SpringMVC 登录验证实例

1、pom.xml中加入SpringMVC的依赖

<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/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <groupId>SSM06</groupId>
    <artifactId>SSM06</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <packaging>war</packaging>
    <build>
        <sourceDirectory>src</sourceDirectory>
        <plugins>
            <plugin>
                <artifactId>maven-compiler-plugin</artifactId>
                <version>3.5.1</version>
                <configuration>
                    <source>1.8</source>
                    <target>1.8</target>
                </configuration>
            </plugin>
            <plugin>
                <artifactId>maven-war-plugin</artifactId>
                <version>3.0.0</version>
                <configuration>
                    <warSourceDirectory>WebContent</warSourceDirectory>
                </configuration>
            </plugin>
        </plugins>
    </build>
    <dependencies>
        <!--         mybatis依赖 -->
        <dependency>
            <groupId>org.mybatis</groupId>
            <artifactId>mybatis</artifactId>
            <version>3.3.1</version>
        </dependency>
        <!--         数据库连接池 -->
        <dependency>
            <groupId>org.apache.commons</groupId>
            <artifactId>commons-dbcp2</artifactId>
            <version>2.1.1</version>
        </dependency>
        <!--         spring的依赖 -->
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-context</artifactId>
            <version>4.1.9.RELEASE</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-webmvc</artifactId>
            <version>4.1.9.RELEASE</version>
        </dependency>
        <dependency>
            <groupId>org.mybatis</groupId>
            <artifactId>mybatis-spring</artifactId>
            <version>1.3.1</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-jdbc</artifactId>
            <version>4.1.9.RELEASE</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-aspects</artifactId>
            <version>4.1.9.RELEASE</version>
        </dependency>
        <!--         标准标签库 -->
        <dependency>
            <groupId>javax.servlet</groupId>
            <artifactId>jstl</artifactId>
            <version>1.2</version>
        </dependency>
        <!-- 对json数据的支持jar -->
        <dependency>
            <groupId>com.fasterxml.jackson.core</groupId>
            <artifactId>jackson-databind</artifactId>
            <version>2.8.10</version>
        </dependency>
        <dependency>
            <groupId>com.fasterxml.jackson.core</groupId>
            <artifactId>jackson-core</artifactId>
            <version>2.8.10</version>
        </dependency>
        <dependency>
            <groupId>com.fasterxml.jackson.core</groupId>
            <artifactId>jackson-annotations</artifactId>
            <version>2.8.10</version>
        </dependency>
    </dependencies>
</project>

2、web.xml中加入SpringMVC的核心拦截器，并指向其核心配置文件spring-mvc.xml

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://xmlns.jcp.org/xml/ns/javaee" xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_3_1.xsd" id="WebApp_ID" version="3.1">
  <display-name>SSM06</display-name>
      <listener>
        <description>spring监听器</description>
        <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
    </listener>    
    <context-param>
        <param-name>contextConfigLocation</param-name>
        <param-value>classpath:spring-mvc.xml</param-value>
    </context-param>

    <!--     spring提供的字符集的过滤器 -->
    <filter>
        <filter-name>encodingFilter</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>encodingFilter</filter-name>
        <url-pattern>/*</url-pattern>
    </filter-mapping>

    <!--   springmvc的核心拦截器是一个servlet -->
    <servlet>
        <servlet-name>springmvc</servlet-name>
        <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
        <init-param>
            <param-name>contextConfigLocation</param-name>
            <param-value>classpath:spring-mvc.xml</param-value>
        </init-param>
        <!-- 加载优先级,越小越优先 -->
        <load-on-startup>1</load-on-startup>
     </servlet>
    <servlet-mapping>
        <servlet-name>springmvc</servlet-name>
        <url-pattern>/</url-pattern>
    </servlet-mapping>

