SSM2021
Mybatis（ieda）
- 一款优秀的持久层框架
- 官网：Mybatis-3官网
- Maven仓库：
mavenRepositroy
- 数据库：
CREATE TABLE `user`(
`id` INT(20) NOT NULL PRIMARY KEY,
`name` VARCHAR(30) DEFAULT NULL,
`pwd` VARCHAR(30) DEFAULT NULL
)ENGINE=INNODB CHARSET=utf8;
INSERT INTO `user`(`id`,`name`,`pwd`) VALUES
(1,'lix','123456'),
(2,'admin','123456'),
(3,'root','123456')
- 导入依赖
<dependencies>
<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<version>4.12</version>
<scope>test</scope>
</dependency>
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<version> 5.1.47</version>
</dependency>
<dependency>
<groupId>com.mchange</groupId>
<artifactId>c3p0</artifactId>
<version>0.9.5.2</version>
</dependency>
<dependency>
<groupId>javax.servlet</groupId>
<artifactId>servlet-api</artifactId>
<version>2.5</version>
</dependency>
<dependency>
<groupId>javax.servlet.jsp</groupId>
<artifactId>jsp-api</artifactId>
<version>2.2</version>
</dependency>
<dependency>
<groupId>javax.servlet</groupId>
<artifactId>jstl</artifactId>
<version>1.2</version>
</dependency>
<dependency>
<groupId>org.mybatis</groupId>
<artifactId>mybatis</artifactId>
<version>3.5.4</version>
</dependency>
<dependency>
<groupId>org.mybatis</groupId>
<artifactId>mybatis-spring</artifactId>
<version>2.0.5</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-webmvc</artifactId>
<version>5.2.12.RELEASE</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-jdbc</artifactId>
<version>5.2.8.RELEASE</version>
</dependency>
</dependencies>
-
1、添加applicationContext表头
<?xml version="1.0" encoding="UTF-8"?> <beans xmlns="http://www.springframework.org/schema/beans" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.springframework.org/schema/beans https://www.springframework.org/schema/beans/spring-beans.xsd"> </beans>4.2、添加mybatis配置文件-----表头：
<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE configuration
PUBLIC "-//mybatis.org//DTD Config 3.0//EN"
"http://mybatis.org/dtd/mybatis-3-config.dtd">
<configuration>
</configuration>
4.3、添加database.properties文件
jdbc.driver=com.mysql.cj.jdbc.Driver
#如果使用的是MySQL8.0+ ，需要增加一个时区的配置 &serverTime=Asia/Shanghai
jdbc.url=jdbc:mysql://localhost:3306/ssmbuild?useSSL=true&useUnicode=true&characterEncoding=utf-8
jdbc.username=******
jdbc.password=******
4.4、添加mapper表头
<?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="">
</mapper>
4.5、编写dao层-----
- 接口
package com.lix.dao;
import com.lix.pojo.Books;
import org.apache.ibatis.annotations.Param;
import java.util.List;
public interface BookMapper {
int addBook(Books books);
int deleteBookById(@Param("bookId") int id);
int updateBook(Books books);
Books queryBookById(@Param("bookId") int id);
List<Books> queryAllBook();
}
-
实现
<?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.lix.dao.BookMapper"> <insert id="addBook" parameterType="Books"> insert into ssmbuild.books (bookName,bookCounts,detail) values (#{bookName},#{bookCounts},#{detail}); </insert> <delete id="deleteBookById" parameterType="int"> delete from ssmbuild.books where bookID = #{bookId} </delete> <update id="updateBook" parameterType="Books"> update ssmbuild.books set bookName=#{bookName},bookCounts=#{bookCounts},detail=#{detail} where bookID=#{bookID} </update> <select id="queryBookById" resultType="Books"> select * from ssmbuild.books where bookID = #{bookId} </select> <select id="queryAllBook" resultType="Books"> select * from ssmbuild.books </select> </mapper>4.6、编写service层------
- 接口
package com.lix.service; import com.lix.pojo.Books; import org.apache.ibatis.annotations.Param; import java.util.List; public interface BookService { int addBook(Books books); int deleteBookById(int id); int updateBook(Books books); Books queryBookById(int id); List<Books> queryAllBook(); }-
实现
