SpringMVC（5）：MVC的参数传递详解与示例（简单类型数据、ModelAndView、Model 、 POJO 以及 Map）

Easter79
• 阅读 586

2018/1/7

SpringMVC是一个以模型数据为核心的开源框架，将前后端松耦合的管理，最重要的就是数据的传递。

下面给大家介绍的是把参数值传递，包括使用简单类型数据、ModelAndView、Model 、POJO 以及 Map。

一、（View to Conotroller） URL传值--@RequestMapping

【1】修改IndexController.java：

package com.smbms.controller;

import org.apache.log4j.Logger;
import org.apache.log4j.PropertyConfigurator;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.servlet.ModelAndView;

@Controller 
@RequestMapping("/a")
public class IndexController {
    private Logger log = Logger.getLogger(IndexController.class.getName());

    @RequestMapping(value="/hello",method=RequestMethod.POST,params="username")
    public String hello(@RequestParam String username){
        log.info("welcome username1 ,"+username);
        return "hello";
    }
    
}

【2】在index.html 修改：

<%@ page language="java" contentType="text/html; charset=ISO-8859-1"
    pageEncoding="ISO-8859-1"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
<title>Insert title here</title>
</head>
<body>
    <a href="http://www.baidu.com">click</a>
    <a href="https://my.oschina.net//u/4689327/blog/4663859/hello?username=mmb">hello</a>
</body>
</html>

解释：（1）@RequestMapping 负责将不同的请求映射到对应的控制器方法上；

（2）@RequestMapping 的请求信息必须保持全局唯一，处理修饰方法，也可以修饰类；

（3）@RequestMapping 除了URL 映射请求，还可以使用请求参数、请求方法来映射请求，多条件可以让请求更加精确，匹配顺序为：首先value，然后method，最后参数；

输出结果：

18/01/07 11:08:17 INFO controller.IndexController: welcome username ,mmb

二、（View to Conotroller） URL传值--@RequestParam

【1】修改IndexController.java： 

package com.smbms.controller;

import org.apache.log4j.Logger;
import org.apache.log4j.PropertyConfigurator;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.servlet.ModelAndView;

@Controller 
@RequestMapping("/a")
public class IndexController {
    private Logger log = Logger.getLogger(IndexController.class.getName());
    
   //@RequestParam
    @RequestMapping(value="/hello")
    public String hello2(@RequestParam(value="username" ,required=false) String username){
     log.info("welcome username2 ,"+username);
     return "hello";
    }
}

【2】输出结果：

18/01/07 11:12:46 INFO controller.IndexController: welcome username2 ,mmb

解释：（1）@RequestParam 注解指定对应的请求参数。@RequestParam 有以三个参数：value（参数名）、required（参数是否必须）、defaultValue（不推荐）；

三、（Conotroller to View ）

对于mvc，模型数据最重要，Controller产生了Model，View最终也是为了渲染模型数据并进行输出：

1、ModelAndView

既包含视图信息，也包含模型数据。IndexController.java 做修改，将前端URL传参，在控制台输出参数值，并在视图层输出username；

【1】IndexController.java： 

package com.smbms.controller;

import org.apache.log4j.Logger;
import org.apache.log4j.PropertyConfigurator;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.servlet.ModelAndView;

@Controller 
@RequestMapping("/a")
public class IndexController {
    private Logger log = Logger.getLogger(IndexController.class.getName());
      
    //ModelAndView
    @RequestMapping(value="/hello")
    public ModelAndView hello3(@RequestParam(value="username3" ,required=true) String username3){
        log.info("welcome username3 ,"+username3);
        ModelAndView mView = new ModelAndView();
        mView.addObject("username",username3);
        mView.setViewName("hello");
        return mView;
    }
}

【2】在index.html 修改： 

<%@ page language="java" contentType="text/html; charset=ISO-8859-1"
    pageEncoding="ISO-8859-1"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
<title>Insert title here</title>
</head>
<body>
    <a href="http://www.baidu.com">click</a>        
    <a href="https://my.oschina.net//u/4689327/blog/4663859/hello?username=mmb">hello-username</a>
    <a href="https://my.oschina.net//u/4689327/blog/4663859/hello?usernameA=mmb">hello-usernameA</a>
</body>
</html>

【3】输出结果：

18/01/07 11:29:24 INFO controller.IndexController: welcome usernameA ,mmb

SpringMVC（5）：MVC的参数传递详解与示例（简单类型数据、ModelAndView、Model 、 POJO 以及 Map）

解释：（1）ModelAndView 对象介绍（官方文档）：

org.springframework.web.servlet 
Class ModelAndView

java.lang.Object
  org.springframework.web.servlet.ModelAndView

public class ModelAndView
   
    extends 
    Object

Constructor Summary

**[ModelAndView](http://tool.oschina.net/uploads/apidocs/Spring-3.1.1/org/springframework/web/servlet/ModelAndView.html#ModelAndView%28%29)**() 
          Default constructor for bean-style usage: populating bean properties instead of passing in constructor arguments.

