基于IDEA 2019 + jdk 1.8 + maven 3.6.3搭建SSM项目

创建项目

项目结构目录

上图的项目结构，看到的配置的文件比较多，在配置中出问题很正常，需要耐心配置。亲测项目可以运行，后面跟大家展示效果！！

• 配置pom.xml文件添加相关依赖
• 配置web.xml
• 配置jdbc.properties
• 配置Spring-mybatis.xml
• 配置Spring-mvc.xml
• 配置mybatis-config.xml

pom.xml依赖配置
下载依赖非常慢的话，需要配置一下maven conf文件的setting.xml，默认下载的是国外网站的jar包。setting.xml配置解决下载慢的教程

<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.ssm</groupId><artifactId>ssm</artifactId><packaging>war</packaging><version>1.0-SNAPSHOT</version><name>ChatRobot Maven Webapp</name><url>http://maven.apache.org</url><properties><!-- 设置项目编码编码 --><project.build.sourceEncoding>UTF-8</project.build.sourceEncoding><project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding><!-- spring版本号 --><spring.version>4.3.5.RELEASE</spring.version><!-- mybatis版本号 --><mybatis.version>3.4.1</mybatis.version></properties><dependencies><!-- java ee --><dependency><groupId>javax</groupId><artifactId>javaee-api</artifactId><version>7.0</version></dependency><!-- 单元测试 --><dependency><groupId>junit</groupId><artifactId>junit</artifactId><version>4.12</version></dependency><!-- 实现slf4j接口并整合 --><dependency><groupId>ch.qos.logback</groupId><artifactId>logback-classic</artifactId><version>1.2.2</version></dependency><!-- JSON --><dependency><groupId>com.fasterxml.jackson.core</groupId><artifactId>jackson-databind</artifactId><version>2.8.7</version></dependency><!-- 数据库 --><dependency><groupId>mysql</groupId><artifactId>mysql-connector-java</artifactId><version>5.1.41</version><scope>runtime</scope></dependency><!-- 数据库连接池 --><dependency><groupId>com.mchange</groupId><artifactId>c3p0</artifactId><version>0.9.5.2</version></dependency><!-- MyBatis --><dependency><groupId>org.mybatis</groupId><artifactId>mybatis</artifactId><version>${mybatis.version}</version></dependency><!-- mybatis/spring整合包 --><dependency><groupId>org.mybatis</groupId><artifactId>mybatis-spring</artifactId><version>1.3.1</version></dependency><!-- Spring --><dependency><groupId>org.springframework</groupId><artifactId>spring-core</artifactId><version>${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></dependencies><build><finalName>SpringMVC_ssm</finalName><plugins><plugin><groupId>org.apache.maven.plugins</groupId><artifactId>maven-compiler-plugin</artifactId><configuration><!-- 设置JDK版本 --><source>1.8</source><target>1.8</target></configuration></plugin></plugins></build></project>

Jar包列表，都已经下载好了，并且存放到项目中

web.xml配置

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns="http://xmlns.jcp.org/xml/ns/javaee"xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_3_1.xsd"version="3.1"><welcome-file-list><welcome-file>index.html</welcome-file></welcome-file-list><!-- 编码过滤器 --><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><!-- 配置DispatcherServlet --><servlet><servlet-name>SpringMVC</servlet-name><servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class><!-- 配置springMVC需要加载的配置文件--><init-param><param-name>contextConfigLocation</param-name><param-value>classpath:spring-*.xml</param-value></init-param><load-on-startup>1</load-on-startup><async-supported>true</async-supported></servlet><servlet-mapping><servlet-name>SpringMVC</servlet-name><!-- 匹配所有请求，此处也可以配置成 *.do 形式 --><!--/*.do是对所有以.do结尾的请求做处理，/*是对所有请求做处理--><url-pattern>/*</url-pattern></servlet-mapping>
</web-app>

Spring-mvc.xml配置

<?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/beanshttp://www.springframework.org/schema/beans/spring-beans.xsdhttp://www.springframework.org/schema/contexthttp://www.springframework.org/schema/context/spring-context.xsdhttp://www.springframework.org/schema/mvchttp://www.springframework.org/schema/mvc/spring-mvc-3.0.xsd"><!-- 扫描web相关的bean --><context:component-scan base-package="cn.wg.controller"/><!-- 开启SpringMVC注解模式 --><mvc:annotation-driven/><!-- 静态资源默认servlet配置 --><mvc:default-servlet-handler/><!-- 配置jsp 显示ViewResolver --><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>

jdbc.properties配置

jdbc.driver=com.mysql.jdbc.Driver
jdbc.url=jdbc:mysql://127.0.0.1:3308/girls?characterEncoding=utf-8
jdbc.username=root
jdbc.password=dream