package com.lix.service; import com.lix.dao.BookMapper; import com.lix.pojo.Books; import java.util.List; public class BookServiceImpl implements BookService { private BookMapper bookMapper; public void setBookMapper(BookMapper bookMapper) { this.bookMapper = bookMapper; } public int addBook(Books books) { return bookMapper.addBook(books); } public int deleteBookById(int id) { return bookMapper.deleteBookById(id); } public int updateBook(Books books) { return bookMapper.updateBook(books); } public Books queryBookById(int id) { return bookMapper.queryBookById(id); } public List<Books> queryAllBook() { return bookMapper.queryAllBook(); } }------mybatis层完结
------spring层开始-----
5.spring整合dao层
<?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"
xsi:schemaLocation="http://www.springframework.org/schema/beans
https://www.springframework.org/schema/beans/spring-beans.xsd
http://www.springframework.org/schema/context
https://www.springframework.org/schema/context/spring-context.xsd">
<!-- 关联数据库配置文件-->
<context:property-placeholder location="classpath:database.properties"/>
<!-- 连接池
dbcp:半自动化操作，不能自动连接
c3p0:自动化操作（自动化的加载配置文件，并且可以自动设置到对象中！）
druid:
hikari:
-->
<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}"/>
<!-- c3p0的私有属性-->
<property name="maxPoolSize" value="30"/>
<property name="minPoolSize" value="10"/>
<!-- 关闭连接后不自动commit-->
<property name="autoCommitOnClose" value="false"/>
<!-- 获取连接超时时间-->
<property name="checkoutTimeout" value="10000"/>
<!-- 当 获取连接失败 重试次数-->
<property name="acquireRetryAttempts" value="2"/>
</bean>
<!-- sqlSessionFactory-->
<bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">
<property name="dataSource" ref="dataSource"/>
<!-- 绑定mybatis配置文件-->
<property name="configLocation" value="classpath:mybatis-config.xml"/>
</bean>
<!-- 配置dao接口扫描包，动态实现了Dao接口可以注入到Spring容器中-->
<bean class="org.mybatis.spring.mapper.MapperScannerConfigurer">
<!-- 注入sqlSessionFactory-->
<property name="sqlSessionFactoryBeanName" value="sqlSessionFactory"/>
<!-- 要扫描的dao包-->
<property name="basePackage" value="com.lix.dao"/>
</bean>
</beans>
6.spring整合service层
<?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"
xsi:schemaLocation="http://www.springframework.org/schema/beans
https://www.springframework.org/schema/beans/spring-beans.xsd
http://www.springframework.org/schema/context
https://www.springframework.org/schema/context/spring-context.xsd">
<!-- 扫描service下的包-->
<context:component-scan base-package="com.lix.service"/>
<!-- 将我们所有的业务类，注入到spring，可以通过配置，或者注解实现-->
<bean id="BookServiceImpl" class="com.lix.service.BookServiceImpl">
<property name="bookMapper" ref="bookMapper"/>
</bean>
<!-- 声明式事务-->
<bean id="transactionManager" class="org.springframework.jdbc.datasource.DataSourceTransactionManager">
<!-- 注入数据源-->
<property name="dataSource" ref="dataSource"/>
</bean>
<!-- aop事务支持-->
<tx:advice id="txAdvice" transaction-manager="transactionManager">
<tx:attributes>
<tx:method name="*" propagation="REQUIRED"/>
</tx:attributes>
</tx:advice>
<aop:config>
<aop:pointcut id="txPointCut" expression="execution(* com.lix.dao.*.*(..))"/>
<aop:advisor advice-ref="txAdvice" pointcut-ref="txPointCut"/>
</aop:config>
</beans>
7.spring整合controller层
<?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
https://www.springframework.org/schema/beans/spring-beans.xsd
http://www.springframework.org/schema/context
https://www.springframework.org/schema/context/spring-context.xsd
http://www.springframework.org/schema/mvc
http://www.springframework.org/schema/mvc/spring-mvc.xsd">
<!-- 注解驱动 -->
<mvc:annotation-driven/>
<!-- 静态资源过滤 -->
<mvc:default-servlet-handler/>
<!-- 扫描包 -->
<context:component-scan base-package="com.lix.controller"/>
<!-- 视图解析器-->
<bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">
<property name="prefix" value="/WEB-INF/jsp/"/>
<property name="suffix" value=".jsp/"/>
</bean>
</beans>
------项目框架搭建完成-----
-
报错：
Could not find resource org/mybatis/example/mybatis-config.xml
-
解决：纯配置文件路径错误，检查路径即可
-
报错：
org.apache.ibatis.builder.BuilderException: Error parsing SQL Mapper Configuration. Cause: java.io.IOException: Could not find resource-
