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IDEA整合SSM框架
- 2023年07月06日
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2023-07-06
创建项目打开IDEA-File-Project项目大致目录项目目录类型修改pom.xml添加maven依赖 <properties>  <maven.compiler.source>1.8</maven.compiler.source> <maven.compiler.target>1.8</maven.compiler.target> <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding> <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>  <spring.version>4.3.5.RELEASE</spring.version>  <mybatis.version>3.4.1</mybatis.version> </properties> <dependencies> <dependency> <groupId>javax.servlet</groupId> <artifactId>jstl</artifactId> <version>1.2</version> </dependency> <dependency> <groupId>org.apache.taglibs</groupId> <artifactId>taglibs-standard-impl</artifactId> <version>1.2.5</version> </dependency>  <dependency> <groupId>org.slf4j</groupId> <artifactId>slf4j-api</artifactId> <version>1.7.30</version> </dependency> <dependency> <groupId>ch.qos.logback</groupId> <artifactId>logback-classic</artifactId> <version>1.2.2</version> </dependency> <dependency> <groupId>ch.qos.logback</groupId> <artifactId>logback-core</artifactId> <version>1.2.3</version> </dependency>  <dependency> <groupId>com.fasterxml.jackson.core</groupId> <artifactId>jackson-databind</artifactId> <version>2.8.7</version> </dependency>  <dependency> <groupId>mysql</groupId> <artifactId>mysql-connector-java</artifactId> <version>8.0.25</version> <scope>runtime</scope> </dependency>  <dependency> <groupId>com.mchange</groupId> <artifactId>c3p0</artifactId> <version>0.9.5.2</version> </dependency>  <dependency> <groupId>org.mybatis</groupId> <artifactId>mybatis</artifactId> <version>${mybatis.version}</version> </dependency>  <dependency> <groupId>org.mybatis</groupId> <artifactId>mybatis-spring</artifactId> <version>1.3.1</version> </dependency>  <dependency> <groupId>org.springframework</groupId> <artifactId>spring-core</artifactId> <version>${spring.version}</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-beans</artifactId> <version>${spring.version}</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-context</artifactId> <version>${spring.version}</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-jdbc</artifactId> <version>${spring.version}</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-tx</artifactId> <version>${spring.version}</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-web</artifactId> <version>${spring.version}</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-webmvc</artifactId> <version>${spring.version}</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-test</artifactId> <version>${spring.version}</version> </dependency> <dependency> <groupId>junit</groupId> <artifactId>junit</artifactId> <version>3.8.1</version> <scope>test</scope> </dependency> </dependencies> <build> <finalName>spring-ssm</finalName> </build>配置DispatcherServlet有关DispatcherServlet前端控制器的文章可以查看SpringMVC之DispatcherServlet前置控制器编辑web.xml<!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> <display-name>ssm</display-name>  <filter>  <filter-name>SetCharacterEncoding</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>  <init-param> <param-name>forceEncoding</param-name> <param-value>true</param-value> </init-param> </filter>  <filter-mapping>  <filter-name>SetCharacterEncoding</filter-name>  <url-pattern>/*</url-pattern> </filter-mapping>  <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-*.xml</param-value> </init-param> <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.jsp</welcome-file> </welcome-file-list> </web-app> 在这里提一嘴，很多同学不太明白拦截器和过滤器的区别，现在跟大家解释一下两者的区别：拦截器是基于Java的反射机制的，而过滤器则是基于函数的回调拦截器是实现HandleInterceptor，过滤器则是实现Filter接口拦截器不依赖于Servlet容器，过滤器依赖于Servlet容器拦截器使用来验证请求，能截断请求。过滤器用来设置request，response参数、属性，侧重对数据的过滤过滤器在拦截器之前执行过滤器是tomcat服务器创建的对象，拦截器是springmvc容器创建的对象过滤器可以处理jsp、js、html等；拦截器是侧重拦截Controller的对象，如果你的请求不能被DispatcherServlet接收，这个请求不会执行拦截器的内容拦截器可以获取IOC容器中的各个bean，而过滤器就不行，这点很重要，在拦截器里注入一个service，可以调用业务逻辑配置SpringMVC在classpath目录下也就是resources目录下新增spring-mvc.xml配置文件，写入：<?xml version="1.0" encoding="UTF-8"?