java框架之mybatis

public class MybatisTest {
    public static void main(String[] args) throws IOException {
        InputStream inputStream = Resources.getResourceAsStream("mybatis-config.xml");
        SqlSessionFactory sqlSessionFactory = new SqlSessionFactoryBuilder().build(inputStream);
        SqlSession sqlSession = sqlSessionFactory.openSession();
        User user = sqlSession.selectOne("MyMapper.selectUser",1);
        System.out.println(user);
    }
}

<build>
    <resources>
        <resource>
            <directory>src/main/java</directory>
            <includes>
                <include>**/*.properties</include>
                <include>**/*.xml</include>
            </includes>
            <filtering>false</filtering>
        </resource>
        <resource>
            <directory>src/main/resources</directory>
            <includes>
                <include>**/*.properties</include>
                <include>**/*.xml</include>
            </includes>
            <filtering>false</filtering>
        </resource>
    </resources>
</build>

<!--配置全局属性-->
<settings>
    <!-- 开启驼峰命名转换 ：{name_id}  -> {nameId}    -->
    <setting name="mapUnderscoreToCamelCase" value="true"/>
</settings>

<selectKey order="AFTER"keyProperty="id" resultType="String">select last_insert_id()</selectKey>

<selectKey keyColumn="id" keyProperty="id" order="BEFORE" resultType="int">
    select max(id)+1 as myNo from emp
</selectKey>

<!--序列实现自增主键-->
SQL >create sequence autoID increment by 1 start with 1 maxvalue 999999 cycle; 
SQL >insert into tablename values(autoID.nextval,...);

<resultMap id="myuser" type="com.stan.hello.User">
    <!--<id column="id" property="id"></id>-->
    <result column="user_name" property="userName"></result>
</resultMap>

<select id="queryUserById" resultMap="myuser" parameterType="java.lang.String">
  select * from tb_user where id = #{id}
</select>

<select id="queryUserList" resultType="com.stan.pojo.User">
    select * from tb_user WHERE 1=1
    <if test="name!=null and name.trim()!=''">
      and name like '%${name}%'
    </if>
</select>

<!--if 判断拼接 where 条件存在多余 and 的解决方法：加一个 1=1；使用where 或者 trim标签；-->

<select id="queryUserByNameOrAge" resultType="com.stan.pojo.User">
    select * from tb_user WHERE 1=1
    <choose>
        <when test="name!=null and name.trim()!=''">
            and name like '%${name}%'
        </when>
        <when test="age!=null">
            and age = #{age}
        </when>
        <otherwise>
            and name='allen'
        </otherwise>
    </choose>
</select>

List<User> queryUserByIds(@Param("ids") String[] ids);

<select id="queryUserByIds" resultType="com.stan.pojo.User">
    select * from tb_user where id in
    <foreach collection="ids" item="id" open="(" close=")" separator=",">
        #{id}
    </foreach>
</select>

<select id="queryUserByNameAndAge" resultType="com.stan.pojo.User">
    select * from tb_user
    <where>
        <if test="name!=null and name.trim()!=''">
            and name like '%${name}%'
        </if>
        <if test="age!=null">
            and age = #{age}
        </if>
    </where>
</select>

<update id="updateUser">
    update tb_user
    <set>
        <if test="userName != null and userName.trim() != ''">
            user_name=#{userName}
        </if>
        <if test="password != null and password.trim() != ''">
            password=#{password}
        </if>
    </set>
    where id = #{id}
</update>

update tb_user
<trim prefix="set" suffixoverride="," suffix=" where id = #{id} ">
    <if test="userName != null and userName.length()>0"> user_name=#{userName} , </if>
    <if test="password != null and password.length()>0"> password=#{password} ,  </if>
</trim>

<select id="getEmpsTestInnerParameter" resultType="com.hand.mybatis.bean.Employee">
  <bind name="bindeName" value="'%'+userName+'%'"/> 
  SELECT * FROM tb_user 
  <if test="userName!=null">
    where user_name like #{bindeName}
  </if>
</select>

<sql id="commonSql">id,user_name,password</sql>
<select id="queryUserById" resultMap="userResultMap">
    select <include refid="commonSql"></include> from tb_user where id = #{id}
</select>

