简介
MyBatis 是一款优秀的持久层框架，它支持定制化 SQL、存储过程以及高级映射。MyBatis 避免了几乎所有的 JDBC 代码和手动设置参数以及获取结果集。MyBatis 可以使用简单的 XML 或注解来配置和映射原生类型、接口和 Java 的 POJO（Plain Old Java Objects，普通老式 Java 对象）为数据库中的记录。
一、创建Maven工程并编辑pom.xml
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0http://maven.apache.org/xsd/maven-4.0.0.xsd"> <modelVersion>4.0.0modelVersion> <groupId>mabatis_v1.0groupId> <artifactId>mabatis_v1.0artifactId> <version>0.0.1-SNAPSHOTversion> <packaging>warpackaging> <build> <sourceDirectory>srcsourceDirectory> <plugins> <plugin> <artifactId>maven-compiler-pluginartifactId> <version>3.3version> <configuration> <source>1.8source> <target>1.8target> configuration> plugin> <plugin> <artifactId>maven-war-pluginartifactId> <version>2.6version> <configuration> <warSourceDirectory>WebContentwarSourceDirectory> <failOnMissingWebXml>falsefailOnMissingWebXml> configuration> plugin> plugins> build> <dependencies> <dependency> <groupId>org.mybatisgroupId> <artifactId>mybatisartifactId> <version>3.2.8version> dependency> <dependency> <groupId>junitgroupId> <artifactId>junitartifactId> <version>4.10version> dependency> dependencies> project>
二、创建java类
三、创建java对象与数据库之间的xml文件
NewsMapper.xml
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.hedong.dao.NewsMapper" >
<resultMap id="BaseResultMap" type="com.hedong.pojo.News" >
<id column="newsID" property="newsid" jdbcType="INTEGER" />
<result column="newsType" property="newstype" jdbcType="VARCHAR" />
<result column="newsTitle" property="newstitle" jdbcType="VARCHAR" />
<result column="newsWriter" property="newswriter" jdbcType="VARCHAR" />
<result column="newsTime" property="newstime" jdbcType="TIMESTAMP" />
resultMap>
<resultMap id="ResultMapWithBLOBs" type="com.hedong.pojo.News" extends="BaseResultMap" >
<result column="newsContent" property="newscontent" jdbcType="LONGVARCHAR" />
resultMap>
<sql id="Example_Where_Clause" >
<where >
<foreach collection="oredCriteria" item="criteria" separator="or" >
<if test="criteria.valid" >
<trim prefix="(" suffix=")" prefixOverrides="and" >
<foreach collection="criteria.criteria" item="criterion" >
<choose >
<when test="criterion.noValue" >
and ${criterion.condition}
when>
<when test="criterion.singleValue" >
and ${criterion.condition} #{criterion.value}
when>
<when test="criterion.betweenValue" >
and ${criterion.condition} #{criterion.value} and #{criterion.secondValue}
when>
<when test="criterion.listValue" >
and ${criterion.condition}
<foreach collection="criterion.value" item="listItem" open="(" close=")" separator="," >
#{listItem}
foreach>
when>
choose>
foreach>
trim>
if>
foreach>
where>
sql>
<sql id="Update_By_Example_Where_Clause" >
<where >
<foreach collection="example.oredCriteria" item="criteria" separator="or" >
<if test="criteria.valid" >
<trim prefix="(" suffix=")" prefixOverrides="and" >
<foreach collection="criteria.criteria" item="criterion" >
<choose >
<when test="criterion.noValue" >
and ${criterion.condition}
when>
<when test="criterion.singleValue" >
and ${criterion.condition} #{criterion.value}
when>
<when test="criterion.betweenValue" >
and ${criterion.condition} #{criterion.value} and #{criterion.secondValue}
when>
<when test="criterion.listValue" >
and ${criterion.condition}
<foreach collection="criterion.value" item="listItem" open="(" close=")" separator="," >
#{listItem}
foreach>
when>
choose>
foreach>
trim>
if>
foreach>
where>
sql>
<sql id="Base_Column_List" >
newsID, newsType, newsTitle, newsWriter, newsTime
sql>
<sql id="Blob_Column_List" >
newsContent
sql>
<select id="selectByExampleWithBLOBs" resultMap="ResultMapWithBLOBs" parameterType="com.hedong.pojo.NewsExample" >
select
<if test="distinct" >
distinct
if>
<include refid="Base_Column_List" />
,
<include refid="Blob_Column_List" />
from news_tb
<if test="_parameter != null" >
<include refid="Example_Where_Clause" />
if>
<if test="orderByClause != null" >
order by ${orderByClause}
if>
select>
<select id="selectByExample" resultMap="BaseResultMap" parameterType="com.hedong.pojo.NewsExample" >
select
<if test="distinct" >
distinct
if>
<include refid="Base_Column_List" />
from news_tb
<if test="_parameter != null" >
<include refid="Example_Where_Clause" />
if>
<if test="orderByClause != null" >
order by ${orderByClause}
if>
select>
<select id="selectByPrimaryKey" resultMap="ResultMapWithBLOBs" parameterType="java.lang.Integer" >
select
<include refid="Base_Column_List" />
,
<include refid="Blob_Column_List" />
from news_tb
where newsID = #{newsid,jdbcType=INTEGER}
select>
<delete id="deleteByPrimaryKey" parameterType="java.lang.Integer" >
delete from news_tb
