ssm整合——Mybatis配置（1）

mybatis搭建-基于注解

1. 环境准备

1.1 新建maven的webapp项目

1.2 新建必要的目录和文件

1.3 文件配置

• pom.xml
• junit默认创建是4.11，手动改成4.12

<dependency>
  <!-- 单元测试，这里将原先的4.11版本改为了4.12-->
  <groupId>junit</groupId>
  <artifactId>junit</artifactId>
  <version>4.12</version>
  <scope>test</scope>
</dependency>
<dependency>
  <!-- mysql驱动包用于建立数据库连接-->
  <groupId>mysql</groupId>
  <artifactId>mysql-connector-java</artifactId>
  <version>8.0.18</version>
</dependency>
<dependency>
  <!-- mybatisjar包-->
  <groupId>org.mybatis</groupId>
  <artifactId>mybatis</artifactId>
  <version>3.5.2</version>
</dependency>
<dependency>
  <!-- 用于日志记录-->
  <groupId>log4j</groupId>
  <artifactId>log4j</artifactId>
  <version>1.2.17</version>
</dependency>

• log4j.properties

# Set root category priority to INFO and its only appender to CONSOLE.
#log4j.rootCategory=INFO, CONSOLE            debug   info   warn error fatal
log4j.rootCategory=debug, CONSOLE, LOGFILE

# Set the enterprise logger category to FATAL and its only appender to CONSOLE.
log4j.logger.org.apache.axis.enterprise=FATAL, CONSOLE

# CONSOLE is set to be a ConsoleAppender using a PatternLayout.
log4j.appender.CONSOLE=org.apache.log4j.ConsoleAppender
log4j.appender.CONSOLE.layout=org.apache.log4j.PatternLayout
log4j.appender.CONSOLE.layout.ConversionPattern=%d{ISO8601} %-6r [%15.15t] %-5p %30.30c %x - %m\n

# LOGFILE is set to be a File appender using a PatternLayout.
log4j.appender.LOGFILE=org.apache.log4j.FileAppender
# 可修改log文件的位置
log4j.appender.LOGFILE.File=G:\\axis.log   
log4j.appender.LOGFILE.Append=true
log4j.appender.LOGFILE.layout=org.apache.log4j.PatternLayout
log4j.appender.LOGFILE.layout.ConversionPattern=%d{ISO8601} %-6r [%15.15t] %-5p %30.30c %x - %m\n

• SqlMapConifg.xml

<?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">
<!-- 以上是该文件的约束头部信息-->

<configuration>
    <!-- 配置 mybatis 的环境 -->
    <environments default="mysql">
        <!-- 配置 mysql 的环境 -->
        <environment id="mysql">
            <!-- 配置事务的类型 -->
            <transactionManager type="JDBC"></transactionManager>
            <!-- 配置连接数据库的信息：用的是数据源(连接池) -->
            <dataSource type="POOLED">
                <property name="driver" value="com.mysql.cj.jdbc.Driver"/>
                <property name="url" value="jdbc:mysql://localhost:3306/mybatistest?serverTimezone=Asia/Shanghai"/>
                <property name="username" value="root"/>
                <property name="password" value="123456"/>
            </dataSource>
        </environment>
    </environments>
    <!-- 告知 mybatis 映射配置的位置,，映射配置文件指的是每个dao的配置文件 -->
    <mappers>
        <!-- 使用xml文件配置sql语句时
        <mapper resource="com/ow/dao/IUserDao.xml"/>-->
        <!-- 使用注解配置sql语句时 -->
        <mapper class="com.ow.dao.IUserDao"></mapper>
    </mappers>
</configuration>

2. 编写程序

2.1 User.java

基于注解配置需要保持domain类的字段名称和数据库的字段名称相同

• 省略get，set方法，以及toString方法

public class User {
   
   
    private Integer id;
    private String name;
    private Float money;

2.2 IUserDao.java

public interface IUserDao {
   
   

    //插入用户，这里的id是自增键
    @Update("insert into account(name,money) values (#{name},#{money})")
    void saveUser(User user);

    //删除一个用户
    @Update("delete from account where id = #{uid}")
    void deleteUser(Integer uid);

    //更新用户
    @Update("update account set name=#{name},money=#{money} where id=#{id}")
    void updateUser(