Spring MVC 数据绑定入门

一.应用intellij IDEA创建SpringMVC项目

简单介绍一下，eclipse和idea有些概念上的差别

eclipse中的workspace相当于idea中的project
eclipse中的project相当于idea中的module

1.创建webApp项目

2.创建java文件

pom.wml文件

<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"  xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd">  <modelVersion>4.0.0</modelVersion>  <groupId>com.vishuo.springmvc</groupId>  <artifactId>springmvc</artifactId>  <packaging>war</packaging>  <version>1.0-SNAPSHOT</version>  <name>springmvc Maven Webapp</name>  <url>http://maven.apache.org</url>  <properties>    <org.springframework.version>4.0.0.RELEASE</org.springframework.version>  </properties>  <dependencies>    <dependency>      <groupId>junit</groupId>      <artifactId>junit</artifactId>      <version>3.8.1</version>      <scope>test</scope>    </dependency>    <dependency>      <groupId>org.apache.tomcat</groupId>      <artifactId>tomcat-servlet-api</artifactId>      <version>7.0.64</version>    </dependency>    <dependency>      <groupId>org.springframework</groupId>      <artifactId>spring-webmvc</artifactId>      <version>4.0.0.RELEASE</version>    </dependency>    <dependency>      <groupId>org.aspectj</groupId>      <artifactId>aspectjrt</artifactId>      <version>1.6.11</version>    </dependency>    <dependency>      <groupId>org.codehaus.jackson</groupId>      <artifactId>jackson-mapper-asl</artifactId>      <version>1.9.9</version>    </dependency>    <dependency>      <groupId>org.springframework</groupId>      <artifactId>spring-oxm</artifactId>      <version>4.0.0.RELEASE</version>    </dependency>    <dependency>      <groupId>junit</groupId>      <artifactId>junit</artifactId>      <version>4.6</version>    </dependency>  </dependencies>  <build>    <finalName>springmvc</finalName>  </build></project>

web.xml文件:

<!DOCTYPE web-app PUBLIC "-//Sun Microsystems, Inc.//DTD Web Application 2.3//EN" "http://java.sun.com/dtd/web-app_2_3.dtd" ><web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"         xmlns="http://java.sun.com/xml/ns/javaee"         xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd"         id="WebApp_ID" version="2.5">  <display-name>Archetype Created Web Application</display-name>  <context-param>    <param-name>contextConfigLocation</param-name>    <param-value>      classpath:applicationContext.xml    </param-value>  </context-param>  <listener>    <listener-class>org.springframework.web.context.request.RequestContextListener</listener-class>  </listener>  <listener>    <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>  </listener>  <servlet>    <servlet-name>dispatcher</servlet-name>    <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>    <load-on-startup>1</load-on-startup>  </servlet>  <filter>    <filter-name>characterEncodingFilter</filter-name>    <filter-class>org.springframework.web.filter.CharacterEncodingFilter</filter-class>    <init-param>      <param-name>encoding</param-name>      <param-value>UTF-8</param-value>    </init-param>  </filter>  <filter-mapping>    <filter-name>characterEncodingFilter</filter-name>    <url-pattern>/*</url-pattern>  </filter-mapping>  <servlet-mapping>    <servlet-name>dispatcher</servlet-name>    <url-pattern>/</url-pattern>  </servlet-mapping></web-app>

二.基本类型、包装类型的绑定

—基本类型

—包装类型

—数组

例如：age属性可以用基本类型int或者包装类型Integer
区别：
如果选择基本类型
1.key是必须传的
2.只能是int类型

如果传入错误，则后台报错400，如果不传，则报错500

如果是包装类型
1.可以不传key
则不会出现上面的错误，所有在开发过程中，如果定义一个参数有可能为空的情况，最好定义为包装类型。

当然，我们还可以通过@RequestRaram，对是否进行配置。

数组：
1.基本类型 2.包装类型 3.String的对象类型 都是可以传的

1》基本类型处理

项目演示：

pom.wxml文件：

<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd">  <modelVersion>4.0.0</modelVersion>  <groupId>com.imooc.demo</groupId>  <artifactId>springmvc</artifactId>  <packaging>war</packaging>  <version>0.0.1-SNAPSHOT</version>  <name>springmvc Maven Webapp</name>  <url>http://maven.apache.org</url>  <properties>    <org.springframework.version>4.0.0.RELEASE</org.springframework.version>  </properties>  <dependencies>    <dependency>      <groupId>junit</groupId>      <artifactId>junit</artifactId>      <version>3.8.1</version>      <scope>test</scope>    </dependency>    <dependency>      <groupId>org.apache.tomcat</groupId>      <artifactId>tomcat-servlet-api</artifactId>      <version>7.0.64</version>    </dependency>    <dependency>      <groupId>org.springframework</groupId>      <artifactId>spring-webmvc</artifactId>      <version>4.0.0.RELEASE</version>    </dependency>    <dependency>      <groupId>org.aspectj</groupId>      <artifactId>aspectjrt</artifactId>      <version>1.6.11</version>    </dependency>    <dependency>      <groupId>org.codehaus.jackson</groupId>      <artifactId>jackson-mapper-asl</artifactId>      <version>1.9.9</version>    </dependency>    <dependency>      <groupId>org.springframework</groupId>      <artifactId>spring-oxm</artifactId>      <version>4.0.0.RELEASE</version>    </dependency>    <dependency>      <groupId>junit</groupId>      <artifactId>junit</artifactId>      <version>4.6</version>    </dependency>  </dependencies>  <build>    <finalName>springmvc</finalName>  </build></project>