创建Web项目（Maven管理）

前言

开发工具：IDEA

1 创建项目

File > New > Module...

1.1 开发环境IDEA配置

设置maven配置

File > Settings > Build, Execution, Deployment > Build Tools > Maven

设置jdk版本

File > Project Structure

设置Tomcat

添加项目到Tomcat

1.2 pom.xml导入依赖

XML 复制代码

<?xml version="1.0" encoding="UTF-8"?>
<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>com.example</groupId>
    <artifactId>idea_maven</artifactId>
    <version>1.0-SNAPSHOT</version>

    <packaging>war</packaging>

    <dependencies>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-aop</artifactId>
            <version>5.3.10</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-beans</artifactId>
            <version>5.3.10</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-context</artifactId>
            <version>5.3.10</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-core</artifactId>
            <version>5.3.10</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-expression</artifactId>
            <version>5.3.10</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-jdbc</artifactId>
            <version>5.3.10</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-tx</artifactId>
            <version>5.3.10</version>
        </dependency>
        <!-- Spring MVC -->
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-webmvc</artifactId>
            <version>5.3.10</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-web</artifactId>
            <version>5.3.10</version>
        </dependency>
        <dependency>
            <groupId>commons-logging</groupId>
            <artifactId>commons-logging</artifactId>
            <version>1.2</version>
        </dependency>
        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>druid</artifactId>
            <version>1.2.9</version>
        </dependency>
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <version>1.18.42</version>
            <scope>compile</scope>
        </dependency>
        <dependency>
            <groupId>org.mybatis</groupId>
            <artifactId>mybatis</artifactId>
            <version>3.5.11</version>
        </dependency>
        <dependency>
            <groupId>org.mybatis</groupId>
            <artifactId>mybatis</artifactId>
            <version>3.5.11</version>
        </dependency>
        <dependency>
            <groupId>org.mybatis</groupId>
            <artifactId>mybatis-spring</artifactId>
            <version>1.3.1</version>
        </dependency>
        <dependency>
            <groupId>com.mysql</groupId>
            <artifactId>mysql-connector-j</artifactId>
            <version>8.0.32</version>
        </dependency>
        <dependency>
            <groupId>javax.servlet</groupId>
            <artifactId>javax.servlet-api</artifactId>
            <version>4.0.1</version>
            <scope>provided</scope>
        </dependency>
    </dependencies>
</project>

1.3 创建ServletAnnoInitConfig.java

（相当于web.xml）

java 复制代码

package com.example.config;

import javax.servlet.Filter;
import org.springframework.web.filter.CharacterEncodingFilter;
import org.springframework.web.servlet.support.AbstractAnnotationConfigDispatcherServletInitializer;
public class ServletAnnoInitConfig extends AbstractAnnotationConfigDispatcherServletInitializer{
    @Override
    protected Class<?>[] getRootConfigClasses() {
        return new Class[] {SpringConfig.class};
    }
    @Override
    protected Class<?>[] getServletConfigClasses() {
        return new Class[] {SpringMvcConfig.class};
    }
    @Override
    protected String[] getServletMappings() {
        return new String[]{"/"};
    }
}

1.4 创建SpringMvcConfig.java

（相当于springmvc-servlet.xml）

java 复制代码

package com.example.config;

import org.springframework.context.annotation.Configuration;

@Configuration
public class SpringMvcConfig {
}

1.5 创建SpringConfig.java

（相当于applicationContext.xml）

java 复制代码

package com.example.config;

import org.springframework.context.annotation.Configuration;

@Configuration
public class SpringConfig {
}

2 过滤器

ServletAnnoInitConfig.java

java 复制代码

    @Override
    protected Filter[] getServletFilters() {
        CharacterEncodingFilter filter = new CharacterEncodingFilter();
        filter.setEncoding("UTF-8");
        return new Filter[] {filter};
    }

3 拦截器

SpringMvcConfig.java

实现 WebMvcConfigurer接口

添加扫描注解 @ComponentScan(com.example.interceptor)

添加扫描注解 @EnableWebMvc// SpringMvcConfig内容生效

java 复制代码

package com.example.config;

import com.example.interceptor.ApiInterceptor;
import com.example.interceptor.LoginInterceptor;
import com.example.interceptor.PermissionInterceptor;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.annotation.ComponentScan;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.servlet.config.annotation.InterceptorRegistry;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurerAdapter;

@Configuration
@ComponentScan({"com.example.interceptor"})
@EnableWebMvc
public class SpringMvcConfig implements WebMvcConfigurer {
    @Autowired
    private ApiInterceptor apiInterceptor;
    @Autowired
    private LoginInterceptor loginInterceptor;
    @Autowired
    private PermissionInterceptor permissionInterceptor;