where newsID = #{newsid,jdbcType=INTEGER}
delete>
<delete id="deleteByExample" parameterType="com.hedong.pojo.NewsExample" >
delete from news_tb
<if test="_parameter != null" >
<include refid="Example_Where_Clause" />
if>
delete>
<insert id="insert" parameterType="com.hedong.pojo.News" >
insert into news_tb (newsID, newsType, newsTitle,
newsWriter, newsTime, newsContent
)
values (#{newsid,jdbcType=INTEGER}, #{newstype,jdbcType=VARCHAR}, #{newstitle,jdbcType=VARCHAR},
#{newswriter,jdbcType=VARCHAR}, #{newstime,jdbcType=TIMESTAMP}, #{newscontent,jdbcType=LONGVARCHAR}
)
insert>
<insert id="insertSelective" parameterType="com.hedong.pojo.News" >
insert into news_tb
<trim prefix="(" suffix=")" suffixOverrides="," >
<if test="newsid != null" >
newsID,
if>
<if test="newstype != null" >
newsType,
if>
<if test="newstitle != null" >
newsTitle,
if>
<if test="newswriter != null" >
newsWriter,
if>
<if test="newstime != null" >
newsTime,
if>
<if test="newscontent != null" >
newsContent,
if>
trim>
<trim prefix="values (" suffix=")" suffixOverrides="," >
<if test="newsid != null" >
#{newsid,jdbcType=INTEGER},
if>
<if test="newstype != null" >
#{newstype,jdbcType=VARCHAR},
if>
<if test="newstitle != null" >
#{newstitle,jdbcType=VARCHAR},
if>
<if test="newswriter != null" >
#{newswriter,jdbcType=VARCHAR},
if>
<if test="newstime != null" >
#{newstime,jdbcType=TIMESTAMP},
if>
<if test="newscontent != null" >
#{newscontent,jdbcType=LONGVARCHAR},
if>
trim>
insert>
<select id="countByExample" parameterType="com.hedong.pojo.NewsExample" resultType="java.lang.Integer" >
select count(*) from news_tb
<if test="_parameter != null" >
<include refid="Example_Where_Clause" />
if>
select>
<update id="updateByExampleSelective" parameterType="map" >
update news_tb
<set >
<if test="record.newsid != null" >
newsID = #{record.newsid,jdbcType=INTEGER},
if>
<if test="record.newstype != null" >
newsType = #{record.newstype,jdbcType=VARCHAR},
if>
<if test="record.newstitle != null" >
newsTitle = #{record.newstitle,jdbcType=VARCHAR},
if>
<if test="record.newswriter != null" >
newsWriter = #{record.newswriter,jdbcType=VARCHAR},
if>
<if test="record.newstime != null" >
newsTime = #{record.newstime,jdbcType=TIMESTAMP},
if>
<if test="record.newscontent != null" >
newsContent = #{record.newscontent,jdbcType=LONGVARCHAR},
if>
set>
<if test="_parameter != null" >
<include refid="Update_By_Example_Where_Clause" />
if>
update>
<update id="updateByExampleWithBLOBs" parameterType="map" >
update news_tb
set newsID = #{record.newsid,jdbcType=INTEGER},
newsType = #{record.newstype,jdbcType=VARCHAR},
newsTitle = #{record.newstitle,jdbcType=VARCHAR},
newsWriter = #{record.newswriter,jdbcType=VARCHAR},
newsTime = #{record.newstime,jdbcType=TIMESTAMP},
newsContent = #{record.newscontent,jdbcType=LONGVARCHAR}
<if test="_parameter != null" >
<include refid="Update_By_Example_Where_Clause" />
if>
update>
<update id="updateByExample" parameterType="map" >
update news_tb
set newsID = #{record.newsid,jdbcType=INTEGER},
newsType = #{record.newstype,jdbcType=VARCHAR},
newsTitle = #{record.newstitle,jdbcType=VARCHAR},
newsWriter = #{record.newswriter,jdbcType=VARCHAR},
newsTime = #{record.newstime,jdbcType=TIMESTAMP}
<if test="_parameter != null" >
<include refid="Update_By_Example_Where_Clause" />
if>
update>
<update id="updateByPrimaryKeySelective" parameterType="com.hedong.pojo.News" >
update news_tb
<set >
<if test="newstype != null" >
newsType = #{newstype,jdbcType=VARCHAR},
if>
<if test="newstitle != null" >
newsTitle = #{newstitle,jdbcType=VARCHAR},
if>
<if test="newswriter != null" >
newsWriter = #{newswriter,jdbcType=VARCHAR},
if>
<if test="newstime != null" >
newsTime = #{newstime,jdbcType=TIMESTAMP},
if>
<if test="newscontent != null" >
newsContent = #{newscontent,jdbcType=LONGVARCHAR},
if>
set>
where newsID = #{newsid,jdbcType=INTEGER}
update>
<update id="updateByPrimaryKeyWithBLOBs" parameterType="com.hedong.pojo.News" >
update news_tb
set newsType = #{newstype,jdbcType=VARCHAR},
newsTitle = #{newstitle,jdbcType=VARCHAR},
newsWriter = #{newswriter,jdbcType=VARCHAR},
newsTime = #{newstime,jdbcType=TIMESTAMP},
newsContent = #{newscontent,jdbcType=LONGVARCHAR}
where newsID = #{newsid,jdbcType=INTEGER}
update>
<update id="updateByPrimaryKey" parameterType="com.hedong.pojo.News" >
update news_tb
set newsType = #{newstype,jdbcType=VARCHAR},
newsTitle = #{newstitle,jdbcType=VARCHAR},
newsWriter = #{newswriter,jdbcType=VARCHAR},
newsTime = #{newstime,jdbcType=TIMESTAMP}
where newsID = #{newsid,jdbcType=INTEGER}
update>
mapper>
四、创建confg.xml文件
五、创建SqlSessionFactory，获取session