**[ModelAndView](http://tool.oschina.net/uploads/apidocs/Spring-3.1.1/org/springframework/web/servlet/ModelAndView.html#ModelAndView%28java.lang.String%29)**([String](https://www.oschina.net/action/GoToLink?url=http%3A%2F%2Fdownload.oracle.com%2Fjavase%2F6%2Fdocs%2Fapi%2Fjava%2Flang%2FString.html%3Fis-external%3Dtrue) viewName) 
          Convenient constructor when there is no model data to expose.

**[ModelAndView](http://tool.oschina.net/uploads/apidocs/Spring-3.1.1/org/springframework/web/servlet/ModelAndView.html#ModelAndView%28java.lang.String,%20java.util.Map%29)**([String](https://www.oschina.net/action/GoToLink?url=http%3A%2F%2Fdownload.oracle.com%2Fjavase%2F6%2Fdocs%2Fapi%2Fjava%2Flang%2FString.html%3Fis-external%3Dtrue) viewName, [Map](https://www.oschina.net/action/GoToLink?url=http%3A%2F%2Fdownload.oracle.com%2Fjavase%2F6%2Fdocs%2Fapi%2Fjava%2Futil%2FMap.html%3Fis-external%3Dtrue)<[String](https://www.oschina.net/action/GoToLink?url=http%3A%2F%2Fdownload.oracle.com%2Fjavase%2F6%2Fdocs%2Fapi%2Fjava%2Flang%2FString.html%3Fis-external%3Dtrue),?> model) 
          Creates new ModelAndView given a view name and a model.

**[ModelAndView](http://tool.oschina.net/uploads/apidocs/Spring-3.1.1/org/springframework/web/servlet/ModelAndView.html#ModelAndView%28java.lang.String,%20java.lang.String,%20java.lang.Object%29)**([String](https://www.oschina.net/action/GoToLink?url=http%3A%2F%2Fdownload.oracle.com%2Fjavase%2F6%2Fdocs%2Fapi%2Fjava%2Flang%2FString.html%3Fis-external%3Dtrue) viewName, [String](https://www.oschina.net/action/GoToLink?url=http%3A%2F%2Fdownload.oracle.com%2Fjavase%2F6%2Fdocs%2Fapi%2Fjava%2Flang%2FString.html%3Fis-external%3Dtrue) modelName, [Object](https://www.oschina.net/action/GoToLink?url=http%3A%2F%2Fdownload.oracle.com%2Fjavase%2F6%2Fdocs%2Fapi%2Fjava%2Flang%2FObject.html%3Fis-external%3Dtrue) modelObject) 
          Convenient constructor to take a single model object.

**[ModelAndView](http://tool.oschina.net/uploads/apidocs/Spring-3.1.1/org/springframework/web/servlet/ModelAndView.html#ModelAndView%28org.springframework.web.servlet.View%29)**([View](http://tool.oschina.net/uploads/apidocs/Spring-3.1.1/org/springframework/web/servlet/View.html) view) 
          Convenient constructor when there is no model data to expose.

**[ModelAndView](http://tool.oschina.net/uploads/apidocs/Spring-3.1.1/org/springframework/web/servlet/ModelAndView.html#ModelAndView%28org.springframework.web.servlet.View,%20java.util.Map%29)**([View](http://tool.oschina.net/uploads/apidocs/Spring-3.1.1/org/springframework/web/servlet/View.html) view, [Map](https://www.oschina.net/action/GoToLink?url=http%3A%2F%2Fdownload.oracle.com%2Fjavase%2F6%2Fdocs%2Fapi%2Fjava%2Futil%2FMap.html%3Fis-external%3Dtrue)<[String](https://www.oschina.net/action/GoToLink?url=http%3A%2F%2Fdownload.oracle.com%2Fjavase%2F6%2Fdocs%2Fapi%2Fjava%2Flang%2FString.html%3Fis-external%3Dtrue),?> model) 
          Creates new ModelAndView given a View object and a model.

