Mybatis基於註解的運用

依賴：
dependencies>
<!--mybatis依賴-->
<dependency>

<groupId>org.mybatis</groupId>
<artifactId>mybatis</artifactId>
<version>3.4.5</version>

</dependency>
<!--數據庫驅動包-->
<dependency>

<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<version>5.1.30</version>

</dependency>
<!--log4j日誌包（查看控制檯中mybatis生成的sql語句）-->
<dependency>

<groupId>log4j</groupId>
<artifactId>log4j</artifactId>
<version>1.2.17</version>

</dependency>
<dependency>

<groupId>org.mybatis</groupId>
<artifactId>mybatis</artifactId>
<version>3.4.5</version>

</dependency>
<dependency>

<groupId>junit</groupId>
<artifactId>junit</artifactId>
<version>4.0</version>

</dependency>
</dependencies>
實體類：
public class User { private int id;

private String username;
private Date birthday;
private String sex;
private String address;//省略getter/setter

}
config.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">

<configuration>

<properties resource="jdbc.properties"></properties>
<settings>
    <setting name="lazyLoadingEnabled" value="true"/>
</settings>

<typeAliases>
        <package name="test.mylo.entity"></package>

</typeAliases>
<!--environments配置數據庫環境（事務、鏈接池、鏈接參數）-->
<!--default 表示默認使用哪一個環境-->
<environments default="mysql">
    <environment id="mysql">
        <!--指定事務管理器-->
        <transactionManager type="JDBC"></transactionManager>
        <!--指定數據源（鏈接池）-->
        <dataSource type="POOLED">
            <property name="driver" value="${driver}"></property>
            <property name="url" value="${url}"></property>
            <property name="username" value="${username}"></property>
            <property name="password" value="${password}"></property>
        </dataSource>
    </environment>
</environments>

<mappers>

  <package name="test.mylo.mapper"></package>
</mappers>

</configuration>
UserMapper
package test.mylo.mapper;
import org.apache.ibatis.annotations.Insert;
import org.apache.ibatis.annotations.Options;
import org.apache.ibatis.annotations.Select;
import org.apache.ibatis.annotations.UpdateProvider;
import test.mylo.entity.User;
public interface UserMapper {

@Select("select  * from user where id = #{id}")
User findOne(Integer id);

@Insert("insert into user(username,birthday,sex,address) values(" +
        "#{username},#{birthday},#{sex},#{address})")
@Options(useGeneratedKeys = true,keyColumn = "id",keyProperty = "id")
void addUser(User user);

@UpdateProvider(method = "testUpdate" ,type = TestSQL.class)
User updateUser(User u);

}
TestSQL
package test.mylo.mapper;import test.mylo.entity.User;

import org.apache.ibatis.jdbc.SQL;
/**

• @program: workSet
• @description: 測試動態sql
• @author: Mylo
• @create: 2018-08-11 14:40

**/
public class TestSQL {

public String testUpdate(final User user){
    return new SQL(){{
        UPDATE("user");
                if (user.getUsername() != null){
                    SET(" username = #{username}");
                }
                if(user.getBirthday() != null){
                    SET("birthday =#{birthday}");
                }

                if(user.getAddress() != null){
                    SET("address = #{address}");
                }
            WHERE("id = #{id}");
    }
    }.toString();
}

}
Test
@Testpublic void testUpdateUser(){

SqlSession sqlSession = build.openSession();
UserMapper mapper = sqlSession.getMapper(UserMapper.class);
User user = new User();
user.setId(50);
user.setUsername("test33");
user.setSex("男");
user.setBirthday(new Date());
user.setAddress("test333");

mapper.updateUser(user);
sqlSession.commit();

}