> <beans xmlns="http://www.springframework.org/schema/beans" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:context="http://www.springframework.org/schema/context" xmlns:mvc="http://www.springframework.org/schema/mvc" 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 ">  <context:component-scan base-package="com.bystart.ssm.controller"/>  <mvc:annotation-driven/>  <mvc:default-servlet-handler/>  <bean class="org.springframework.web.servlet.view.InternalResourceViewResolver"> <property name="viewClass" value="org.springframework.web.servlet.view.JstlView"/> <property name="prefix" value="/WEB-INF/views/"/> <property name="suffix" value=".jsp"/> </bean> </beans>集成MySQL、MyBatis同样是是在resources目录下，首先先创建mysql的连接配置文件jdbc.propertiesjdbc.driver=com.mysql.jdbc.Driver #数据库地址 jdbc.url=jdbc:mysql://127.0.0.1:3306/ssmdb?useUnicode=true&characterEncoding=utf8&useSSL=false #用户名 jdbc.username=root #密码 jdbc.password=123456 #最大连接数 c3p0.maxPoolSize=30 #最小连接数 c3p0.minPoolSize=10 #关闭连接后不自动commit c3p0.autoCommitOnClose=false #获取连接超时时间 c3p0.checkoutTimeout=10000 #当获取连接失败重试次数 c3p0.acquireRetryAttempts=2继续添加spring-mybatis.xml：<?xml version="1.0" encoding="UTF-8"?> <beans xmlns="http://www.springframework.org/schema/beans" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:context="http://www.springframework.org/schema/context" xmlns:tx="http://www.springframework.org/schema/tx" 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/tx http://www.springframework.org/schema/tx/spring-tx.xsd">   <context:property-placeholder location="classpath:jdbc.properties"/>  <bean id="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource"> <property name="driverClass" value="${jdbc.driver}"/> <property name="jdbcUrl" value="${jdbc.url}"/> <property name="user" value="${jdbc.username}"/> <property name="password" value="${jdbc.password}"/> <property name="maxPoolSize" value="${c3p0.maxPoolSize}"/> <property name="minPoolSize" value="${c3p0.minPoolSize}"/> <property name="autoCommitOnClose" value="${c3p0.autoCommitOnClose}"/> <property name="checkoutTimeout" value="${c3p0.checkoutTimeout}"/> <property name="acquireRetryAttempts" value="${c3p0.acquireRetryAttempts}"/> </bean>  <bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">  <property name="dataSource" ref="dataSource"/>  <property name="typeAliasesPackage" value="com.bystart.ssm.model"/>  <property name="mapperLocations" value="classpath:mapper/*.xml"/> </bean>  <bean id="transactionManager" class="org.springframework.jdbc.datasource.DataSourceTransactionManager">  <property name="dataSource" ref="dataSource"/> </bean>  <tx:annotation-driven transaction-manager="transactionManager"/>  <bean class="org.mybatis.spring.mapper.MapperScannerConfigurer">  <property name="sqlSessionFactoryBeanName" value="sqlSessionFactory"/>  <property name="basePackage" value="com.bystart.ssm.dao"/> </bean>  <context:component-scan base-package="com.bystart.ssm.dao"/>  <context:component-scan base-package="com.bystart.ssm.service"/> </beans> 添加日志输出新增logback-spring.xml同样是在resources目录下<?xml version="1.0" encoding="UTF-8"?> <configuration debug="true"> <appender name="STDOUT" class="ch.qos.logback.core.ConsoleAppender"> <encoder> <pattern>%d{HH:mm:ss.SSS} [%thread] %-5level %logger{36} - %msg%n</pattern> </encoder> </appender> <root level="debug"> <appender-ref ref="STDOUT"/> </root> </configuration>实战从数据库查询数据数据库表结构：CREATE TABLE `sys_user` ( `id` bigint NOT NULL AUTO_INCREMENT COMMENT '主键', `username` varchar(32) NOT NULL COMMENT '用户名', `password` varchar(32) NOT NULL COMMENT '密码', PRIMARY KEY (`id`) ) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_0900_ai_ci;插入数据：INSERT INTO `sys_user` (`id`, `username`, `password`) VALUES (1, 'sysadmin', '123456');编写数据表对应的JavaBean在包路径com.bystart.ssm.model下创建数据库表对应的Java类实体package com.bystart.ssm.model; public class SysUserEntity { /** * 自增id */ private Long id; /** * 用户名 */ private String username; /** * 密码 */ private String password; public SysUserEntity() { } public SysUserEntity(Long id, String username, String password) { this.id = id; this.username = username; this.password = password; } public Long