ibatis实践

1.iBatis的总配置文件是sqlMapConfig.xml,其代码如下：

<?xml version="1.0" encoding="UTF-8" ?>

<!DOCTYPE sqlMapConfig     

PUBLIC"-//ibatis.apache.org//DTDSQLMapConfig2.0//EN"

    "http://ibatis.apache.org/dtd/sql-map-config-2.dtd">

<sqlMapConfig>

<!-- 加载属性文件-->

<propertiesresource="com/ibatis/sqlMap.properties"/>

<settings

cacheModelsEnabled="true"

enhancementEnabled="true"

lazyLoadingEnabled="true"

maxRequests="128"

maxSessions="10"

maxTransactions="5"

useStatementNamespaces="true"

defaultStatementTimeout="15"

statementCachingEnabled="true"

classInfoCacheEnabled="true"

/>

<transactionManagertype="JDBC">

<dataSourcetype="SIMPLE">

<propertyname="JDBC.Driver"value="${driver}"/>

<propertyname="JDBC.ConnectionURL"value="${url}"/>

<propertyname="JDBC.Username"value="${username}"/>

<propertyname="JDBC.Password"value="${password}"/>

</dataSource>

</transactionManager>

<!-- 加载sqlmap -->

<sqlMapresource="com/ibatis/Student.xml"/>

</sqlMapConfig>

2.属性文件sqlMap.properties是配置数据库的文件，其代码如下：

driver=oracle.jdbc.driver.OracleDriver

url=jdbc:oracle:thin:@127.0.0.1:1521:orcl

username=crws

password=crws

3.sqlMap文件Student.xml是具体的sql语句，其代码如下：

<?xml version="1.0" encoding="UTF-8" ?>

<!DOCTYPEsqlMap

PUBLIC"-//ibatis.apache.org//DTDSQLMap2.0//EN"

"http://ibatis.apache.org/dtd/sql-map-2.dtd">

<sqlMapnamespace="Student">

<typeAliasalias="Student"type="com.ibatis.Student"/>

<!--

<resultMapclass=""id="">

<resultproperty=""column=""/>

</resultMap>

-->

<!--查询所有记录-->

<selectid="selectAllStudent"resultclass="Student">

<!--

id代表下面的sql语句；resultClass的值Student代表com.ibatis.Student

-->

select*fromSTUDENT

</select>

<!--查询指定id的记录-->

<selectid="selectStudentById"parameterclass="int"resultclass="Student">

<!--

parameterClass代表要输入值的类型

-->

select*fromSTUDENTwheresid=#sid#

</select>

<!--插入一条记录-->

<insertid="insertStudent"parameterclass="Student">

insertintoSTUDENT(sid,sname,major,birth,score)

values(#sid#,#sname#,#major#,#birth#,#score#)

<!--

此处的#sid#不能写成#id#,因为此处没有getId()方法。

-->

</insert>

<!--删除指定id的记录-->

<deleteid="deleteStudentById"parameterclass="int">

deletefromSTUDENTwheresid=#sid#

<!--

此处的#sid#能写成#id#,因为只是作为参数传递的。

-->

</delete>

<!--修改记录-->

<updateid="updateStudent"parameterclass="Student">

updateSTUDENTset

sname=#sname#,

major=#major#,

birth=#birth#,

score=#score#

wheresid=#sid#

</update>

<!--模糊查询-->

<!--注意查询时的格式'%$...$%'-->

<selectid="selectStudentByName"parameterclass="String"resultclass="Student">

select*fromSTUDENT

wheresnamelike'%$sname$%'

</select>

<!--根据主键序列插入记录-->

<insertid="insertStudentBySequence"parameterclass="Student">

<selectKeyresultclass="int"keyProperty="sid">

selectstudentPKSequence.nextValfromdual

</selectKey>

insertintoSTUDENT(sid,sname,major,birth,score)

values(#sid#,#sname#,#major#,#birth#,#score#)

</insert>

</sqlMap>

4.编写实体类Student.java,其代码如下：

package com.ibatis;

import java.util.Date;

public class Student {

//要保证有无参数的构造方法

privateintsid;

privateStringsname;

privateStringmajor;

privateDatebirth;

privateStringscore;

publicDategetBirth(){

returnbirth;

}

publicvoidsetBirth(Datebirth){

this.birth=birth;

}

publicStringgetMajor(){

returnmajor;

}

publicvoidsetMajor(Stringmajor){

this.major=major;

}

publicStringgetScore(){

returnscore;

}

publicvoidsetScore(Stringscore){

this.score=score;

}

publicintgetSid(){

returnsid;

}

publicvoidsetSid(intsid){

this.sid=sid;

}

publicStringgetSname(){

returnsname;

