当响应大小很大时，来自Android的HTTP POST不返回数据

Question

I have a problem when fire a POST request to server and after process server response result but when server write data sometime data can't transfer to client, dead at writer.write() function. I use Apache Tomcat to deploy app, each time server need response about 7m data before gzip and 300k after gzip

Please Help !

my code:

protected void dispatch(JSONObject request,
              Map<String, FormDataItem> formItems,
              HttpServletRequest servletRequest,
              HttpServletResponse servletResponse, SecurityToken token,
              String callback) throws JSONException, IOException {
        long timeGetData = 0;
        long begin = System.currentTimeMillis();

        String key = null;

        if (request.has("id")) {
              key = request.getString("id");
        }

        // getRpcHandler never returns null
        Future<?> future = getHandler(request, servletRequest).execute(
                    formItems, token, jsonConverter);

        timeGetData = System.currentTimeMillis();
        // Resolve each Future into a response.
        ResponseItem response = getResponseItem(future);
        ResponseItem responseTemp = (ResponseItem) response.getResponse();

        // Generate the output
        Writer writer = servletResponse.getWriter();

        if ("syndata.getAllDataFromServer".equals(request.getString("method"))) {
              if (responseTemp.getErrorCode() == 200) {
                    SynDataObject outObject = (SynDataObject) (responseTemp
                                .getResponse());
                    writer.write(jsonConverter.convertToString(outObject
                                .getParams()));
                    writer.write("\r\n");

                    for (int i = 0; i < outObject.getListTableData().size(); i++) {
                          TableDataObject subData = outObject.getListTableData().get(
                                      i);
                          int subDataLength = subData.getData().size();
                          int currentFarm = 0;
                          int factor = 1000;
                          int lastIndex = 0;

                          while (lastIndex < subDataLength) {
                                if ((currentFarm * factor + factor) > subDataLength) {
                                      lastIndex = (factor * currentFarm)
                                                  + (subDataLength - (factor * currentFarm));
                                } else {
                                      lastIndex = (factor * currentFarm) + factor;
                                }

                                TableDataObject chilData = new TableDataObject();
                                chilData.setTableName(subData.getTableName());
                                chilData.setTableColumns(subData.getTableColumns());
                                chilData.setPkField(subData.getPkField());

                                 chilData.setData(subData.getData().subList(
                                            currentFarm * factor, lastIndex));


                                writer.write(jsonConverter.convertToString(chilData));
                                writer.write("\r\n");
                                writer.flush();

                                ++currentFarm;
                          }
                    }
              } else {
                    Object result = getJSONResponse(key, response);
                    String content = jsonConverter.convertToString(result);

                    if (callback != null) {
                          writer.write(callback);
                          writer.write('(');
                    }

                    writer.write(content);

                    if (callback != null) {
                          writer.write(");\n");
                    }
              }
        } else {
              Object result = getJSONResponse(key, response);
              String content = jsonConverter.convertToString(result);

              if (callback != null) {
                    writer.write(callback);
                    writer.write('(');
              }

              writer.write(content);

              if (callback != null) {
                    writer.write(");\n");
              }
        }

  }

Answer 1

Each browser has some request timeout value. If the time taken to serve the request or the time taken to reach the writer.write() line exceeds, the client connection gets closed.

So u won't be able to write any info to writer.