**[ModelAndView](http://tool.oschina.net/uploads/apidocs/Spring-3.1.1/org/springframework/web/servlet/ModelAndView.html#ModelAndView%28org.springframework.web.servlet.View,%20java.lang.String,%20java.lang.Object%29)**([View](http://tool.oschina.net/uploads/apidocs/Spring-3.1.1/org/springframework/web/servlet/View.html) view, [String](https://www.oschina.net/action/GoToLink?url=http%3A%2F%2Fdownload.oracle.com%2Fjavase%2F6%2Fdocs%2Fapi%2Fjava%2Flang%2FString.html%3Fis-external%3Dtrue) modelName, [Object](https://www.oschina.net/action/GoToLink?url=http%3A%2F%2Fdownload.oracle.com%2Fjavase%2F6%2Fdocs%2Fapi%2Fjava%2Flang%2FObject.html%3Fis-external%3Dtrue) modelObject) 
          Convenient constructor to take a single model object.

Method Summary

[ModelAndView](http://tool.oschina.net/uploads/apidocs/Spring-3.1.1/org/springframework/web/servlet/ModelAndView.html)

**[addAllObjects](http://tool.oschina.net/uploads/apidocs/Spring-3.1.1/org/springframework/web/servlet/ModelAndView.html#addAllObjects%28java.util.Map%29)**([Map](https://www.oschina.net/action/GoToLink?url=http%3A%2F%2Fdownload.oracle.com%2Fjavase%2F6%2Fdocs%2Fapi%2Fjava%2Futil%2FMap.html%3Fis-external%3Dtrue)<[String](https://www.oschina.net/action/GoToLink?url=http%3A%2F%2Fdownload.oracle.com%2Fjavase%2F6%2Fdocs%2Fapi%2Fjava%2Flang%2FString.html%3Fis-external%3Dtrue),?> modelMap) 
          Add all attributes contained in the provided Map to the model.

[ModelAndView](http://tool.oschina.net/uploads/apidocs/Spring-3.1.1/org/springframework/web/servlet/ModelAndView.html)

**[addObject](http://tool.oschina.net/uploads/apidocs/Spring-3.1.1/org/springframework/web/servlet/ModelAndView.html#addObject%28java.lang.Object%29)**([Object](https://www.oschina.net/action/GoToLink?url=http%3A%2F%2Fdownload.oracle.com%2Fjavase%2F6%2Fdocs%2Fapi%2Fjava%2Flang%2FObject.html%3Fis-external%3Dtrue) attributeValue) 
          Add an attribute to the model using parameter name generation.

[ModelAndView](http://tool.oschina.net/uploads/apidocs/Spring-3.1.1/org/springframework/web/servlet/ModelAndView.html)

**[addObject](http://tool.oschina.net/uploads/apidocs/Spring-3.1.1/org/springframework/web/servlet/ModelAndView.html#addObject%28java.lang.String,%20java.lang.Object%29)**([String](https://www.oschina.net/action/GoToLink?url=http%3A%2F%2Fdownload.oracle.com%2Fjavase%2F6%2Fdocs%2Fapi%2Fjava%2Flang%2FString.html%3Fis-external%3Dtrue) attributeName, [Object](https://www.oschina.net/action/GoToLink?url=http%3A%2F%2Fdownload.oracle.com%2Fjavase%2F6%2Fdocs%2Fapi%2Fjava%2Flang%2FObject.html%3Fis-external%3Dtrue) attributeValue) 
          Add an attribute to the model.

void

**[clear](http://tool.oschina.net/uploads/apidocs/Spring-3.1.1/org/springframework/web/servlet/ModelAndView.html#clear%28%29)**() 
          Clear the state of this ModelAndView object.

[Map](https://www.oschina.net/action/GoToLink?url=http%3A%2F%2Fdownload.oracle.com%2Fjavase%2F6%2Fdocs%2Fapi%2Fjava%2Futil%2FMap.html%3Fis-external%3Dtrue)<[String](https://www.oschina.net/action/GoToLink?url=http%3A%2F%2Fdownload.oracle.com%2Fjavase%2F6%2Fdocs%2Fapi%2Fjava%2Flang%2FString.html%3Fis-external%3Dtrue),[Object](https://www.oschina.net/action/GoToLink?url=http%3A%2F%2Fdownload.oracle.com%2Fjavase%2F6%2Fdocs%2Fapi%2Fjava%2Flang%2FObject.html%3Fis-external%3Dtrue)>

**[getModel](http://tool.oschina.net/uploads/apidocs/Spring-3.1.1/org/springframework/web/servlet/ModelAndView.html#getModel%28%29)**() 
          Return the model map.

protected  [Map](https://www.oschina.net/action/GoToLink?url=http%3A%2F%2Fdownload.oracle.com%2Fjavase%2F6%2Fdocs%2Fapi%2Fjava%2Futil%2FMap.html%3Fis-external%3Dtrue)<[String](https://www.oschina.net/action/GoToLink?url=http%3A%2F%2Fdownload.oracle.com%2Fjavase%2F6%2Fdocs%2Fapi%2Fjava%2Flang%2FString.html%3Fis-external%3Dtrue),[Object](https://www.oschina.net/action/GoToLink?url=http%3A%2F%2Fdownload.oracle.com%2Fjavase%2F6%2Fdocs%2Fapi%2Fjava%2Flang%2FObject.html%3Fis-external%3Dtrue)>

**[getModelInternal](http://tool.oschina.net/uploads/apidocs/Spring-3.1.1/org/springframework/web/servlet/ModelAndView.html#getModelInternal%28%29)**() 
          Return the model map.

