程序功能描述：在页面上点击一个“Disable Account”按钮，后台实现Disable某个账号，程序原理如下：
- 首先在页面上点击按钮，该按钮的ID是“disableAccountBtn”，找出页面加载的JS文件，在文件中搜索出该ID，发现如下代码：
$('#disableAccountBtn').click(function() { $('#promptWinYes').unbind('click').click(function() { $('#promptWin').dialog('close'); $.getJSON(DISABLE_USER_ACTION, { uid : clientId }, function(data) { switchButtonVisible(false); showAlertWin('Warning', DISABLE_USER_CALLBACK_MSG); }); }); showPromptWin('Warning', DISABLE_USER_MSG); });其中$.getJSON来调用并获取远程的JSON字符串，将其转换为JSON对象，如果成功，则执行回调函数,再从JS中查找DISABLE_USER_ACTION="../disableUser.action. 可见这个调用最终执行了
../disableUser.action?uid=userID这个service - 查找后台JAVA代码，在UserManagementController.java中找到如下方法：
@RequestMapping("/disableUser.action") public ModelAndView disableUser(HttpServletRequest request) throws Exception { return WorkflowController.disableClient(request, clientAction); }此处用的是Spring MVC的框架，这个方法用到了clientAction
- 再进入WorkflowController.disableClient(request, clientAction)
public static ModelAndView disableClient(HttpServletRequest httpReq, ClientAction clientAction) { String clientId = httpReq.getParameter("uid"); UserBean sales = resolveSales(httpReq); String methodId = "{" + sales.getId() + "," + clientId + "," + System.currentTimeMillis() + "}"; logger.info("/disableUser.action BEGIN " + methodId); boolean success = true; String errorMsg = null; try { clientAction.disableClient(clientId, sales); } catch (Throwable e) { logger.error("Failed to disable user " + methodId, e); success = false; errorMsg = "Server Internal Error. Please contact the system Admin."; } finally { logger.info("/disableUser.action END " + methodId); } ModelMap model = new ModelMap(); model.addAttribute("success", success); model.addAttribute("errorMsg", errorMsg); return new ModelAndView("results", model); }可见，这个service执行成功后，返回的字符串是{"errorMsg":null,"success":true} - 进入clientAction.disableClient(clientId, sales)方法，ClientAction里面有很多方法：
/** * Action to disable an existing client. * * @param clientId * @param currentUser * @throws Exception */ public void disableClient(String clientId, UserBean currentUser) throws Exception { umUserService.createESFDataIfMissing(clientId); UserProfile oldUser = umUserService.getUserProfile(clientId); disableClient(currentUser, oldUser); } - 再进入dsiableClient:
void disableClient(UserBean salesUserBean, UserProfile clientUserProfile) throws Exception { if (salesUserBean == null || clientUserProfile == null) { return; } String clientId = clientUserProfile.getUid(); String clientName = clientUserProfile.getDisplayName(); UserRequestEntity userEntity = new UserRequestEntity(); userEntity.setTitle(UMTConstants.USER_PROFILE_TITLE + "(Disable)"); userEntity.setClientId(clientId); userEntity.setClientName(clientName); userEntity.setSalesId(salesUserBean.getId()); userEntity.setSalesName(salesUserBean.getName()); //restore old user profile try { userEntity.setProfile(JsonUtil.write(clientUserProfile)); } catch (Exception e) { logger.error("Failed to encode user profile into JSON.", e); } umWorkflow.startDisableClientWorkflow(userEntity, UMTConstants.WF_DISABLE_CLIENT); } - 最后调用通用的startDisableClientWorkflow（）方法：
/** * Start the workflow to disable an existing client. * * @param userEntity the user profile provided by front-end, cannot be null */ public void startDisableClientWorkflow(UserRequestEntity userEntity, String workflowName) throws Exception { //1) save records into request tables UserRequestEntityHelper.validatePV(userEntity); UMRequestEntity umEntity = requestTracker.save(userEntity); Long requestId = umEntity.getId(); logger.info("Saved request entity of [disable] for {" + userEntity.getClientId() + "} as " + requestId); //2) update request status umEntity.setStatus(UMRequestEntity.Status.ESF_DISABLE); startWorkflow(requestId, workflowName, umEntity); }startWorkflow():/** * Start workflow for request. * * @param requestId * @param workflowName * @param umEntity * @throws Exception */ public void startWorkflow(Long requestId, String workflowName, UMRequestEntity umEntity) throws Exception { logger.info("Start workflow " + workflowName + " for request [" + requestId + "]"); //1) get workflow and start the process instance UMWorkflowBean workflowBean = workflowRepository.findUMWorkflowByName(workflowName); String processId = workflowService.startProcessInstance(workflowBean.getProcessName(), new HashMap<String, String>()); //2) update request status if (umEntity == null) { umEntity = new UMRequestEntity(); umEntity.setStatus(UserRequestEntity.Status.PROCESSING); umEntity.setStatusFlag(0); } umEntity.setId(requestId); umEntity.setWorkflowId(workflowBean.getWorkflowId()); umEntity.setProcessId(processId); requestTracker.update(umEntity); logger.info("Started workflow for request [" + requestId + "]"); //3) transit to first state Set<String> nextStates = workflowService.findActiveStates(processId); StateHandler nextStateHandler = null; for (String nextState : nextStates) { nextStateHandler = handlerRepository.getByState(nextState); if (nextStateHandler != null) { break; } } if (nextStateHandler != null) { nextStateHandler.execute(requestId); } } } - 找到WorkFlowService的实现类对应的方法：
/** * Start the process instance. * */ public String startProcessInstance(String processKey, Map<String, String> variables) { ProcessInstance processInstance = executionService.startProcessInstanceByKey(processKey, variables); return processInstance.getId(); }ExecutionService这个类属于JBPM，全称是Java Business Process Management，是一种基于J2EE的轻量级工作流管理系统。
总结：这类AJAX+Spring MVC的程序基本原理就是前台JS代码去调用后台的Service.测试的时候打开Fidder或者Firebug就能捕捉到具体的service已经传递的参数
接下去是真证的Disable逻辑：
- 在ESFServiceImpl里有一个disableUser（）方法：
public void disableUser(String operator, String userId) throws Exception { // Map<String, String> userESFAttrMap = queryUserESFInfo(userId); // if (userESFAttrMap == null) { // throw new Exception("Disable user error. Can not find user: " // + userId); // } // if (ESFConstans.STATUS_ENABLED.equals(userESFAttrMap // .get(ESFConstans.CLIENT_USERS_ATTR.STATUS))) { // changeUserStatus(operator, userId); // } Connection con = null; CallableStatement st = null; ResultSet rs = null; try { con = getConnection(); st = con.prepareCall(ESFConstans.CALL_DISABLE_USER); st.setString(1, userId); st.setString(2, operator); st.execute(); } catch (SQLException e) { throw e; } catch (Exception e) { throw e; } finally { closeAllDBResources(rs, st, con); } }其中使用CallableStatement调用了存储过程ESFConstans.CALL_DISABLE_USER：public static final String CALL_DISABLE_USER = "call " + schema + "cdc_rules_gmo_serve." + profix + "set_status_v2(?,0,?)";