??? 用了很久hibernate ，突然想换个别的orm 工具，当然在orm领域中，hibernate是老大。看了一下ibatis，发现如果对于crud操作不是很多的系统来说，是个不错的选择，尤其是适合那些对sql和性能热衷的开发者。综合来说ibatis不能算orm工具，只能算个半成品。不过比起直接用jdbc写，那还是方便多了。主要的好处是分离了sql和代码，如果你想追求性能，那么sql是你很好的利器，当然ibatis的缓存也不错。比起hibernate，ibatis就简单多了，估计也就3天能够基本掌握了，这大大减少了学习成本。
??? 说了那么多废话，下面开始正题，通过一个简单的实例开始ibatis之旅，文章大部分参考网上的ibatis 开发指南一文。
??? 主要的jar：ibatis 2.3.0,spring 2.0.1,log4j 1.2.9,commons-logging 1.0.4,hsqldb 1.8.0
???
ibatis实例配置：?
<sqlMapConfig>
<!-- 事务采用spring 管理 -->
? <!--
? <transactionManager type="JDBC" commitRequired="false">
??? <dataSource type="SIMPLE">
????? <property name="JDBC.Driver" value="org.hsqldb.jdbcDriver"/>
????? <property name="JDBC.ConnectionURL" value="jdbc:hsqldb:hsql://localhost/xdb"/>
????? <property name="JDBC.Username" value="sa"/>
????? <property name="JDBC.Password" value=""/>
??? </dataSource>
? </transactionManager>
-->
? <sqlMap resource="org/esoft/bo/xml/Account.xml"/>
</sqlMapConfig>?? ?
创建POJO对象：?
package com.esoft.bo;
public class Account {
??? private String emailAddress;
??? private String firstName;
??? private int id;
??? private String lastName;
??? public String getEmailAddress() {
??????? return emailAddress;
??? }
??? public String getFirstName() {
??????? return firstName;
??? }
??? public int getId() {
??????? return id;
??? }
??? public String getLastName() {
??????? return lastName;
??? }
??? public void setEmailAddress(String emailAddress) {
??????? this.emailAddress = emailAddress;
??? }
??? public void setFirstName(String firstName) {
??????? this.firstName = firstName;
??? }
??? public void setId(int id) {
??????? this.id = id;
??? }
??? public void setLastName(String lastName) {
??????? this.lastName = lastName;
??? }
}?? ?
映射文件，感觉比较的麻烦。以后有机会的话一定自动生成此文件，尤其现在jpa当道。
?
<?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 namespace="Account">
?? ?
?? ?<!-- Use type aliases to avoid typing the full classname every time. -->
?? ?<typeAlias alias="Account" type="com.esoft.bo.Account"/>
?? ?
?? ?<!-- Result maps describe the mapping between the columns returned
?? ?from a query, and the class properties.? A result map isn't
?? ?necessary if the columns (or aliases) match to the properties
?? ?exactly. -->
?? ?<resultMap id="AccountResult" class="Account">
?? ??? ?<result property="id" column="ACC_ID"/>
?? ??? ?<result property="firstName" column="ACC_FIRST_NAME"/>
?? ??? ?<result property="lastName" column="ACC_LAST_NAME"/>
?? ??? ?<result property="emailAddress" column="ACC_EMAIL"/>
?? ?</resultMap>
?? ?
?? ?<!-- Select with no parameters using the result map for Account class. -->
?? ?<select id="selectAllAccounts" resultMap="AccountResult">
?? ??? ?select * from ACCOUNT
?? ??? ?</select>
?? ?
?? ?<select id="selectByName" resultMap="AccountResult" parameterClass="String">
?? ??? ?select * from Account where ACC_FIRST_NAME like #name#
?? ?</select>
?? ?
?? ?<!-- A simpler select example without the result map.? Note the
?? ?aliases to match the properties of the target result class. -->
?? ?<select id="selectAccountById" parameterClass="int" resultClass="Account">
?? ??? ?select ACC_ID as id, ACC_FIRST_NAME as firstName, ACC_LAST_NAME as lastName,
?? ??? ?ACC_EMAIL as emailAddress from ACCOUNT where ACC_ID = #id# </select>
?? ?
?? ?<!-- Insert example, using the Account parameter class -->
?? ?<insert id="insertAccount" parameterClass="Account"> insert into ACCOUNT ( ACC_ID,
?? ??? ?ACC_FIRST_NAME, ACC_LAST_NAME, ACC_EMAIL) values ( #id#, #firstName#,
?? ??? ?#lastName#, #emailAddress# ) </insert>
?? ?
?? ?<!-- Update example, using the Account parameter class -->
?? ?<update id="updateAccount" parameterClass="Account"> update ACCOUNT set
?? ??? ?ACC_FIRST_NAME = #firstName#, ACC_LAST_NAME = #lastName#, ACC_EMAIL =
?? ??? ?#emailAddress# where ACC_ID = #id# </update>
?? ?
?? ?<!-- Delete example, using an integer as the parameter class -->
?? ?<delete id="deleteAccountById" parameterClass="int"> delete from ACCOUNT where
?? ??? ?ACC_ID = #id# </delete>
?? ?
?? ?<delete id="clearAccount"> delete from ACCOUNT </delete>
?? ?
</sqlMap>?? ?
spring 配置：?
...
<bean id="dataSource"
?? ??? ?class="org.springframework.jdbc.datasource.DriverManagerDataSource">
?? ??? ?<property name="driverClassName">
?? ??? ??? ?<value>${jdbc.driverClassName}</value>
?? ??? ?</property>
?? ??? ?<property name="url">
?? ??? ??? ?<value>${jdbc.url}</value>
?? ??? ?</property>
?? ??? ?<property name="username">
?? ??? ??? ?<value>${jdbc.username}</value>
?? ??? ?</property>
?? ??? ?<property name="password">
?? ??? ??? ?<value>${jdbc.password}</value>
?? ??? ?</property>
?? ?</bean>
???????? <bean id="transactionManager"
?? ??? ?class="org.springframework.jdbc.datasource.DataSourceTransactionManager">
?? ??? ?<property name="dataSource" ref="dataSource"/>
?? ? </bean>
?? ?
?????? <bean id="sqlMapClient"
?? ??? ?class="org.springframework.orm.ibatis.SqlMapClientFactoryBean">
?? ??? ?<property name="dataSource" ref="dataSource"/>
?? ??? ?<property name="configLocation">
?? ??? ??? ?<value>SqlMapConfig.xml</value>
?? ??? ?</property>
????? </bean>
????? <bean id="accountDao" class="org.esoft.dao.AccountDaoImpl">
???????????? <property name="sqlMapClient" ref="sqlMapClient"/>
????? </bean>?? ?? ?
?? ?
主要的代码：public class AccountDaoImpl
??????? extends SqlMapClientDaoSupport {
??? public PK save(Account obj) {
??????? return (PK) getSqlMapClientTemplate().insert("insertAccount", obj);
??? }
??? public void update(Accountobj) {
??????? getSqlMapClientTemplate().update("updateAccount", obj);
??? }
???? public void delete(Account obj) {
??????? getSqlMapClientTemplate().delete(
??????????????? "deleteAccountById",
??????????????? obj.getPk());
??? }
??? public Account get(PK primaryKey) {
??????? return (Account) getSqlMapClientTemplate().queryForObject(
??????????????? "selectAccountById",
??????????????? primaryKey);
??? }
}
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