1. 介绍
Ibatis是开源的持久层框架。它的核心是SqlMap,将实体Bean跟关系数据库进行映射,将业务代码和SQL语句的书写进行分开,方便管理。Ibatis是“半自动”的ORM持久层框架。这里的“半自动化”,是相对Hibernate等提供了全面的数据库封装机制的“全自动化”ORM 实现而言,“全自动”ORM 实现了 POJO 和数据库表之间的映射,以及 SQL 的自动生成和执行。而iBATIS 的着力点,则在于POJO 与 SQL之间的映射关系。也就是说,iBATIS并不会为程序员在运行期自动生成 SQL 执行。具体的 SQL 需要程序员编写,然后通过映射配置文件,将SQL所需的参数,以及返回的结果字段映射到指定 POJO。
2. 前提
1) 安装了MySql数据库;
2) 将以下Jar包加入工程的classpath:commons-logging-1.0.4.jar、ibatis-2.3.0.677.jar、mysql-connector-java-5.0.3-bin.jar。
3. 实例
3.1 在MySql数据库中创建数据库
- #############################################################################################
- CREATE DATABASE MYDB;
- use MYDB;
- Drop TABLE IF EXISTS `MYDB`.`student`;
- Create TABLE `MYDB`.`student` (
- `name` varchar(40) NOT NULL,
- `psw` varchar(10) NOT NULL,
- `enabled` boolean
- );
- insert into student values("lanp","lanpiao",true);
- insert into student values("ph","ph",true);
- insert into student values("wxh","wxh",true);
3.2 书写实体Bean:Student.java
- package com.lanp.beans;
- /**
- * Student Bean
- * @author LanP
- * @since 2011-11-27 15:36
- * @version V1.0
- */
- public class Student {
- private String name;
- private String psw;
- private Boolean enabled;
- public String getName() {
- return name;
- }
- public void setName(String name) {
- this.name = name;
- }
- public String getPsw() {
- return psw;
- }
- public void setPsw(String psw) {
- this.psw = psw;
- }
- public Boolean getEnabled() {
- return enabled;
- }
- public void setEnabled(Boolean enabled) {
- this.enabled = enabled;
- }
- }
3.3 配置数据库的属性文件:mysql.properties
- mysql.driver = com.mysql.jdbc.Driver
- mysql.url = jdbc:mysql://localhost:3306/MYDB
- mysql.username = root
- mysql.password = 157891
3.4 SqlMap配置文件:sqlMapConfig.xml
- <?xml version="1.0" encoding="UTF-8"?>
- <!DOCTYPE sqlMapConfig
- PUBLIC "-//ibatis.apache.org//DTD SQL Map Config 2.0//EN"
- "http://ibatis.apache.org/dtd/sql-map-config-2.dtd">
- <sqlMapConfig>
- <!-- Properties属性配置文件,加载数据库连接信息 -->
- <properties resource="mysql.properties"/>
- <settings
- cacheModelsEnabled="true"
- enhancementEnabled="true"
- lazyLoadingEnabled="true"
- errorTracingEnabled="true"
- maxRequests="32"
- maxSessions="10"
- maxTransactions="5"
- useStatementNamespaces="false"
- />
- <!-- 配置Ibatis事务管理,使用JDBC事务类型,数据源使用Simple类型 -->
- <transactionManager type="JDBC">
- <dataSource type="SIMPLE">
- <property name="JDBC.Driver" value="${mysql.driver}"/>
- <property name="JDBC.ConnectionURL" value="${mysql.url}"/>
- <property name="JDBC.Username" value="${mysql.username}"/>
- <property name="JDBC.Password" value="${mysql.password}"/>
- </dataSource>
- </transactionManager>
- <!-- 配置Ibatis要使用的SqlMap文件信息 -->
- <sqlMap resource="com/lanp/beans/student.xml"/>
- </sqlMapConfig>
3.5 student实体Bean的映射配置:student.xml
- <?xml version="1.0" encoding="UTF-8"?>
- <!DOCTYPE sqlMap
- PUBLIC "-//ibatis.apache.org//DTD SQL Map 2.0//EN"
- "http://ibatis.apache.org/dtd/sql-map-2.dtd">
- <sqlMap>
- <!-- 为Person类设置一个别名 -->
