is, (int)len);

                    Log.info("[sendMessage] Stream correctly processed.");
                    break;
                }
            } catch (ConnectionNotFoundException e) {
                String msg = "HttpTransportAgent: can't open connection -->"
                        + e.toString() ;
                os=null;
                Log.error(msg);
                throw new SyncException(SyncException.ACCESS_ERROR, msg);
            } catch (IOException e) {
                Log.error("[sendMessage] Attempt n." + (i+1) + " failed. Retrying...");
                Log.error("[sendMessage] " + e);
                e.printStackTrace();
                if (i == NUM_RETRY-1) {
                    String msg = "HttpTransportAgent: connection broken --> "
                            + e.toString() ;
                    Log.error(msg);
                    throw new SyncException(SyncException.ACCESS_ERROR, msg);
                }
            } catch (IllegalArgumentException e) {
                String msg = "HttpTransportAgent: invalid argument for connection --> "
                        + e.toString() ;
                Log.error(msg);
                throw new SyncException(SyncException.ACCESS_ERROR, msg);
            } finally {
                if (is != null) {
                    try {
                        is.close();
                        is=null;
                    } catch(IOException ioe){
                        ioe.printStackTrace();
                        Log.error("sendmessage: can't close input stream.");
                    }
                }
                if (os != null) {
                    try {
                        os.close();
                        os=null;
                    } catch(IOException ioe){
                        ioe.printStackTrace();
                        Log.error("sendmessage: can't close output stream.");
                    }
                }
                if (c != null) {
                    try {
                        c.close();
                        c=null;
                    } catch(IOException ioe){
                        ioe.printStackTrace();
                        Log.error("sendmessage: can't close connection.");
                    }
                }
            }
        }
        return data;
    }

    private void writeRequest(final HttpConnection c, final byte[] request) throws IOException {
        OutputStream os = null;
        os = c.openOutputStream();
        os.write(request);
        os.close();
        Log.info("[writeRequest] Request written.");
    }

    // ---------------------------------------------------------- Private methods

    /**
     * Add request properties for the configuration, profiles,
     * and locale of this system.
     * @param c current HttpConnection to receive user agent header
     */
    private void setConfig(HttpConnection c, int length) throws IOException {
        String ua = this.userAgent;

        String locale = System.getProperty(PROP_MICROEDITION_LOCALE);

        if (ua == null) {
            // Build the default user agent
            String conf = System.getProperty(PROP_MICROEDITION_CONFIGURATION);
            String prof = System.getProperty(PROP_MICROEDITION_PROFILES);

            ua = "Profile/" + prof + " Configuration/" + conf ;
        }

        c.setRequestMethod(HttpConnection.POST);
        c.setRequestProperty("Connection", "Close");
        c.setRequestProperty(PROP_CONTENT_TYPE, "application/vnd.syncml+xml");


        c.setRequestProperty(PROP_CONTENT_LENGTH, String.valueOf(length));

        if (length == 0) {

            Log.error("content length has been set to 0 !");

        }

        // workaround to avoid errors on server
        // the client user agent must not be sent with User-Agent header
        c.setRequestProperty(PROP_USER_AGENT, "Funambol Java Mail" );

        // we use Device-Agent for such an issue
        c.setRequestProperty(PROP_DEVICE_AGENT, ua );

        // If Set-Cookie header is set to empty value in http
        // server response, in Nokia S60 3ed. FP1 devices the Application crashes
        // It's due to a Symbian KVM bug.
        // A specific workaround has been implemented: the client sends a specific header
        // 'x-funambol-force-cookies' to force the server to set a 'Set-Cookie' header not empty.
        if (forceCookies) {
            c.setRequestProperty(PROP_FORCE_COOKIES, "true" );
        }

        //Set Encoding and accepted properties: inflater or Gzip input Stream
        if (enableCompression){
            c.setRequestProperty(PROP_ACCEPT_ENCODING, COMPRESSION_TYPE_GZIP);
            Log.debug("Encoding Response Required from Client: " + COMPRESSION_TYPE_GZIP);
        }

        if (this.sizeThreshold != 0) {
            c.setRequestProperty(PROP_SIZE_THRESHOLD,
                    String.valueOf(this.sizeThreshold));
        }

        if (locale != null) {
            c.setRequestProperty(PROP_CONTENT_LANGUAGE, locale);
        }
    }

    public void enableCompression(boolean enable) {
        this.enableCompression = enable;
    }

    public void setThreshold(int threshold) {
        this.sizeThreshold = threshold;
    }

    public void setRequestURL(String requestURL) {
        this.requestURL = requestURL;
    }

    /**
     * Returns the last response date, if available, or null.
     */
    public String getResponseDate() {
        return responseDate;
    }

  private void logHeaders(final HttpConnection c) throws IOException {

        // debug section for reading http response headers
        if (Log.getLogLevel() >= Log.INFO) {
            StringBuffer sbh = new StringBuffer();
            String tmp = "";
            for (int h = 0; h<12; h++) {
                tmp = c.getHeaderFieldKey(h);
                sbh.append("[").append(h).append("] - ").
                        append(tmp);
                if ((tmp!=null)&&(!tmp.equals(""))) {
                    sbh.append(": ").append(c.getHeaderField(tmp)).append("\n");
                } else {
                    sbh.append("\n");
                }
            }
            Log.info("header: \n" + sbh.toString());
        }
    }

}