    @Override
    public void addInterceptors(InterceptorRegistry registry) {
        registry.addInterceptor(loginInterceptor).addPathPatterns("/&zwnj;**")
                .excludePathPatterns("/","/login"); //不拦截路径;
        registry.addInterceptor(permissionInterceptor)
                .addPathPatterns("/admin/**", "/user/**") // 拦截路径
                .excludePathPatterns("/user/login", "/user/register"); //不拦截路径
        registry.addInterceptor(apiInterceptor).addPathPatterns("/&zwnj;**"); // 参数用以来注入
    }
}

创建拦截器类

实现接口（HandlerInterceptor）或者继承类（HandlerInterceptorAdapter无需实现全部方法）

PermissionInterceptor

java 复制代码

package com.example.interceptor;

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

import org.springframework.stereotype.Component;
import org.springframework.web.servlet.handler.HandlerInterceptorAdapter;
@Component
public class PermissionInterceptor extends HandlerInterceptorAdapter {
    @Override
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response,
                             Object handler) throws Exception {
        response.getWriter().write("PermissionInterceptor Run");
        return true;
    }
}

LoginInterceptor

java 复制代码

package com.example.interceptor;

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

import org.springframework.stereotype.Component;
import org.springframework.web.servlet.HandlerInterceptor;
import org.springframework.web.servlet.ModelAndView;

@Component
public class LoginInterceptor implements HandlerInterceptor {
    
    @Override
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, 
                             Object handler) throws Exception {
        System.out.println("preHandle执行了");
        request.setAttribute("startTime", System.currentTimeMillis());
        Object user = request.getSession().getAttribute("user");
        if (user == null) {
            response.sendRedirect(request.getContextPath() + "/");
            return false; // 终止
        }
        
        return true; // 继续
    }
    
    @Override
    public void postHandle(HttpServletRequest request, HttpServletResponse response,
                           Object handler, ModelAndView modelAndView) throws Exception {
        System.out.println("postHandle执行了");
        if (modelAndView != null) {
            modelAndView.addObject("globalMsg", "请求成功");
        }
    }
    
    @Override
    public void afterCompletion(HttpServletRequest request, HttpServletResponse response,
                                Object handler, Exception ex) throws Exception {
        System.out.println("afterCompletion执行了");
        long startTime = (Long) request.getAttribute("startTime");
        long endTime = System.currentTimeMillis();
        System.out.println("运行时间" + (endTime - startTime) + "ms");
    }
}

ApiInterceptor

java 复制代码

package com.example.interceptor;

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

import org.springframework.beans.factory.annotation.Value;
import org.springframework.stereotype.Component;
import org.springframework.web.servlet.HandlerInterceptor;
import org.springframework.web.servlet.ModelAndView;

@Component
public class ApiInterceptor implements HandlerInterceptor {
    
    @Value("0:0:0:0:0:0:0:1")
    private String allowedIp;
    
    @Override
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response,
                             Object handler) throws Exception {
        String clientIp = request.getRemoteAddr();
        
        if (!allowedIp.equals(clientIp)) {
            response.setStatus(403);
            response.getWriter().write("Forbidden: IP not allowed");
            return false;
        }
        return true;
    }
    @Override
    public void afterCompletion(HttpServletRequest arg0, HttpServletResponse arg1, Object arg2, Exception arg3)
            throws Exception {
    }
    @Override
    public void postHandle(HttpServletRequest arg0, HttpServletResponse arg1, Object arg2, ModelAndView arg3)
            throws Exception {
    }
}

4 控制器

SpringMvcConfig.java （添加congroller扫描）

java 复制代码

package com.example.config;

import org.springframework.context.annotation.ComponentScan;
import org.springframework.context.annotation.Configuration;

@Configuration
@ComponentScan({"com.example.interceptor", "com.example.controller"})
@EnableWebMvc
public class SpringMvcConfig implements WebMvcConfigurer {

}

创建控制器类

LoginController

java 复制代码

package com.example.controller;		
		
import javax.servlet.http.HttpServletRequest;		
import javax.servlet.http.HttpServletResponse;		
		
import org.springframework.beans.factory.annotation.Autowired;		
import org.springframework.stereotype.Controller;		
import org.springframework.web.bind.annotation.RequestMapping;		
		
import com.example.pojo.User;		
import com.example.service.LoginService;		
		
@Controller		
public class LoginController{		
		
	@Autowired	
	private LoginService service;	
		
    @RequestMapping("/login")		
    public String login(HttpServletRequest req, HttpServletResponse res) throws Exception {		
    	String username = req.getParameter("user");	
        if (username == null || username.isEmpty()) {		
        	req.setAttribute("msg", "登录失败");	
            return "Login";		
        } 		
		