[ModelMap](http://tool.oschina.net/uploads/apidocs/Spring-3.1.1/org/springframework/ui/ModelMap.html)

**[getModelMap](http://tool.oschina.net/uploads/apidocs/Spring-3.1.1/org/springframework/web/servlet/ModelAndView.html#getModelMap%28%29)**() 
          Return the underlying ModelMap instance (never null).

[View](http://tool.oschina.net/uploads/apidocs/Spring-3.1.1/org/springframework/web/servlet/View.html)

**[getView](http://tool.oschina.net/uploads/apidocs/Spring-3.1.1/org/springframework/web/servlet/ModelAndView.html#getView%28%29)**() 
          Return the View object, or null if we are using a view name to be resolved by the DispatcherServlet via a ViewResolver.

[String](https://www.oschina.net/action/GoToLink?url=http%3A%2F%2Fdownload.oracle.com%2Fjavase%2F6%2Fdocs%2Fapi%2Fjava%2Flang%2FString.html%3Fis-external%3Dtrue)

**[getViewName](http://tool.oschina.net/uploads/apidocs/Spring-3.1.1/org/springframework/web/servlet/ModelAndView.html#getViewName%28%29)**() 
          Return the view name to be resolved by the DispatcherServlet via a ViewResolver, or null if we are using a View object.

boolean

**[hasView](http://tool.oschina.net/uploads/apidocs/Spring-3.1.1/org/springframework/web/servlet/ModelAndView.html#hasView%28%29)**() 
          Indicate whether or not this ModelAndView has a view, either as a view name or as a direct View instance.

boolean

**[isEmpty](http://tool.oschina.net/uploads/apidocs/Spring-3.1.1/org/springframework/web/servlet/ModelAndView.html#isEmpty%28%29)**() 
          Return whether this ModelAndView object is empty, i.e.

boolean

**[isReference](http://tool.oschina.net/uploads/apidocs/Spring-3.1.1/org/springframework/web/servlet/ModelAndView.html#isReference%28%29)**() 
          Return whether we use a view reference, i.e.

void

**[setView](http://tool.oschina.net/uploads/apidocs/Spring-3.1.1/org/springframework/web/servlet/ModelAndView.html#setView%28org.springframework.web.servlet.View%29)**([View](http://tool.oschina.net/uploads/apidocs/Spring-3.1.1/org/springframework/web/servlet/View.html) view) 
          Set a View object for this ModelAndView.

void

**[setViewName](http://tool.oschina.net/uploads/apidocs/Spring-3.1.1/org/springframework/web/servlet/ModelAndView.html#setViewName%28java.lang.String%29)**([String](https://www.oschina.net/action/GoToLink?url=http%3A%2F%2Fdownload.oracle.com%2Fjavase%2F6%2Fdocs%2Fapi%2Fjava%2Flang%2FString.html%3Fis-external%3Dtrue) viewName) 
          Set a view name for this ModelAndView, to be resolved by the DispatcherServlet via a ViewResolver.

[String](https://www.oschina.net/action/GoToLink?url=http%3A%2F%2Fdownload.oracle.com%2Fjavase%2F6%2Fdocs%2Fapi%2Fjava%2Flang%2FString.html%3Fis-external%3Dtrue)

**[toString](http://tool.oschina.net/uploads/apidocs/Spring-3.1.1/org/springframework/web/servlet/ModelAndView.html#toString%28%29)**() 
          Return diagnostic information about this model and view.

boolean

**[wasCleared](http://tool.oschina.net/uploads/apidocs/Spring-3.1.1/org/springframework/web/servlet/ModelAndView.html#wasCleared%28%29)**() 
          Return whether this ModelAndView object is empty as a result of a call to clear() i.e.