Spring-mybatis.xml配置并且读取jdbc.properties配置文件的属性值

<?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/beanshttp://www.springframework.org/schema/beans/spring-beans.xsdhttp://www.springframework.org/schema/contexthttp://www.springframework.org/schema/context/spring-context.xsdhttp://www.springframework.org/schema/txhttp://www.springframework.org/schema/tx/spring-tx.xsd"><!-- 扫描service包下所有使用注解的类型 --><context:component-scan base-package="cn.wg.service"/><!-- 关联数据库属性文件--><context:property-placeholder location="classpath:jdbc.properties" /><!-- 01.数据库连接池 配置数据源 --><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}"/></bean><!-- 02.配置SessionFactory --><bean id="sessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean"><!-- 扫描entity包 使用别名 --><property name="typeAliasesPackage" value="cn.wg.entity"/><property name="dataSource" ref="dataSource"></property><!-- 扫描sql配置文件:mapper需要的xml文件 --><property name="mapperLocations" value="classpath:mapper/*.xml"/></bean><!-- 03.生成dao代理對象 --><bean class="org.mybatis.spring.mapper.MapperScannerConfigurer"><!-- 注入sqlSessionFactory --><property name="sqlSessionFactoryBeanName" value="sessionFactory"></property><!-- 给出需要扫描Dao接口包 --><property name="basePackage" value="cn.wg.dao"></property></bean><!-- 配置事务管理器 --><bean id="transactionManager" class="org.springframework.jdbc.datasource.DataSourceTransactionManager"><!-- 注入数据库连接池 --><property name="dataSource" ref="dataSource"/></bean><!-- 配置基于注解的声明式事务 --><tx:annotation-driven transaction-manager="transactionManager"/></beans>

配置mybatis-config.xml文件

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE configurationPUBLIC "-//mybatis.org//DTD Config 3.0//EN""http://mybatis.org/dtd/mybatis-3-config.dtd">
<configuration><typeAliases><package name="cn.wg.entity"/></typeAliases><mappers><package name="cn.wg.dao"/></mappers>
</configuration>

配置文件都配完了，接下来编写mybatis mapper映射的SQL语句的GirlDao.xml文件

<?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"><!-- 设置为GirlDao接口方法提供sql语句配置 -->
<mapper namespace="cn.wg.dao.GirlDao"><select id="findOne" resultType="Girl" parameterType="int">SELECT * FROM Girl WHERE id = #{id}</select><delete id="delete"  parameterType="int">DELETE FROM Girl  WHERE id = #{id}</delete><insert id="insert" parameterType="Girl">INSERT INTO Girl(id,name,age) values (#{id},#{name},#{age})</insert><update id="update" parameterType="Girl">UPDATE Girl set name=#{name},age=#{age} WHERE id=#{id}</update>
</mapper>

dao接口实现增删改查，在service使用dao接口提供方法Girl findOne(int id),这接口并没有实现具体方法，其实它映射到Mybatis mapper GirlDao.xml执行id为findOne 的sql语句

package cn.wg.dao;import cn.wg.entity.Girl;public interface GirlDao {Girl findOne(int id);void delete(int id);void update(Girl girl);Girl insert(Girl girl);
}

实体类
类属性名称要跟数据库表里面的字段属性名称一致

package cn.wg.entity;public class Girl {private Integer id;private String name;private Integer age;public Integer getId() {return id;}public void setId(Integer id) {this.id = id;}public String getName() {return name;}public void setName(String name) {this.name = name;}public Integer getAge() {return age;}public void setAge(Integer age) {this.age = age;}
}

service接口和service类

package cn.wg.service;import cn.wg.entity.Girl;public interface GirlService {Girl findOne(int id);
}

package cn.wg.service.impl;import cn.wg.dao.GirlDao;
import cn.wg.entity.Girl;
import cn.wg.service.GirlService;
import org.springframework.stereotype.Service;import javax.annotation.Resource;@Service
public class GirlServiceImpl implements GirlService {@Resourceprivate GirlDao girlDAO;@Overridepublic Girl findOne(int id) {System.out.println("---------11----------------");Girl girl = girlDAO.findOne(id);if (girl == null) {System.out.println("此id不存在！！！");return null;}return girl;} 
}

controller层

package cn.wg.controller;import cn.wg.entity.Girl;
import cn.wg.service.GirlService;
import cn.wg.util.ResultVOUtil;
import cn.wg.vo.ResultVO;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.*;
import javax.annotation.Resource;@Controller
@RequestMapping("/girl")
public class GirlController {@Resourceprivate GirlService girlService;@RequestMapping("/find/{id}")@ResponseBody@CrossOrigin(origins="*",maxAge=3600)//跨域，实现浏览器可以访问此接口public ResultVO findOneGirl(@PathVariable("id") Integer id) {System.out.println("----------------22----------------------------------");Girl girl = girlService.findOne(id);return ResultVOUtil.convert(200,"success",girl);}   
}

ResultVO类传给前端的视图数据

package cn.wg.vo;import com.fasterxml.jackson.annotation.JsonProperty;public class ResultVO<T> {private Integer code;private String msg;@JsonProperty("girl")private T data;public Integer getCode() {return code;}public void setCode(Integer code) {this.code = code;}public String getMsg() {return msg;}public void setMsg(String msg) {this.msg = msg;}public T getData() {return data;}public void setData(T data) {this.data = data;}
}

ResultVOUtil工具类将girl数据转化为VO

package cn.wg.util;import cn.wg.vo.ResultVO;public class ResultVOUtil {public static ResultVO convert(Integer code, String msg, Object object){ResultVO resultVO = new ResultVO();resultVO.setCode(code);resultVO.setMsg(msg);resultVO.setData(object);return resultVO;}
}

使用Tomcat启动项目

测试接口连接http://localhost:8080/ssm/girl/find/4
测试效果如下图：

第一次在IDEA上搭建ssm框架，配置配置比较复杂，记住配置文件结构，之间的关联关系，理解项目配置文件运行过程，就不容易错。