    	User user = service.getUser(username);	
    	if (user == null) {	
    		req.setAttribute("msg", "不存在用户");
        	return "Login";	
        } else {		
        	req.getSession().setAttribute("user", username);	
        	req.setAttribute("msg", "登录成功");	
            return "Home";		
        }		
    }		
		
}

LogoutController

java 复制代码

package com.example.controller;		
		
import javax.servlet.http.HttpServletRequest;		
import javax.servlet.http.HttpServletResponse;		
		
import org.springframework.stereotype.Controller;		
import org.springframework.web.bind.annotation.RequestMapping;		
		
@Controller		
public class LogoutController {		
		
	@RequestMapping("/logout")	
	public String logout(HttpServletRequest req, HttpServletResponse res) {	
		req.getSession().invalidate();
		req.setAttribute("msg", "登出成功");
		return "Login";
	}	
		
}

创建对应页面

src/main/webapp/WEB-INF/jsp/Login.jsp

html 复制代码

<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>Insert title here</title>
</head>
<body>
<%
  if(request.getAttribute("msg") != null){
%>
${msg}
<%
  }
%>
<br/>
登录页面Spring3.2<br/>
<form name="form1" action="/login" method="post">
    <input type="text" name="user" />
    <input type="password" name="password" />
    <button>登录</button>
</form>
</body>
</html>

src/main/webapp/WEB-INF/jsp/Home.jsp

html 复制代码

<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>
<!DOCTYPE html>
<html>
<head>
<meta charset="ISO-8859-1">
<title>Insert title here</title>
</head>
<body>
${msg}
<br/>
<form action="/logout" method="post">
  <button>logout</button>
</form>
</body>
</html>

5 数据库访问

连接数据库: mysql -hlocalhost -P3306 -uroot -proot

创建数据库: create database maven1;

切换数据库: use maven1;

创建数据库表: create table user(username varchar(20) primary key, password varchar(20) not null);

5.1 创建Mybatis配置类

MybatisConfig.java

java 复制代码

package com.example.config;
import org.mybatis.spring.mapper.MapperScannerConfigurer;
import org.springframework.context.annotation.Bean;
public class MybatisConfig {
    @Bean
    public MapperScannerConfigurer mapperScannerConfigurer(){
        MapperScannerConfigurer m = new MapperScannerConfigurer ();
        m.setBasePackage("com.example.mapper"); //扫描mapper包
        return m;
    }
}

5.2 业务逻辑代码

创建Model类

java 复制代码

package com.example.pojo;

import lombok.Data;

@Data    
public class User {
    private String username;
    private String password;
}

创建LoginMapper.java

java 复制代码

package com.example.mapper;

import java.util.List;

import org.apache.ibatis.annotations.Mapper;
import org.apache.ibatis.annotations.Param;

import com.example.pojo.User;

@Mapper
public interface LoginMapper {
    public User selectUserById(@Param("username") String username);
    public List<User> selectAllUsers();
    public int insertUser(User user);
    public int updateUser(User user);
    public int deleteUser(@Param("username") String username);
}

创建LoginMapper.xml

XML 复制代码

src/main/resources/com/example/mapper/UserMapper.xml

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
  "http://mybatis.org/dtd/mybatis-3-mapper.dtd">

<mapper namespace="com.example.mapper.LoginMapper">

    <!-- 查询用户ById -->
    <select id="selectUserById" resultType="com.example.pojo.User">
        SELECT username, password
        FROM user
        WHERE username = #{username}
    </select>

    <!-- 查询所有用户 -->
    <select id="selectAllUsers" resultType="list">
        SELECT username, password
        FROM user
        ORDER BY username ASC
    </select>

    <!-- 插入新用户 -->
    <insert id="insertUser" parameterType="com.example.pojo.User" >
        INSERT INTO user (username, password)
        VALUES (#{username}, #{password})
    </insert>

    <!-- 更新用户信息 -->
    <update id="updateUser" parameterType="com.example.pojo.User">
        UPDATE user
        SET username = #{username},
            password = #{password}
        WHERE username = #{username}
    </update>

    <!-- 删除用户 -->
    <delete id="deleteUser" parameterType="long">
        DELETE FROM user WHERE username = #{username}
    </delete>
</mapper>

创建LoginService

java 复制代码

package com.example.service;		
		
import org.springframework.beans.factory.annotation.Autowired;		
import org.springframework.stereotype.Service;		
import org.springframework.transaction.annotation.Transactional;		
		
import com.example.mapper.LoginMapper;		
import com.example.pojo.User;		
		
@Service		
@Transactional		
public class LoginService {		
	@Autowired	
	private LoginMapper dao;	
	public User getUser(String username) {	
		return dao.selectUserById(username);
	}	
}