Methods inherited from class java.lang.Object

[clone](https://www.oschina.net/action/GoToLink?url=http%3A%2F%2Fdownload.oracle.com%2Fjavase%2F6%2Fdocs%2Fapi%2Fjava%2Flang%2FObject.html%3Fis-external%3Dtrue%23clone%2528%2529), [equals](https://www.oschina.net/action/GoToLink?url=http%3A%2F%2Fdownload.oracle.com%2Fjavase%2F6%2Fdocs%2Fapi%2Fjava%2Flang%2FObject.html%3Fis-external%3Dtrue%23equals%2528java.lang.Object%2529), [finalize](https://www.oschina.net/action/GoToLink?url=http%3A%2F%2Fdownload.oracle.com%2Fjavase%2F6%2Fdocs%2Fapi%2Fjava%2Flang%2FObject.html%3Fis-external%3Dtrue%23finalize%2528%2529), [getClass](https://www.oschina.net/action/GoToLink?url=http%3A%2F%2Fdownload.oracle.com%2Fjavase%2F6%2Fdocs%2Fapi%2Fjava%2Flang%2FObject.html%3Fis-external%3Dtrue%23getClass%2528%2529), [hashCode](https://www.oschina.net/action/GoToLink?url=http%3A%2F%2Fdownload.oracle.com%2Fjavase%2F6%2Fdocs%2Fapi%2Fjava%2Flang%2FObject.html%3Fis-external%3Dtrue%23hashCode%2528%2529), [notify](https://www.oschina.net/action/GoToLink?url=http%3A%2F%2Fdownload.oracle.com%2Fjavase%2F6%2Fdocs%2Fapi%2Fjava%2Flang%2FObject.html%3Fis-external%3Dtrue%23notify%2528%2529), [notifyAll](https://www.oschina.net/action/GoToLink?url=http%3A%2F%2Fdownload.oracle.com%2Fjavase%2F6%2Fdocs%2Fapi%2Fjava%2Flang%2FObject.html%3Fis-external%3Dtrue%23notifyAll%2528%2529), [wait](https://www.oschina.net/action/GoToLink?url=http%3A%2F%2Fdownload.oracle.com%2Fjavase%2F6%2Fdocs%2Fapi%2Fjava%2Flang%2FObject.html%3Fis-external%3Dtrue%23wait%2528%2529), [wait](https://www.oschina.net/action/GoToLink?url=http%3A%2F%2Fdownload.oracle.com%2Fjavase%2F6%2Fdocs%2Fapi%2Fjava%2Flang%2FObject.html%3Fis-external%3Dtrue%23wait%2528long%2529), [wait](https://www.oschina.net/action/GoToLink?url=http%3A%2F%2Fdownload.oracle.com%2Fjavase%2F6%2Fdocs%2Fapi%2Fjava%2Flang%2FObject.html%3Fis-external%3Dtrue%23wait%2528long%2C%2520int%2529)

2、Model 对象模型的使用

还可以使用Model对象完成模型数据的传递。
【1】修改IndexController.java：

package com.smbms.controller;

import org.apache.log4j.Logger;
import org.apache.log4j.PropertyConfigurator;
import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.servlet.ModelAndView;

@Controller 
@RequestMapping("/a")
public class IndexController {
    private Logger log = Logger.getLogger(IndexController.class.getName());
    
    //Model 
  @RequestMapping(value="/helloB")
  public String hello4(String usernameB ,Model model){
      log.info("welcome usernameB ,"+usernameB);
      model.addAttribute("usernameB",usernameB);
      return "helloB";
  }
}

【2】在index.jsp 修改： 

<%@ page language="java" contentType="text/html; charset=ISO-8859-1"
    pageEncoding="ISO-8859-1"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
<title>Insert title here</title>
</head>
<body>
    <a href="http://www.baidu.com">click</a>        
    <a href="https://my.oschina.net//u/4689327/blog/4663859/hello?username=mmb">hello-username</a>
    <a href="https://my.oschina.net//u/4689327/blog/4663859/hello?usernameA=mmb">hello-usernameA</a>
    <a href="https://my.oschina.net//u/4689327/blog/4663859/hello?usernameB=mmb">hello-usernameB</a>
</body>
</html>

【3】helloB.jsp：

<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Insert title here</title>
</head>
<body>
    <h1>bb</h1>
    <!-- ${usernameB}才是取值 -->
    <h1>usernameB(key:usernameB) --> ${usernameB}</h1>
</body>
</html>

【4】输出结果：

18/01/07 11:52:33 INFO controller.IndexController: welcome usernameB ,mmb

SpringMVC（5）：MVC的参数传递详解与示例（简单类型数据、ModelAndView、Model 、 POJO 以及 Map）

解释：（1）Model对象介绍（官方文档）：

org.springframework.ui 
Interface Model

All Known Subinterfaces:

RedirectAttributes

All Known Implementing Classes:

BindingAwareModelMap,  ExtendedModelMap,  RedirectAttributesModelMap

public interface Model

Method Summary

[Model](http://tool.oschina.net/uploads/apidocs/Spring-3.1.1/org/springframework/ui/Model.html)

**[addAllAttributes](http://tool.oschina.net/uploads/apidocs/Spring-3.1.1/org/springframework/ui/Model.html#addAllAttributes%28java.util.Collection%29)**([Collection](https://www.oschina.net/action/GoToLink?url=http%3A%2F%2Fdownload.oracle.com%2Fjavase%2F6%2Fdocs%2Fapi%2Fjava%2Futil%2FCollection.html%3Fis-external%3Dtrue)<?> attributeValues) 
          Copy all attributes in the supplied Collection into this Map, using attribute name generation for each element.

