扩展Spring MVC 用以支持Controller对Ajax的处理

扩展Spring MVC 用以支持Controller对Ajax的处理


pring Mvc中没有特别针对于Ajax请求的处理Controller.但是AbstractController和 
SimpleFormController也是可以针对Ajax的请求给与相应的.但显得有一点点的不自然. 
Java代码 
@Override  
protected ModelAndView onSubmit(HttpServletRequest request, HttpServletResponse response, Object cmd,   
        BindException ex) {   
    String userId=request.getParamater("userId");   
                 Map userInfoMap=userDao.getUserBaseInfo(userId);   
                 JSONObject object = new JSONObject();   
                 object.put("userInfoMap",userInfoMap);   
    response.setContentType("text/Xml;charset=gbk");   
    PrintWriter out = null;   
    try {   
        out = response.getWriter();   
             out.println(object.toString());   
                
    }   
    catch (IOException ex1) {   
        ex1.printStackTrace();   
    }finally{   
                           out.close();   
                  }   
    return null;   
}  

        @Override
        protected ModelAndView onSubmit(HttpServletRequest request, HttpServletResponse response, Object cmd,
                        BindException ex) {
                String userId=request.getParamater("userId");
                  Map userInfoMap=userDao.getUserBaseInfo(userId);
                  JSONObject object = new JSONObject();
                  object.put("userInfoMap",userInfoMap);
                response.setContentType("text/Xml;charset=gbk");
                PrintWriter out = null;
                try {
                        out = response.getWriter();
                         out.println(object.toString());
                         
                }
                catch (IOException ex1) {
                        ex1.printStackTrace();
                }finally{
                            out.close();
                   }
                return null;
        }
说明一下我向客户端页面response的是一个JSon对象,选择JSon这种数据格式的两个原因是: 


体积小可降低流量. 
Js端解码十分方便,Js对JSon格式数据有原生的支持. 

使用Spring Mvc原有的SimpleFormController,从上边的例子上看是可以实现的,但是每次都要写"将JSonObject写入流,关流的代码.很累,很麻纺." 
所以,扩展了两个新的Controller,以简化对Ajax请求的处理. 
JSONObjectAbstractController 用于简单的从request.getParamater参数的情况. 
JSONObjectAbstractController 的原代码: 
Java代码 
package com.javaest.ext.spring.mvc.controller;   
  
import java.io.IOException;   
import java.io.PrintWriter;   
  
import javax.servlet.http.HttpServletRequest;   
import javax.servlet.http.HttpServletResponse;   
  
import net.sf.json.JSONObject;   
  
import org.springframework.web.servlet.ModelAndView;   
import org.springframework.web.servlet.mvc.AbstractController;   
  
public abstract class JSONObjectAbstractController extends AbstractController {   
  
    @Override  
    protected ModelAndView handleRequestInternal(HttpServletRequest request, HttpServletResponse response)   
            throws Exception {   
        JSONObject jsonObject = handleAjaxRequestInternal(request, response);   
        response.setContentType("text/Xml;charset=gbk");   
        PrintWriter out = null;   
        try {   
            out = response.getWriter();   
            out.println(jsonObject.toString());   
        }   
        catch (IOException ex1) {   
            ex1.printStackTrace();   
        }   
        finally {   
            out.close();   
        }   
  
        return null;   
    }   
  
    protected abstract JSONObject handleAjaxRequestInternal(HttpServletRequest httpServletRequest,   
            HttpServletResponse httpServletResponse) throws Exception;   
  
}  

package com.javaest.ext.spring.mvc.controller;

import java.io.IOException;
import java.io.PrintWriter;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import net.sf.json.JSONObject;

import org.springframework.web.servlet.ModelAndView;
import org.springframework.web.servlet.mvc.AbstractController;

public abstract class JSONObjectAbstractController extends AbstractController {

        @Override
        protected ModelAndView handleRequestInternal(HttpServletRequest request, HttpServletResponse response)
                        throws Exception {
                JSONObject jsonObject = handleAjaxRequestInternal(request, response);
                response.setContentType("text/Xml;charset=gbk");
                PrintWriter out = null;
                try {
                        out = response.getWriter();
                        out.println(jsonObject.toString());
                }
                catch (IOException ex1) {
                        ex1.printStackTrace();
                }
                finally {
                        out.close();
                }

                return null;
        }

        protected abstract JSONObject handleAjaxRequestInternal(HttpServletRequest httpServletRequest,
                        HttpServletResponse httpServletResponse) throws Exception;

}

JSONObjectSimpleFormController 用于自动将请求参数绑定到Command对象的情况. 
JSONObjectSimpleFormController 的代码: 
Java代码 
package com.javaest.ext.spring.mvc.controller;   
  
import java.io.IOException;   
import java.io.PrintWriter;   
  
import javax.servlet.http.HttpServletRequest;   
import javax.servlet.http.HttpServletResponse;   
  
import net.sf.json.JSONObject;   
  
import org.springframework.validation.BindException;   
import org.springframework.web.servlet.ModelAndView;   
import org.springframework.web.servlet.mvc.SimpleFormController;   
  
public abstract class JSONObjectSimpleFormController extends SimpleFormController {   
  
    @Override  
    protected ModelAndView onSubmit(HttpServletRequest request, HttpServletResponse response, Object cmd,   
            BindException ex) {   
        JSONObject object = onAjaxSubmit(request, response, cmd, ex);   
  
        response.setContentType("text/Xml;charset=gbk");   
        PrintWriter out = null;   
        try {   
            out = response.getWriter();   
            out.println(object.toString());   
        }   
        catch (IOException ex1) {   
            ex1.printStackTrace();   
        }   
        finally {   
            out.close();   
        }   
  
        return null;   
    }   
  
    public abstract JSONObject onAjaxSubmit(HttpServletRequest request, HttpServletResponse response, Object cmd,   
            BindException ex);   
  
}  

package com.javaest.ext.spring.mvc.controller;

import java.io.IOException;
import java.io.PrintWriter;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import net.sf.json.JSONObject;

import org.springframework.validation.BindException;
import org.springframework.web.servlet.ModelAndView;
import org.springframework.web.servlet.mvc.SimpleFormController;

public abstract class JSONObjectSimpleFormController extends SimpleFormController {

        @Override
        protected ModelAndView onSubmit(HttpServletRequest request, HttpServletResponse response, Object cmd,
                        BindException ex) {
                JSONObject object = onAjaxSubmit(request, response, cmd, ex);

                response.setContentType("text/Xml;charset=gbk");
                PrintWriter out = null;
                try {
                        out = response.getWriter();
                        out.println(object.toString());
                }
                catch (IOException ex1) {
                        ex1.printStackTrace();
                }
                finally {
                        out.close();
                }

                return null;
        }

        public abstract JSONObject onAjaxSubmit(HttpServletRequest request, HttpServletResponse response, Object cmd,
                        BindException ex);

}