iBatis简单入门教程
iBatis 簡介:
iBatis 是apache 的一個開源項目,一個O/R Mapping 解決方案,iBatis 最大的特點就是小巧,上手很快。如果不需要太多復(fù)雜的功能,iBatis 是能夠滿足你的要求又足夠靈活的最簡單的解決方案,現(xiàn)在的iBatis 已經(jīng)改名為Mybatis 了。
官網(wǎng)為:http://www.mybatis.org/
搭建iBatis 開發(fā)環(huán)境:
1 、導(dǎo)入相關(guān)的jar 包,ibatis-2.3.0.677.jar 、mysql-connector-java-5.1.6-bin.jar
2 、編寫配置文件:
Jdbc 連接的屬性文件
關(guān)于每個實體的映射文件(Map 文件)
Demo :
Student.java:
- package com.iflytek.entity;
- import java.sql.Date;
- /**
- * @author xudongwang 2011-12-31
- *
- * Email:[email protected]
- *
- */
- publicclass Student {
- // 注意這里需要保證有一個無參構(gòu)造方法,因為包括Hibernate在內(nèi)的映射都是使用反射的,如果沒有無參構(gòu)造可能會出現(xiàn)問題
- privateint id;
- private String name;
- private Date birth;
- privatefloat score;
- publicint getId() {
- return id;
- }
- publicvoid setId(int id) {
- this.id = id;
- }
- public String getName() {
- return name;
- }
- publicvoid setName(String name) {
- this.name = name;
- }
- public Date getBirth() {
- return birth;
- }
- publicvoid setBirth(Date birth) {
- this.birth = birth;
- }
- publicfloat getScore() {
- return score;
- }
- publicvoid setScore(float score) {
- this.score = score;
- }
- @Override
- public String toString() {
- return"id=" + id + "\tname=" + name + "\tmajor=" + birth + "\tscore="
- + score + "\n";
- }
- }
SqlMap.properties :
- driver=com.mysql.jdbc.Driver
- url=jdbc:mysql://localhost:3306/ibatis
- username=root
- password=123
Student.xml :
- <?xmlversion="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>
- <!-- 通過typeAlias使得我們在下面使用Student實體類的時候不需要寫包名 -->
- <typeAliasalias="Student"type="com.iflytek.entity.Student"/>
- <!-- 這樣以后改了sql,就不需要去改java代碼了 -->
- <!-- id表示select里的sql語句,resultClass表示返回結(jié)果的類型 -->
- <selectid="selectAllStudent"resultClass="Student">
- select * from
- tbl_student
- </select>
- <!-- parameterClass表示參數(shù)的內(nèi)容 -->
- <!-- #表示這是一個外部調(diào)用的需要傳進的參數(shù),可以理解為占位符 -->
- <selectid="selectStudentById"parameterClass="int"resultClass="Student">
- select * from tbl_student where id=#id#
- </select>
- <!-- 注意這里的resultClass類型,使用Student類型取決于queryForList還是queryForObject -->
- <selectid="selectStudentByName"parameterClass="String"
- resultClass="Student">
- select name,birth,score from tbl_student where name like
- '%$name$%'
- </select>
- <insertid="addStudent"parameterClass="Student">
- insert into
- tbl_student(name,birth,score) values
- (#name#,#birth#,#score#)
- <selectKeyresultClass="int"keyProperty="id">
- select @@identity as inserted
- <!-- 這里需要說明一下不同的數(shù)據(jù)庫主鍵的生成,對各自的數(shù)據(jù)庫有不同的方式: -->
- <!-- mysql:SELECT LAST_INSERT_ID() AS VALUE -->
- <!-- mssql:select @@IDENTITY as value -->
- <!-- oracle:SELECT STOCKIDSEQUENCE.NEXTVAL AS VALUE FROM DUAL -->
- <!-- 還有一點需要注意的是不同的數(shù)據(jù)庫生產(chǎn)商生成主鍵的方式不一樣,有些是預(yù)先生成 (pre-generate)主鍵的,如Oracle和PostgreSQL。
- 有些是事后生成(post-generate)主鍵的,如MySQL和SQL Server 所以如果是Oracle數(shù)據(jù)庫,則需要將selectKey寫在insert之前 -->
- </selectKey>
- </insert>
- <deleteid="deleteStudentById"parameterClass="int">
- <!-- #id#里的id可以隨意取,但是上面的insert則會有影響,因為上面的name會從Student里的屬性里去查找 -->
- <!-- 我們也可以這樣理解,如果有#占位符,則ibatis會調(diào)用parameterClass里的屬性去賦值 -->
- delete from tbl_student where id=#id#
- </delete>
- <updateid="updateStudent"parameterClass="Student">
- update tbl_student set
- name=#name#,birth=#birth#,score=#score# where id=#id#
- </update>
- </sqlMap>
說明:
如果xml 中沒有ibatis 的提示,則window --> Preference--> XML-->XML Catalog---> 點擊add
選擇uri URI: 請選擇本地文件系統(tǒng)上
iBatisDemo1/WebContent/WEB-INF/lib/sql-map-config-2.dtd 文件;
Key Type: 選擇Schema Location;
Key: 需要聯(lián)網(wǎng)的,不建議使用;
SqlMapConfig.xml :
- <?xmlversion="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>
- <!-- 引用JDBC屬性的配置文件 -->
- <propertiesresource="com/iflytek/entity/SqlMap.properties"/>
- <!-- 使用JDBC的事務(wù)管理 -->
- <transactionManagertype="JDBC">
- <!-- 數(shù)據(jù)源 -->
- <dataSourcetype="SIMPLE">
- <propertyname="JDBC.Driver"value="${driver}"/>
- <propertyname="JDBC.ConnectionURL"value="${url}"/>
- <propertyname="JDBC.Username"value="${username}"/>
- <propertyname="JDBC.Password"value="${password}"/>
- </dataSource>
- </transactionManager>
- <!-- 這里可以寫多個實體的映射文件 -->
- <sqlMapresource="com/iflytek/entity/Student.xml"/>
- </sqlMapConfig>
StudentDao :
- package com.iflytek.dao;
- import java.util.List;
- import com.iflytek.entity.Student;