[Model](http://tool.oschina.net/uploads/apidocs/Spring-3.1.1/org/springframework/ui/Model.html)

**[addAllAttributes](http://tool.oschina.net/uploads/apidocs/Spring-3.1.1/org/springframework/ui/Model.html#addAllAttributes%28java.util.Map%29)**([Map](https://www.oschina.net/action/GoToLink?url=http%3A%2F%2Fdownload.oracle.com%2Fjavase%2F6%2Fdocs%2Fapi%2Fjava%2Futil%2FMap.html%3Fis-external%3Dtrue)<[String](https://www.oschina.net/action/GoToLink?url=http%3A%2F%2Fdownload.oracle.com%2Fjavase%2F6%2Fdocs%2Fapi%2Fjava%2Flang%2FString.html%3Fis-external%3Dtrue),?> attributes) 
          Copy all attributes in the supplied Map into this Map.

[Model](http://tool.oschina.net/uploads/apidocs/Spring-3.1.1/org/springframework/ui/Model.html)

**[addAttribute](http://tool.oschina.net/uploads/apidocs/Spring-3.1.1/org/springframework/ui/Model.html#addAttribute%28java.lang.Object%29)**([Object](https://www.oschina.net/action/GoToLink?url=http%3A%2F%2Fdownload.oracle.com%2Fjavase%2F6%2Fdocs%2Fapi%2Fjava%2Flang%2FObject.html%3Fis-external%3Dtrue) attributeValue) 
          Add the supplied attribute to this Map using a generated name.

[Model](http://tool.oschina.net/uploads/apidocs/Spring-3.1.1/org/springframework/ui/Model.html)

**[addAttribute](http://tool.oschina.net/uploads/apidocs/Spring-3.1.1/org/springframework/ui/Model.html#addAttribute%28java.lang.String,%20java.lang.Object%29)**([String](https://www.oschina.net/action/GoToLink?url=http%3A%2F%2Fdownload.oracle.com%2Fjavase%2F6%2Fdocs%2Fapi%2Fjava%2Flang%2FString.html%3Fis-external%3Dtrue) attributeName, [Object](https://www.oschina.net/action/GoToLink?url=http%3A%2F%2Fdownload.oracle.com%2Fjavase%2F6%2Fdocs%2Fapi%2Fjava%2Flang%2FObject.html%3Fis-external%3Dtrue) attributeValue) 
          Add the supplied attribute under the supplied name.

[Map](https://www.oschina.net/action/GoToLink?url=http%3A%2F%2Fdownload.oracle.com%2Fjavase%2F6%2Fdocs%2Fapi%2Fjava%2Futil%2FMap.html%3Fis-external%3Dtrue)<[String](https://www.oschina.net/action/GoToLink?url=http%3A%2F%2Fdownload.oracle.com%2Fjavase%2F6%2Fdocs%2Fapi%2Fjava%2Flang%2FString.html%3Fis-external%3Dtrue),[Object](https://www.oschina.net/action/GoToLink?url=http%3A%2F%2Fdownload.oracle.com%2Fjavase%2F6%2Fdocs%2Fapi%2Fjava%2Flang%2FObject.html%3Fis-external%3Dtrue)>

**[asMap](http://tool.oschina.net/uploads/apidocs/Spring-3.1.1/org/springframework/ui/Model.html#asMap%28%29)**() 
          Return the current set of model attributes as a Map.

boolean

**[containsAttribute](http://tool.oschina.net/uploads/apidocs/Spring-3.1.1/org/springframework/ui/Model.html#containsAttribute%28java.lang.String%29)**([String](https://www.oschina.net/action/GoToLink?url=http%3A%2F%2Fdownload.oracle.com%2Fjavase%2F6%2Fdocs%2Fapi%2Fjava%2Flang%2FString.html%3Fis-external%3Dtrue) attributeName) 
          Does this model contain an attribute of the given name?

[Model](http://tool.oschina.net/uploads/apidocs/Spring-3.1.1/org/springframework/ui/Model.html)

**[mergeAttributes](http://tool.oschina.net/uploads/apidocs/Spring-3.1.1/org/springframework/ui/Model.html#mergeAttributes%28java.util.Map%29)**([Map](https://www.oschina.net/action/GoToLink?url=http%3A%2F%2Fdownload.oracle.com%2Fjavase%2F6%2Fdocs%2Fapi%2Fjava%2Futil%2FMap.html%3Fis-external%3Dtrue)<[String](https://www.oschina.net/action/GoToLink?url=http%3A%2F%2Fdownload.oracle.com%2Fjavase%2F6%2Fdocs%2Fapi%2Fjava%2Flang%2FString.html%3Fis-external%3Dtrue),?> attributes) 
          Copy all attributes in the supplied Map into this Map, with existing objects of the same name taking precedence (i.e.