<dependency>
    <groupId>org.mybatis.caches</groupId>
    <artifactId>mybatis-ehcache</artifactId>
    <version>1.1.0</version>
</dependency>
<dependency>
    <groupId>net.sf.ehcache</groupId>
    <artifactId>ehcache</artifactId>
    <version>2.10.5</version>
</dependency>

<?xml version="1.0" encoding="UTF-8"?>
<ehcache xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:noNamespaceSchemaLocation="http://ehcache.org/ehcache.xsd">
        <diskStore path="D:ehcache" />
        <defaultCache
                maxElementsInMemory="1000"
                maxElementsOnDisk="10000000"
                eternal="false"
                overflowToDisk="false"
                timeToIdleSeconds="120"
                timeToLiveSeconds="120"
                diskExpiryThreadIntervalSeconds="120"
                memoryStoreEvictionPolicy="LRU">
        </defaultCache>
</ehcache>

<cache type="org.mybatis.caches.ehcache.EhcacheCache" >
    <property name="timeToIdleSeconds" value="3600"/>
    <property name="timeToLiveSeconds" value="3600"/>
    <property name="maxEntriesLocalHeap" value="1000"/>
    <property name="maxEntriesLocalDisk" value="10000000"/>
    <property name="memoryStoreEvictionPolicy" value="LRU"/>
</cache>

<cache-ref namespace="com.stan.crud.UserDaoMapper"/>

diskStore标签：指定数据在磁盘中的存储位置。
defaultCache标签：当借助CacheManager.add("demoCache")创建Cache时，EhCache便会采用<defalutCache/>指定的的管理策略
以下属性是必须的：
maxElementsInMemory - 在内存中缓存的element的最大数目 
maxElementsOnDisk - 在磁盘上缓存的element的最大数目，若是0表示无穷大
eternal - 设定缓存的elements是否永远不过期。如果为true，则缓存的数据始终有效，如果为false那么还要根据timeToIdleSeconds，timeToLiveSeconds判断
overflowToDisk - 设定当内存缓存溢出的时候是否将过期的element缓存到磁盘上
以下属性是可选的：
timeToIdleSeconds - 当缓存在EhCache中的数据前后两次访问的时间超过timeToIdleSeconds的属性取值时，这些数据便会删除，默认值是0,也就是可闲置时间无穷大
timeToLiveSeconds - 缓存element的有效生命期，默认是0.,也就是element存活时间无穷大
diskSpoolBufferSizeMB 这个参数设置DiskStore(磁盘缓存)的缓存区大小.默认是30MB.每个Cache都应该有自己的一个缓冲区.
diskPersistent - 在VM重启的时候是否启用磁盘保存EhCache中的数据，默认是false。
diskExpiryThreadIntervalSeconds - 磁盘缓存的清理线程运行间隔，默认是120秒。每个120s，相应的线程会进行一次EhCache中数据的清理工作
memoryStoreEvictionPolicy - 当内存缓存达到最大，有新的element加入的时候， 移除缓存中element的策略。默认是LRU（最近最少使用），可选的有LFU（最不常使用）和FIFO（先进先出）

<resultMap id="orderUserRM" type="com.stan.pojo.OrderUser" autoMapping="true">
    <association property="user" javaType="com.stan.pojo.User" autoMapping="true">
        <id property="id" column="user_id"></id>
    </association>
</resultMap>
<select id="queryOrderUserByOrderNumber" resultMap="orderUserRM" parameterType="String">
  select * from tb_order o
  left join tb_user u on o.user_id = u.id
  where o.order_number = #{number}
</select>

<resultMap id="orderUserRM" type="com.stan.pojo.OrderUser" autoMapping="true">
    <association property="user" javaType="com.stan.pojo.User" autoMapping="true">
        <id property="id" column="user_id"></id>
    </association>
    <collection property="details" autoMapping="true" javaType="list" ofType="com.stan.pojo.OrderDetail" >
　　　　　<!--这里的 OrderDetail 是订单和商品关系的媒介-->
        <id property="id" column="detial_id"></id>
        <association property="item" javaType="com.stan.pojo.Item" autoMapping="true">
            <id property="id" column="item_id"></id>
        </association>
    </collection>
</resultMap>
<select id="queryOrderItemByOrderNumber" resultMap="orderUserRM2" parameterType="String">
  select *,d.id as detial_id from tb_order o
  left join tb_user u on o.user_id = u.id
  left join tb_orderdetail d on o.id = d.order_id
  left join tb_item i on i.id = d.item_id
  where o.order_number = #{number}
</select>

