SSM框架整合步骤

Spring Boot整合SSM三大框架（spring+springmvc+mybatis）的步骤。

1. 建立数据库表格

2. 建立实体 验证@Validated可以在属性上进行非空什么的
3. 建立接口：注意唯一和MyBatis不同的是，这个接口上需要加@Mapper注解
可以将@Mapper注解理解为@Component注解

4. 为每一个接口建立对应的映射文件

<?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">
<mapper namespace="接口路径">
<cache/>
<resultMap id="userResultMap" type="实体路径">
<id column="u_id" property="uId"/>
<result column="email" property="email"/>
<result column="password" property="password"/>
<result column="login_count" property="loginCount"/>
<result column="last_login_time" property="lastLoginTime" javaType="java.time.LocalDateTime" jdbcType="TIMESTAMP"/>
</resultMap>

<insert id="insert" parameterType="com.google.springmvc.domain.User" useGeneratedKeys="true" keyProperty="uId">
insert into users(email, password, login_count, last_login_time)
values(#{email}, #{password}, #{loginCount}, #{lastLoginTime})
</insert>

<update id="update" parameterType="com.google.springmvc.domain.User">
update users
<trim prefix="set" suffixOverrides="," >
<if test="email != null">email=#{email},</if>
<if test="password != null">password=#{password},</if>
<if test="loginCount != null">login_count=#{loginCount},</if>
<if test="lastLoginTime != null">last_login_time=#{lastLoginTime}</if>
</trim>
where u_id=#{uId}
</update>
</mapper>

5. 在application.properties中进行SSM的基本配置

spring.datasource.url=jdbc:mysql://localhost:3306/数据库名?characterEncoding=utf-8&serverTimezone=UTC
spring.datasource.driver-class-name=com.mysql.cj.jdbc.Driver
spring.datasource.username=用户名
spring.datasource.password=密码
mybatis.mapperLocations=classpath*:**/mappers/*.xml

6. 测试

@SpringBootTest
class SpringmvcApplicationTests {

@Autowired
private UserMapper userMapper;

@Test
void contextLoads() {
System.out.println(userMapper.selectByEmailAndPassword("tom@google.com", "123456"));
}

}

（转换类型）
@Component
public class DateFormatter implements Formatter<LocalDate> {
@Override
public LocalDate parse(String s, Locale locale) throws ParseException {
DateTimeFormatter dateTimeFormatter = DateTimeFormatter.ofPattern("yyyy-MM-dd");
return LocalDate.parse(s, dateTimeFormatter);
}

@Override
public String print(LocalDate date, Locale locale) {
return date.toString();
}
}

7. 书写service层
7.1 在service层中使用@Autowired注入需要Mapper
7.2 在service层的每个实现类上加入@Service注解
7.3 在service层的每个实现类上加入@Transactional注解

8. 测试一下service层代码（也可以不测试）
9. 写controller层：在控制器层注入service层即可。例如：

@Controller
public class StudentsController {
    @Autowired
    private StudentsService studentsService;

    @RequestMapping("/toSave")
    public String toSave() {
        return "saveStudent";
    }
    @RequestMapping("/save")
    public String save(Students students){
        studentsService.save(students);
        return "redirect:query";
    }

10. 写网页或者json进行测试