（2）其实springmvc 在调用方法前，就会创建一个隐含的模型对象（隐含模型）Model，作为数据的存储容器。那么，若处理方法的入参为Model模型，springmvc就会将隐含模型的引用传递给这些入参；简单说，开发者可以通过一个Model类型的入参对象，访问到模型的所有数据，当然也可以添加新的属性数据！

【4】添加无key值的属性，修改IndexController.java：：

package com.smbms.controller;

import org.apache.log4j.Logger;
import org.apache.log4j.PropertyConfigurator;
import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.servlet.ModelAndView;

@Controller 
@RequestMapping("/a")
public class IndexController {
    private Logger log = Logger.getLogger(IndexController.class.getName());
      
    //Model 
  @RequestMapping(value="/hello")
  public String hello4(String usernameB ,Model model){
    Integer value = 110; 
      log.info("welcome usernameB ,"+usernameB);
      model.addAttribute("usernameB",usernameB);
      model.addAttribute(usernameB);
      model.addAttribute(value);
      return "helloB";
  }
}

输出结果：

18/01/07 12:07:39 INFO controller.IndexController: welcome usernameB ,mmb是否包含string :true是否包含integer:true

SpringMVC（5）：MVC的参数传递详解与示例（简单类型数据、ModelAndView、Model 、 POJO 以及 Map）

解释：（3）Model对象使用无参属性是，参数的类型名称会成为其默认的key！！大家可以自主探究：对于使用多个相同类型的无key参数，调用会出错吗？参数的key区分大小写吗？（答案：区分大小写！多个参数时，若是没有通过变量赋值，是取不出来的！）

3、POJO 对象模型的使用

【0】在工程新建一个包，新建一个JavaBean，这里举例User.java：

package com.smbms.entities;

import java.util.Date;
import java.util.List;

public class User {
    private Integer id;
    private String userCode;
    private String userName;
    private String userPassword;
    private Integer gender;
    private Date birthday;
    private String phone;
    private String address ;
    private Integer userRole;
    private Integer createdBy;
    private Date creationDate;
    private Integer modifyBy;
    private Date modifyDate;
    private String userRoleName;
        
        public String getUserRoleName() {
        return userRoleName;
    }
    public void setUserRoleName(String userRoleName) {
        this.userRoleName = userRoleName;
    }
    public Integer getId() {
        return id;
    }
    public void setId(Integer id) {
        this.id = id;
    }
    public String getUserCode() {
        return userCode;
    }
    public void setUserCode(String userCode) {
        this.userCode = userCode;
    }
    public String getUserName() {
        return userName;
    }
    public void setUserName(String userName) {
        this.userName = userName;
    }
    public String getUserPassword() {
        return userPassword;
    }
    public void setUserPassword(String userPassword) {
        this.userPassword = userPassword;
    }
    public Integer getGender() {
        return gender;
    }
    public void setGender(Integer gender) {
        this.gender = gender;
    }
    public Date getBirthday() {
        return birthday;
    }
    public void setBirthday(Date birthday) {
        this.birthday = birthday;
    }
    public String getPhone() {
        return phone;
    }
    public void setPhone(String phone) {
        this.phone = phone;
    }
    public String getAddress() {
        return address;
    }
    public void setAddress(String address) {
        this.address = address;
    }
    public Integer getUserRole() {
        return userRole;
    }
    public void setUserRole(Integer userRole) {
        this.userRole = userRole;
    }
    public Integer getCreatedBy() {
        return createdBy;
    }
    public void setCreatedBy(Integer createdBy) {
        this.createdBy = createdBy;
    }
    public Date getCreationDate() {
        return creationDate;
    }
    public void setCreationDate(Date creationDate) {
        this.creationDate = creationDate;
    }
    public Integer getModifyBy() {
        return modifyBy;
    }
    public void setModifyBy(Integer modifyBy) {
        this.modifyBy = modifyBy;
    }
    public Date getModifyDate() {
        return modifyDate;
    }
    public void setModifyDate(Date modifyDate) {
        this.modifyDate = modifyDate;
    }
    public User(Integer id, String userCode, String userName, String userPassword, Integer gender, Date birthday,
            String phone, String address, Integer userRole, Integer createdBy, Date creationDate, Integer modifyBy,
            Date modifyDate) {
        super();
        this.id = id;
        this.userCode = userCode;
        this.userName = userName;
        this.userPassword = userPassword;
        this.gender = gender;
        this.birthday = birthday;
        this.phone = phone;
        this.address = address;
        this.userRole = userRole;
        this.createdBy = createdBy;
        this.creationDate = creationDate;
        this.modifyBy = modifyBy;
        this.modifyDate = modifyDate;
    }
    public User() {
        super();
        // TODO 自动生成的构造函数存根
    }
    @Override
    public String toString() {
        return "User [id=" + id + ", userCode=" + userCode + ", userName=" + userName + ", userPassword=" + userPassword
                + ", gender=" + gender + ", birthday=" + birthday + ", phone=" + phone + ", address=" + address
                + ", userRole=" + userRole + ", createdBy=" + createdBy + ", creationDate=" + creationDate
                + ", modifyBy=" + modifyBy + ", modifyDate=" + modifyDate + "]";
    }
    
