spring mvc MultiActionController 实现 SimpleFormController 自动封装form

最新推荐文章于 2023-01-27 13:46:48 发布

原创最新推荐文章于 2023-01-27 13:46:48 发布 · 149 阅读

0 ·

CC 4.0 BY-SA版权

文章标签：

#MVC #Spring #Java #Servlet #Web

本文介绍了一种在Spring MVC框架中使用MultiController时，针对复杂对象及集合类型的自定义绑定方法。作者通过反射机制实现了对子对象的自动填充，并提供了一段具体的实现代码。

一直没在这写过今天突然高兴，昨天搜到大家在用spring mvc时对 multi controller 对form的搜集并没有好的处理方法尤其是对子对象的操作

废话不说了先说思路
1 通过测试我发现如果对象结构是这样

public class User {

	private String username;
	private String password;
	private Address address;

那么


	public ModelAndView saveHandler(HttpServletRequest request,HttpServletResponse response,Object command) throws Exception{
		User user=new User();
		user.setAddress(new Address());
		bind(request, user);
		System.out.println(user);
		return new ModelAndView();
	}

即可因此为了通用我用我就想用反射取出主对象中的从对象然后调用set方法终于功夫不负苦心人几经摸索终于探索出几行代码用的java.beans 里的类要是不看spring 还真知道这个类
既然如此就干脆 override bind方法吧呵呵刚开始写了这个

@Override
 protected void bind(HttpServletRequest request, Object command) throws Exception{
        BeanInfo beanInfo= Introspector.getBeanInfo(command.getClass());
        PropertyDescriptor[] pds = beanInfo.getPropertyDescriptors();
        for(PropertyDescriptor pd:pds){
         if(!BeanUtils.isSimpleProperty(pd.getPropertyType())){
          pd.getWriteMethod().invoke(command,pd.getPropertyType().newInstance());
         }
        }
       super.bind(request, command);

 }

最后找了找发现 BeanUtils 类里方法真全而且写的也比用apache 本身的好（个人感觉啊）所以得出代码

package com.llb.web;

import java.beans.PropertyDescriptor;

import javax.servlet.http.HttpServletRequest;

import org.springframework.beans.BeanUtils;
import org.springframework.web.servlet.mvc.multiaction.MultiActionController;

public class BaseController extends MultiActionController {

	@Override
	protected void bind(HttpServletRequest request, Object command) throws Exception{
        PropertyDescriptor[] pds=BeanUtils.getPropertyDescriptors(command.getClass());
        for(PropertyDescriptor pd:pds){
        	if(!BeanUtils.isSimpleProperty(pd.getPropertyType())){
        		pd.getWriteMethod().invoke(command,pd.getPropertyType().newInstance());
        	}
        }
       super.bind(request, command);

	}

}

为了继续验证是否正确我定义了近可能多的属性

public class User {

	private String username;
	private String password;
	private Address address;

	private boolean flag;
	private int count;
	private Date createDate;
	private double doubleParam;
	private float floatParam;
	private byte byteParam;
	private short shortParam;
	private long longParam;
	private char charParam;

	private Collection collection;
	private List<String> list=new ArrayList<String>(0);;
	private ArrayList arrayList;
	private LinkedList linkedList;

	private Set set;
	private HashSet<String> hashSet=new HashSet<String>(0);
	private LinkedHashSet linkedHashSet;

	private com.sun.xml.xsom.impl.scd.Iterators.Map map;
	private java.util.Map mapp;
	private HashMap hashMap;
	private LinkedHashMap<String, String> linkedHashMap=new LinkedHashMap<String, String>(0);

	private Boolean boolean1;
	private Integer interger1;
	private Double double1;
	private Float float1;
	private Character char1;

	private String[] strArray;
	private int[] intArray;

发现不对集合类和非声明的对象还是有问题于是继续改代码

Class<?> clas=pd.getPropertyType();
        	boolean isSimpleProperty=BeanUtils.isSimpleProperty(clas);
        	boolean isInterface=clas.isInterface();
        	boolean hasConstruct=clas.getConstructors().length==0?false:true;
        	if(!isSimpleProperty&&!isInterface&&hasConstruct){
        		pd.getWriteMethod().invoke(command,clas.newInstance());
        	}

到现在已经是晚上12点多，不做测试了等以后有bug了再继续吧欢迎朋友们提bug 最后发布最终版（今日）代码

package com.llb.web;

import java.beans.PropertyDescriptor;
import javax.servlet.http.HttpServletRequest;
import org.springframework.beans.BeanUtils;
import org.springframework.web.servlet.mvc.multiaction.MultiActionController;

public class BaseController extends MultiActionController {

	@Override
	protected void bind(HttpServletRequest request, Object command) throws Exception{
        PropertyDescriptor[] pds=BeanUtils.getPropertyDescriptors(command.getClass());
        for(PropertyDescriptor pd:pds){
        	Class<?> clas=pd.getPropertyType();
        	boolean isSimpleProperty=BeanUtils.isSimpleProperty(clas);
        	boolean isInterface=clas.isInterface();
        	boolean hasConstruct=clas.getConstructors().length==0?false:true;
        	if(!isSimpleProperty&&!isInterface&&hasConstruct){
        		pd.getWriteMethod().invoke(command,clas.newInstance());
        	}
        }
       super.bind(request, command);

	}

}

至于 view层的form 可以直接 xx.xx了 <input type="text" name="address.name"

好累以后再写吧
我还写过一个 ext的封装组件思路不过一直欣赏 renren网有兴趣的同志可以搜下啊哈
http://blog.renren.com/blog/225311006/479329473?isDeclare=false