- <typeAlias alias="student" type="com.lanp.beans.Student"/>
- <!-- 配置表和实体Bean之间的映射关系 -->
- <resultMap id="studentMap" class="com.lanp.beans.Student">
- <result property="name" column="name"/>
- <result property="psw" column="psw"/>
- <result property="enabled" column="enabled"/>
- </resultMap>
- <insert id="insertStudent" parameterClass="student">
- <![CDATA[
- insert into student values(#name#,#psw#,#enabled#);
- ]]>
- </insert>
- <!-- 查看特定用户 -->
- <select id="queryStudentById" parameterClass="string" resultMap="studentMap">
- <![CDATA[
- SELECT * FROM STUDENT WHERE NAME=#name#
- ]]>
- </select>
- <!-- 查看所有的用户 -->
- <select id="queryAllStudents" resultMap="studentMap">
- <![CDATA[
- SELECT * FROM STUDENT
- ]]>
- </select>
- </sqlMap>
3.6 测试类:TestStudent.java
- package com.lanp.beans;
- import java.io.Reader;
- import java.util.List;
- import com.ibatis.common.resources.Resources;
- import com.ibatis.sqlmap.client.SqlMapClient;
- import com.ibatis.sqlmap.client.SqlMapClientBuilder;
- /**
- * 测试Ibatis
- * @author LanP
- * @since 2011-11-27 15:36
- * @version V1.0
- */
- public class TestStudent {
- public static void main(String[] args) {
- String resource = "sqlMapConfig.xml";
- try {
- //读取配置文件
- Reader reader = Resources.getResourceAsReader(resource);
- //得到SqlMapClient
- SqlMapClient sqlMap = SqlMapClientBuilder.buildSqlMapClient(reader);
- //新增学生信息
- insertStudent(sqlMap);
- //查看全部的学生
- queryAllStudents(sqlMap);
- //查看特定的学生
- queryStudentByName(sqlMap);
- } catch(Exception e){}
- }
- /**
- * 根据学生的名字查询特定的学生信息
- * @param sqlMap
- */
- private static void queryStudentByName(SqlMapClient sqlMap) {
- try {
- System.out.println("--------------查询特定的学生信息-------------------------");
- Student stu = (Student)sqlMap.queryForObject("queryStudentById", "lanp");
- if(null != stu) {
- System.out.println("== 学生名字: " + stu.getName() + " ,学生密码: " + stu.getPsw() + " ==");
- }
- } catch(Exception e){}
- }
- /**
- * 显示所有学生的信息
- * @param sqlMap
- */
- @SuppressWarnings("unchecked")
- private static void queryAllStudents(SqlMapClient sqlMap) {
- try {
- System.out.println("--------------查询所有的学生信息-------------------------");
- List<Student> students = sqlMap.queryForList("queryAllStudents");
- if(null != students && students.size()>0) {
- for(int i=0; i<students.size(); i++) {
- Student student = students.get(i);
- System.out.println("== 学生名字: " + student.getName() + " ,学生密码: " + student.getPsw() +" ==");
- }
- }
- } catch(Exception e){}
- }
- /**
- * 新增学生信息
- * @param sqlMap
- */
- private static void insertStudent(SqlMapClient sqlMap) {
- try {
- System.out.println("--------------新增学生信息-------------------------");
- Student student = new Student();
- student.setName("xinh");
- student.setPsw("123");
- student.setEnabled(true);
- //开始Ibatis事务
- sqlMap.startTransaction();
- sqlMap.insert("insertStudent", student);
- //结束IBatis事务
- sqlMap.commitTransaction();
- } catch(Exception e){}
- }
- }