}

publicvoidsetSname(Stringsname){

this.sname=sname;

}

publicStringtoString(){

Stringcontent="sid:"+sid+"\tsname:"+sname+"\tmajor:"+major+"\tbirth:"+birth+"\tscore:"+score;

returncontent;

}

}

5.编写dao文件，其代码如下：

package com.ibatis;

import java.util.List;

public interface IStudentDAO {

publicvoidaddStudent(Students);

publicvoidaddStudentBySequence(Students);

publicvoiddeleteStudentById(intid);

publicvoidupdateStudent(Students);

publicList<Student>queryAllStudent();

publicList<Student>queryStudentByName(Stringname);

publicStudentqueryStudentById(intid);

}

6.编写dao实现类文件，其代码如下：

package com.ibatis;

import java.io.IOException;

importjava.io.Reader;

importjava.sql.SQLException;

importjava.util.List;

import java.sql.Date;

import com.ibatis.common.resources.Resources;

importcom.ibatis.sqlmap.client.SqlMapClient;

import com.ibatis.sqlmap.client.SqlMapClientBuilder;

public class IStudentDAOImpl implements IStudentDAO {

private static SqlMapClient sqlMapClient = null;

static{

try{

Stringresource="com/ibatis/sqlMapConfig.xml";

Readerreader=Resources.getResourceAsReader(resource);

sqlMapClient=SqlMapClientBuilder.buildSqlMapClient(reader);

reader.close();

}catch(IOExceptione){

e.printStackTrace();

}

}

publicvoidaddStudent(Students){

//TODOAuto-generatedmethodstub

try{

sqlMapClient.insert("insertStudent",s);

}catch(SQLExceptione){

e.printStackTrace();

}

}

public void addStudentBySequence(Student s) {

//TODOAuto-generatedmethodstub

//step1:从数据库序列中获取主键值

//step2:插入

try{

sqlMapClient.insert("insertStudentBySequence",s);

//插入成功，打印出结果

System.out.println(s.getSid());

}catch(SQLExceptione){

e.printStackTrace();

}

}

public void deleteStudentById(int id) {

//TODOAuto-generatedmethodstub

try{

System.out.println(sqlMapClient.delete("deleteStudentById",id));

//删除操作返回影响的行数的数目

}catch(SQLExceptione){

e.printStackTrace();

}

}

public List<Student> queryAllStudent() {

List<Student>studentList=null;

try{

   studentList = sqlMapClient.queryForList("Student.selectAllStudent");

//当使用namespace时，必须指定如上的格式

}catch(SQLExceptione){

e.printStackTrace();

}

returnstudentList;

}

public Student queryStudentById(int id) {

//TODOAuto-generatedmethodstub

Students=null;

try{

s=(Student)sqlMapClient.queryForObject("selectStudentById",id);

}catch(SQLExceptione){

e.printStackTrace();

}

returns;

}

public List<Student> queryStudentByName(String name) {

//TODOAuto-generatedmethodstub

List<Student>studentList=null;

try{

studentList=sqlMapClient.queryForList("selectStudentByName",name);

}catch(SQLExceptione){

e.printStackTrace();

}

returnstudentList;

}

public void updateStudent(Student s) {

//TODOAuto-generatedmethodstub

try{

System.out.println(sqlMapClient.update("updateStudent",s));

//更改操作返回影响的行数的数目

}catch(SQLExceptione){

e.printStackTrace();

}

}

publicstaticvoidmain(String[]args){

IStudentDAOdao=newIStudentDAOImpl();

//删除指定id的学生

//dao.deleteStudentById(100);

//查询所有的学生

for(Studentstudent:dao.queryAllStudent()){

System.out.println(student);

}

//查询一个指定的学生

//System.out.println(dao.queryStudentById(1));

//增加一个学生

//Students=newStudent();

//s.setSid(100);

//s.setSname("li");

//s.setMajor("English");

//s.setBirth(Date.valueOf("2009-09-09"));

//s.setScore("90");

//dao.addStudent(s);

//更改学生

//Students=newStudent();

//s.setSid(1);

//s.setSname("li");

//s.setMajor("English");

//s.setBirth(Date.valueOf("2009-09-09"));

//s.setScore("90");

//dao.updateStudent(s);

//模糊查询

//for(Studentstudent:dao.queryStudentByName("i")){

//System.out.println(student);

//}

//通过序列插入数据

//Students=newStudent();

//s.setSid(1);

//s.setSname("li");

//s.setMajor("English");

//s.setBirth(Date.valueOf("2009-09-09"));

//s.setScore("90");

//   dao.addStudentBySequence(s);

}

}

短短几个文件，就构成了ibatis的简单应用，可以看到ibatis是轻量级的数据持久化方法，掌握也比较容易！