}

【1】修改IndexController.java：

package com.smbms.controller; import org.apache.log4j.Logger; import org.apache.log4j.PropertyConfigurator; import org.springframework.stereotype.Controller; import org.springframework.ui.Model; import org.springframework.web.bind.annotation.RequestMapping; import org.springframework.web.bind.annotation.RequestParam; import org.springframework.web.servlet.ModelAndView; import com.smbms.entities.User; @Controller  @RequestMapping("/a") public class IndexController {  private Logger log = Logger.getLogger(IndexController.class.getName());        //POJO+Model   @RequestMapping(value="/hello")   public String hello5(String usernameB ,Model model){    model.addAttribute("usernameB",usernameB);    model.addAttribute(usernameB);    User user = new User();    user.setUserName(usernameB);    model.addAttribute("currentUser", user);    model.addAttribute(user);    return "helloB";   } }  

【2】index.jsp 不作修改；

【3】helloB.jsp：

<%@ page language="java" contentType="text/html; charset=UTF-8"     pageEncoding="UTF-8"%> <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> <html> <head> <meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> <title>Insert title here</title> </head> <body>  <h1>bb</h1>  <table width="500">  <tr>  <td>  <!-- ${usernameB}才是取值 -->  <h1>usernameB(key:usernameB) --> ${usernameB}</h1>  </td>  </tr>  <tr><td>  <h1>无key值(key:string) --> ${string}</h1>   </td></tr>  <tr><td>  <h1>无key值(key:integer)  --> ${integer}</h1>  </td></tr>    <tr><td>  <h1>有key值(key:currentUser.userName)  --> ${currentUser.userName}</h1>  </td>  </tr>    <tr><td>  <h1>无key值(key:user.userName)  --> ${user.userName}</h1>  </td></tr>  </table>   </body> </html>

【4】输出结果：

SpringMVC（5）：MVC的参数传递详解与示例（简单类型数据、ModelAndView、Model 、 POJO 以及 Map）

解释：还是使用“.”进行属性值的访问。

4、Map 对象模型的使用

不难发现，其实Model也是一个Map 的数据结构，所以，我们使用Map 作为处理方法入参也是可以的。

【1】修改IndexController.java：

package com.smbms.controller;

import java.util.Map;

import org.apache.log4j.Logger;
import org.apache.log4j.PropertyConfigurator;
import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.servlet.ModelAndView;

import com.smbms.entities.User;

@Controller 
@RequestMapping("/a")
public class IndexController {
    private Logger log = Logger.getLogger(IndexController.class.getName());
  
  //Map
  @RequestMapping(value="/hello")
  public String index(String username,Map<String,Object>model){
      log.info("hello springmvc!username:"+username);
      model.put("usernameKK", username);
      return "helloC";
  }
}

【2】 index.jsp 不作修改；

【3】新建helloC.jsp：

<%@ page language="java" contentType="text/html; charset=ISO-8859-1"
    pageEncoding="ISO-8859-1"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
<title>Insert title here</title>
</head>
<body>
    <h1>hello springmvc!</h1>
    <h2>username(key:username) --> ${username}</h2>
    <h2>username(key:usernameKK) --> ${usernameKK}</h2>
</body>
</html>

【4】输出结果：

18/01/07 12:49:20 INFO controller.IndexController: hello springmvc!username:mmb

SpringMVC（5）：MVC的参数传递详解与示例（简单类型数据、ModelAndView、Model 、 POJO 以及 Map）

4、@ModelAttribute 对象模型的注解使用：

若希望将入参的数据对象放入数据模型，可以在相应的参数入参前使用该注解。后续做跟进。

5、@ModelAttributes 对象模型的注解使用：

此注解可以将模型的属性存入HttpSession中，以便多个请求之间共享该属性。后续做跟进。

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