getId() { return id; } public void setId(Long id) { this.id = id; } public String getUsername() { return username; } public void setUsername(String username) { this.username = username; } public String getPassword() { return password; } public void setPassword(String password) { this.password = password; } @Override public String toString() { return "SysUserEntity{" + "id=" + id + ", username='" + username + '\'' + ", password='" + password + '\'' + '}'; } }编写数据交互层DAO在包com.bystart.ssm.dao路径下添加接口package com.bystart.ssm.dao; import com.bystart.ssm.model.SysUserEntity; import org.apache.ibatis.annotations.Param; import org.springframework.stereotype.Repository; import java.util.List; public interface SysUserDao{ /** * 查询所有的用户 * */ List<SysUserEntity> getUserList(); /** * 根据用户名查询指定用户 * */ SysUserEntity getUserByUsername(@Param("username") String username); }编写SysUserDao.xml在resources-mapper目录下新增SysUserDao.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.bystart.ssm.dao.SysUserDao"> <select id="getUserList" resultType="com.bystart.ssm.model.SysUserEntity"> select * from sys_user </select> <select id="getUserByUsername" resultType="com.bystart.ssm.model.SysUserEntity"> select * from sys_user where username = #{username} </select> </mapper>编写业务层接口在com.bystart.ssm.service新增SysUserService接口，并提供两个方法package com.bystart.ssm.service; import com.bystart.ssm.model.SysUserEntity; import java.util.List; public interface SysUserService { /** * 查询所有的用户 * */ List<SysUserEntity> getUserList(); /** * 根据用户名查询用户的信息 * @param username 用户名查询条件 * */ SysUserEntity getUserByUsername(String username); }添加service的实现类，在com.bystart.ssm.service.impl包下新增SysUserServiceImpl实现类package com.bystart.ssm.service.impl; import com.bystart.ssm.dao.SysUserDao; import com.bystart.ssm.model.SysUserEntity; import com.bystart.ssm.service.SysUserService; import org.springframework.stereotype.Service; import javax.annotation.Resource; import java.util.List; @Service public class SysUserServiceImpl implements SysUserService { @Resource private SysUserDao dao; @Override public List<SysUserEntity> getUserList() { return dao.getUserList(); } @Override public SysUserEntity getUserByUsername(String username) { return dao.getUserByUsername(username); } }编写controllercom.bystart.ssm.controller包下新增SysUserControllerpackage com.bystart.ssm.controller; import com.bystart.ssm.model.SysUserEntity; import com.bystart.ssm.service.SysUserService; 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.bind.annotation.ResponseBody; import javax.annotation.Resource; import java.util.List; @Controller public class SysUserController { @Resource private SysUserService service; /** * 查询用户列表并返回到JSP进行数据渲染 */ @RequestMapping("/getUserList") public String getUserList(Model model) { List<SysUserEntity> userList = service.getUserList(); model.addAttribute("userList", userList); // 返回到 webapp目录下的 WEB-INF > views > userList.jsp return "userList"; } /** * 根据用户名查询指定用户 * 将查询到的数据以json形式返回到页面 * * @param username 用户名 */ @RequestMapping("/getUserByUsername") @ResponseBody public SysUserEntity getUserByUsername(@RequestParam String username) { SysUserEntity user = service.getUserByUsername(username); return user; } }编写JSP页面在webapp -> WEB-INF -> views目录下新增userList.jsp：<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %> <%-- Created by IntelliJ IDEA. User: bystart Date: 2023/7/6 Time: 15:32 To change this template use File | Settings | File Templates. --%> <%@ page contentType="text/html;charset=UTF-8" language="java" isELIgnored="false" %> <html> <head> <title>Title</title> </head> <body> <table border=1> <thead> <tr> <th>序号</th> <th>用户名</th> <th>密码</th> </tr> </thead> <tbody> <c:forEach items="${userList}" var="user"> <tr> <th>${user.id}</th> <th>${user.username}</th> <th>${user.password}</th> </tr> </c:forEach> </tbody> </table> </body> </html>配置tomcat配置好tomcat后即可运行起来测试发起请求获得数据我们编写的SysUserController中有两个接口，一个会返回页面，一个会返回json数据我们在浏览器中请求http://localhost:8080/ssm/此处的地址可以在这里查看在浏览器访问http://localhost:8080/ssm/getUserList再去访问http://localhost:8080/ssm/getUserByUsername?username=sysadmin如果能跟我一样正常显示，说明ssm框架搭建完成，并且可以跟数据库进行交互