    <welcome-file-list>
        <welcome-file>index.html</welcome-file>
        <welcome-file>index.htm</welcome-file>
        <welcome-file>index.jsp</welcome-file>
        <welcome-file>default.html</welcome-file>
        <welcome-file>default.htm</welcome-file>
        <welcome-file>default.jsp</welcome-file>
     </welcome-file-list>
</web-app>

3、创建spring-mvc.xml核心配置文件

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
    xmlns:mvc="http://www.springframework.org/schema/mvc" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xmlns:p="http://www.springframework.org/schema/p" xmlns:context="http://www.springframework.org/schema/context"
    xsi:schemaLocation="http://www.springframework.org/schema/beans 
http://www.springframework.org/schema/beans/spring-beans.xsd 
http://www.springframework.org/schema/context 
http://www.springframework.org/schema/context/spring-context.xsd 
http://www.springframework.org/schema/mvc 
http://www.springframework.org/schema/mvc/spring-mvc.xsd">

    <!-- 自动扫描controller包下的所有类，使其认为spring mvc的控制器 -->
    <context:component-scan base-package="com" />
    <!--spring对注解的支持 这个配置和  <mvc:annotation-driven /> 是同一个意思，只不过是来自于不同的包 -->
    <!-- <context:annotation-config></context:annotation-config> -->

    <!-- 对模型视图名称的解析，即在模型视图名称添加前后缀 -->
    <bean
        class="org.springframework.web.servlet.view.InternalResourceViewResolver"
        p:prefix="/" p:suffix=".jsp" />
    
    <!-- 让springmvc放过对静态资源的拦截 -->
    <mvc:annotation-driven /> 
    <mvc:resources location="/js/" mapping="/js/**"></mvc:resources>
    <mvc:resources location="/css/" mapping="/css/**"></mvc:resources>
    <mvc:resources location="/img/" mapping="/img/**"></mvc:resources>

    <!-- 对josn数据的支持 -->
    <bean id="jsonConverter"
        class="org.springframework.http.converter.json.MappingJackson2HttpMessageConverter"></bean>
    <bean id="stringConverter"
        class="org.springframework.http.converter.StringHttpMessageConverter">
        <property name="supportedMediaTypes">
            <list>
                <value>text/plain;charset=UTF-8</value>
            </list>
        </property>
    </bean>
    <bean
        class="org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter">
        <property name="messageConverters">
            <list>
                <ref bean="stringConverter" />
                <ref bean="jsonConverter" />
            </list>
        </property>
    </bean>
</beans>

4、创建User.java用户实体类+LoginController.java登录控制器

　　User.java

package com.pojo;

public class User {
    String username;
    String pwd;
    public String getUsername() {
        return username;
    }
    public void setUsername(String username) {
        this.username = username;
    }
    public String getPwd() {
        return pwd;
    }
    public void setPwd(String pwd) {
        this.pwd = pwd;
    }
    
}

　　LoginController.jva

package com.controller;

import javax.servlet.http.HttpServletRequest;

import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;

import com.pojo.User;

@Controller
public class LoginController {

    @RequestMapping("/login")
    public String login(User user,HttpServletRequest req){
        System.out.println(user.getUsername());
        System.out.println(req.getRequestURI());
        return "redirect:success";//默认是转发
    }
}

5、创建登录页面login.jsp+登录成功提示页面success.jsp

　　login.jsp

<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>
<%
    String path = request.getContextPath();
    String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";
%>
<!DOCTYPE html>
<html>
<head>
<base href="<%=basePath%>"/>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Insert title here</title>
</head>
<body>
    <form action="login" method="post">
        用户名：<input name="username"><br>
        密码：<input type="password" name="pwd"><br>
        <input type="submit" value="登录">
    </form>
</body>
</html>

　　success.jsp

<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>
<%
    String path = request.getContextPath();
    String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";
%>
<!DOCTYPE html>
<html>
<head>
<base href="<%=basePath%>"/>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Insert title here</title>
</head>
<body>
    欢迎登录
</body>
</html>

6、在tomcat下运行该项目，打开登录页面，输入用户名、密码进行登录验证。