5.3 SpringConfig.java添加配置

创建数据库连接信息（resources/jdbc.properties）

java 复制代码

jdbc.driver=com.mysql.cj.jdbc.Driver
jdbc.url=jdbc:mysql://localhost:3306/maven1
jdbc.username=root
jdbc.password=root

创建JdbcConfig.java

java 复制代码

package com.example.config;

import org.springframework.beans.factory.annotation.Value;
import org.springframework.context.annotation.Bean;
import org.springframework.jdbc.datasource.DataSourceTransactionManager;
import org.springframework.transaction.PlatformTransactionManager;

import com.alibaba.druid.pool.DruidDataSource;

public class JdbcConfig {
    
    @Value("${jdbc.driver}")
    private String driver;
    
    @Value("${jdbc.url}")
    private String url;
    
    @Value("${jdbc.username}")
    private String username;
    
    @Value("${jdbc.password}")
    private String password;
    // 配置数据源
    @Bean    
    public DruidDataSource druidDataSource() {    
        DruidDataSource d = new DruidDataSource();
        d.setDriverClassName(driver);
        d.setUrl(url);
        d.setUsername(username);
        d.setPassword(password);
        return d;

    }
    // 配置事务控制
    @Bean    
    public PlatformTransactionManager transactionManager(DruidDataSource datasource) {    
        DataSourceTransactionManager ds = new DataSourceTransactionManager();
        ds.setDataSource(datasource);
        return ds;
    }

}

SpringConfig.java添加扫描

java 复制代码

package com.example.config;				
				
import org.springframework.context.annotation.Configuration;				
import org.springframework.context.annotation.Import;				
import org.springframework.context.annotation.PropertySource;				
import org.springframework.transaction.annotation.EnableTransactionManagement;				
				
@Configuration				
@PropertySource("classpath:jdbc.properties") // 加载properties文件
@Import({JdbcConfig.class})				     // 导入数据源实现类
@EnableTransactionManagement				 // 启动事务管理注解
public class SpringConfig {				
				
}

5.4 整合mybatis

MybatisConfig.java

java 复制代码

package com.example.config;		
		
import org.mybatis.spring.SqlSessionFactoryBean;		
import org.mybatis.spring.mapper.MapperScannerConfigurer;		
import org.springframework.context.annotation.Bean;		
		
import com.alibaba.druid.pool.DruidDataSource;		
		
public class MybatisConfig {		
	@Bean	
	public SqlSessionFactoryBean sqlSessionFactory(DruidDataSource ds){	
		SqlSessionFactoryBean b = new SqlSessionFactoryBean();
		b.setTypeAliasesPackage("com.example.pojo"); //用于自动类型转换
		b.setDataSource(ds);
		return b;
	}	
		
	@Bean	
	public MapperScannerConfigurer mapperScannerConfigurer(){	
		MapperScannerConfigurer m = new MapperScannerConfigurer ();
		m.setBasePackage("com.example.mapper"); //扫描mapper包
		return m;
	}	
}

5.5 扫描Bean

SpringConfig.java

java 复制代码

package com.example.config;

import org.springframework.context.annotation.ComponentScan;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.Import;
import org.springframework.context.annotation.PropertySource;
import org.springframework.transaction.annotation.EnableTransactionManagement;

@Configuration
@ComponentScan({"com.example.service"})
@PropertySource("jdbc.properties")
@Import({JdbcConfig.class, MybatisConfig.class})
@EnableTransactionManagement
public class SpringConfig {
}

6 视图

6.1 视图解析器

SpringMvcConfig.java

java 复制代码

    @Override
    public void configureViewResolvers(ViewResolverRegistry registry) {
        registry.jsp("/WEB-INF/jsp/", ".jsp");
    }

6.2 视图控制器

SpringMvcConfig.java

java 复制代码

    @Override
    public void addViewControllers(ViewControllerRegistry registry) {
        registry.addViewController("/").setViewName("Login");
    }

7 扩展功能

静态资源访问

SpringMvcConfig.java

java 复制代码

    @Override
    public void addResourceHandlers(ResourceHandlerRegistry registry) {
        registry.addResourceHandler("/css/**")  // 满足条件请求不走拦截器
                .addResourceLocations("/WEB-INF/css/"); //走指定的资源访问
    }

新建css样式

/WEB-INF/css/sytle.css

java 复制代码

body {	
	color: blue;
}

html 复制代码

<link rel="stylesheet" href="../css/style.css">

启动服务器

(1) 首页访问

(2) 登录

(3) 错误用户名登录

(4) 正确用户名登录

(5) 登出

IDEA启动Tomcat控制台乱码解决

Help > Edit Custom VM Options（文件末尾添加 -Dfile.encoding=UTF-8，重启 IDEA）

Run > Edit Configurations，在 Tomcat Server 的 VM options 中添加-Dfile.encoding=UTF-8