<!--延迟加载关联查询总开关，association和collection标签里的fetchType也是设置加载的模式的-->
<setting name="lazyLoadingEnabled" value="true"/>
<!--设置为true的话，只要get一个关联的属性，所有的关联查询都会发出-->
<setting name="aggressiveLazyLoading" value="false"/>

<resultMap id="rm2" type="com.stan.pojo.OrderUser" autoMapping="true">
        <association property="user" javaType="com.stan.pojo.User" autoMapping="true" select="queryUserById" column="user_id">
　　　　 <!--这里的select指定关联的查询的 id，这里的column是传过去的参数-->
　　　　 <!--多个参数的传递可以用map，就是这样的形式：｛key1=col1，key2=col2｝-->
　　　　 </association>
</resultMap>
<select id="queryOrderByNumber" resultMap="rm2">
    select * from tb_order where order_number = #{number}
</select>

<!--这个方法不单独使用的话可以不在 mapper 接口中书写方法定义-->
<select id="queryUserById" resultType="com.stan.pojo.User">
    select * from tb_user where id = #{number}
</select>

OrderUser queryOrderByNumber(@Param("number") String number);

@Test
public void queryOrderByNumber() throws IOException {
    OrderMapper mapper = sqlSession.getMapper(OrderMapper.class);
    OrderUser orderUser = mapper.queryOrderByNumber("201807010001");
    System.out.println("----------------------");
    System.out.println(orderUser.getOrderNumber());
    System.out.println("--------------------");
    System.out.println(orderUser.getUser());
}

<dependency>
    <groupId>cglib</groupId>
    <artifactId>cglib</artifactId>
    <version>3.1</version>
</dependency>

EmployeeExample example = new EmployeeExample();
Criteria criteria = example.createCriteria();
criteria.andLastNameLike("%e%");
criteria.andGenderEqualTo("1");

Criteria criteria2 = example.createCriteria();
criteria2.andEmailLike("%e%");
example.or(criteria2);

@Intercepts({@Signature(type= ParameterHandler.class,method = "setParameters",args = {PreparedStatement.class})})
public class MyIntercepter implements Interceptor {
    public Object intercept(Invocation invocation) throws Throwable {
        System.out.println("要拦截的方法："+invocation.getMethod());
        MetaObject metaObject = SystemMetaObject.forObject(invocation.getTarget());
        Object para = metaObject.getValue("parameterObject");
        System.out.println("原来的参数是："+para);
        metaObject.setValue("parameterObject","5");
        return invocation.proceed();
    }

    public Object plugin(Object o) {
        System.out.println("包装的对象："+o.toString());
        return Plugin.wrap(o,this);
    }

    public void setProperties(Properties properties) {
        System.out.println(properties.getProperty("test"));
    }
}​

<dependency>
 <groupId>com.github.pagehelper</groupId>
 <artifactId>pagehelper</artifactId>
 <version>4.1.4</version>
</dependency>

<plugins>
    <plugin interceptor="com.github.pagehelper.PageHelper">
        <property name="dialect" value="mysql"/>
        <property name="offsetAsPageNum" value="false"/>
        <property name="rowBoundsWithCount" value="false"/>
        <property name="pageSizeZero" value="true"/>
        <property name="reasonable" value="false"/>
        <property name="supportMethodsArguments" value="false"/>
        <property name="returnPageInfo" value="none"/>
    </plugin>
</plugins>

<select id="queryUserPage" resultType="com.stan.pojo.User">
  select * from tb_user
</select>

public List<User> queryUserPage();

@Test
public void queryPage() throws IOException {
    Page<User> page = PageHelper.startPage(2,4);
    List<User> users = mapper.queryUserPage();
    for (User user :
            users) {
        System.out.println(user);
    }
    System.out.println(page);
}