解决：在pom.xml中加入以下配置
<build> <resources> <resource> <directory>src/main/resources</directory> <includes> <include>**/*.properties</include> <include>**/*.xml</include> </includes> <filtering>true</filtering> </resource> <resource> <directory>src/main/java</directory> <includes> <include>**/*.properties</include> <include>**/*.xml</include> </includes> <filtering>true</filtering> </resource> </resources> </build>- log4j配置文件
-
#将等级为DEBUG的日志信息输出到console和file这两个目的地，console和file的定义在下面的代码
log4j.rootLogger=DEBUG,console,file
#控制台输出的相关设置
log4j.appender.console = org.apache.log4j.ConsoleAppender
log4j.appender.console.Target = System.out
log4j.appender.console.Threshold = Debug
log4j.appender.console.layout = org.apache.log4j.PatternLayout
log4j.appender.console.layout.ConversionPattern = [%c]-%m%n
#文件输出的相关设置
log4j.appender.file = org.apache.log4j.RollingFileAppender
log4j.appender.file.File = ./log/lix.log
log4j.appender.file.MaxFileSize = 10mb
log4j.appender.file.Threshold = DEBUG
log4j.appender.file.layout = org.apache.log4j.PatternLayout
log4j.appender.file.layout.ConversionPattern = [%p][%d{yy-mm-dd}][%c]%m%n
#日志输出级别
log4j.logger.org.mybatis = DEBUG
log4j.logger.java.sql = DEBUG
log4j.logger.java.sql.Statement = DEBUG
log4j.logger.java.sql.ResultSet = DEBUG
log4j.logger.java.sql.PreparedStatement = DEBUG
二.注解CRUD
package com.lix.dao;
import com.lix.pojo.User;
import org.apache.ibatis.annotations.*;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
/**
* program mybatis-01
* @author lix
*/
public interface UserMapper {
/**
* getUsers
* @return
*/
@Select("select * from user")
List<User> getUsers();
/**
*
* getUserById
* @param id
* @param name
* @return
* 方法存在多个参数，
*/
@Select("select * from user where id=#{id}")
User getUserById(@Param("id") int id, @Param("name") String name);
/**
* addUser
* @param map
* @return
*/
@Insert("insert into user(id,name,pwd) values(#{id},#{name},#{pwd})")
int addUser(Map<String,Object> map);
/**
* updateUser
* @param map
* @return
*/
@Update("update user set name = #{name},pwd=#{pwd} where id = #{id}")
int updateUser(Map<String,Object> map);
/**
* deleteUse
* @param id
* @return
*/
@Delete("delete from user where id = #{id}")
int deleteUse(@Param("id") int id);
}
【注意：我们必须要把核心配置类（UserMapper.java）绑定到核心配置文件中（mybatis-config.xml）】
-
关于@Param()注解
- 基本类型的参数或者String类型，需要加
- 引用类型不需要加
- 如果只有一个基本类型的话，可以忽略，建议加
- 我们在SQL中引用的就是我们这里的的@Param()中设定的属性名
-
{} 可以很大程度的防止sql注入 ${}
-
Lombok
-
Project Lombok is a java library that automatically plugs into your editor and build tools, spicing up your java.
Never write another getter or equals method again, with one annotation your class has a fully featured builder, Automate your logging variables, and much more.-
Project Lombok是一个java库，它可以自动插入到你的编辑器和构建工具中，为您的java注入新的活力。
不要再编写其他getter或equals方法，有了一个注释，类就有了功能齐全的构建器、自动化日志变量等等。
-
-
package com.lix.dao; import lombok.AllArgsConstructor; import lombok.Data; import lombok.NoArgsConstructor; /** * program mybatis-02 * @author lix * description 加在类上所有属性都加，加在属性上，只有属性加 */ @Data @AllArgsConstructor @NoArgsConstructor public class User { private int id; private String name; private String pwd; }
-
4.1、按照查询嵌套处理
<select id="getStudent" resultMap="StudentTeacher">
select * from student
</select>
<resultMap id="StudentTeacher" type="Student">
<result column="id" property="id"/>
<result column="name" property="name"/>
<!--复杂属性单独处理
对象：association
集合：collection
-->
<association property="teacher" column="tid" javaType="Teacher" select="getTeacher"/>
<collection property=""/>
</resultMap>
<select id="getTeacher" resultType="Teacher">
select * from teacher where id = #{tid};
</select>
三.动态SQL
<select id="iii" resultType="sss">
select * from mybatis.user
<where>
<if test="title != null">
title =1
</if>
</where>
<set></set>
</select>
本文来自博客园，作者：六爻呈乾，转载请注明原文链接：https://www.cnblogs.com/ilycq/p/15149205.html