- /**
- * @author xudongwang 2011-12-31
- *
- * Email:[email protected]
- *
- */
- publicinterface StudentDao {
- /**
- * 添加學(xué)生信息
- *
- * @param student
- * 學(xué)生實體
- * @return 返回是否添加成功
- */
- publicboolean addStudent(Student student);
- /**
- * 根據(jù)學(xué)生id刪除學(xué)生信息
- *
- * @param id
- * 學(xué)生id
- * @return 刪除是否成功
- */
- publicboolean deleteStudentById(int id);
- /**
- * 更新學(xué)生信息
- *
- * @param student
- * 學(xué)生實體
- * @return 更新是否成功
- */
- publicboolean updateStudent(Student student);
- /**
- * 查詢?nèi)繉W(xué)生信息
- *
- * @return 返回學(xué)生列表
- */
- public List<Student> selectAllStudent();
- /**
- * 根據(jù)學(xué)生姓名模糊查詢學(xué)生信息
- *
- * @param name
- * 學(xué)生姓名
- * @return 學(xué)生信息列表
- */
- public List<Student> selectStudentByName(String name);
- /**
- * 根據(jù)學(xué)生id查詢學(xué)生信息
- *
- * @param id
- * 學(xué)生id
- * @return 學(xué)生對象
- */
- public Student selectStudentById(int id);
- }
StudentDaoImpl :
- package com.iflytek.daoimpl;
- import java.io.IOException;
- import java.io.Reader;
- import java.sql.SQLException;
- import java.util.List;
- import com.ibatis.common.resources.Resources;
- import com.ibatis.sqlmap.client.SqlMapClient;
- import com.ibatis.sqlmap.client.SqlMapClientBuilder;
- import com.iflytek.dao.StudentDao;
- import com.iflytek.entity.Student;
- /**
- * @author xudongwang 2011-12-31
- *
- * Email:[email protected]
- *
- */
- publicclass StudentDaoImpl implements StudentDao {
- privatestatic SqlMapClient sqlMapClient = null;
- // 讀取配置文件
- static {
- try {
- Reader reader = Resources
- .getResourceAsReader("com/iflytek/entity/SqlMapConfig.xml");
- sqlMapClient = SqlMapClientBuilder.buildSqlMapClient(reader);
- reader.close();
- } catch (IOException e) {
- e.printStackTrace();
- }
- }
- publicboolean addStudent(Student student) {
- Object object = null;
- boolean flag = false;
- try {
- object = sqlMapClient.insert("addStudent", student);
- System.out.println("添加學(xué)生信息的返回值:" + object);
- } catch (SQLException e) {
- e.printStackTrace();
- }
- if (object != null) {
- flag = true;
- }
- return flag;
- }
- publicboolean deleteStudentById(int id) {
- boolean flag = false;
- Object object = null;
- try {
- object = sqlMapClient.delete("deleteStudentById", id);
- System.out.println("刪除學(xué)生信息的返回值:" + object + ",這里返回的是影響的行數(shù)");
- } catch (SQLException e) {
- e.printStackTrace();
- }
- if (object != null) {
- flag = true;
- }
- return flag;
- }
- publicboolean updateStudent(Student student) {
- boolean flag = false;
- Object object = false;
- try {
- object = sqlMapClient.update("updateStudent", student);
- System.out.println("更新學(xué)生信息的返回值:" + object + ",返回影響的行數(shù)");
- } catch (SQLException e) {
- e.printStackTrace();
- }
- if (object != null) {
- flag = true;
- }
- return flag;
- }
- public List<Student> selectAllStudent() {
- List<Student> students = null;
- try {
- students = sqlMapClient.queryForList("selectAllStudent");
- } catch (SQLException e) {
- e.printStackTrace();
- }
- return students;
- }
- public List<Student> selectStudentByName(String name) {
- List<Student> students = null;
- try {
- students = sqlMapClient.queryForList("selectStudentByName",name);
- } catch (SQLException e) {
- e.printStackTrace();
- }
- return students;
- }
- public Student selectStudentById(int id) {
- Student student = null;
- try {
- student = (Student) sqlMapClient.queryForObject(
- "selectStudentById", id);
- } catch (SQLException e) {
- e.printStackTrace();
- }
- return student;
- }
- }
TestIbatis.java :
- package com.iflytek.test;
- import java.sql.Date;
- import java.util.List;
- import com.iflytek.daoimpl.StudentDaoImpl;
- import com.iflytek.entity.Student;
- /**
- * @author xudongwang 2011-12-31
- *
- * Email:[email protected]
- *
- */
- publicclass TestIbatis {
- publicstaticvoid main(String[] args) {
- StudentDaoImpl studentDaoImpl = new StudentDaoImpl();
- System.out.println("測試插入");
- Student addStudent = new Student();
- addStudent.setName("李四");
- addStudent.setBirth(Date.valueOf("2011-09-02"));
- addStudent.setScore(88);
- System.out.println(studentDaoImpl.addStudent(addStudent));
- System.out.println("測試根據(jù)id查詢");
- System.out.println(studentDaoImpl.selectStudentById(1));
- System.out.println("測試模糊查詢");
- List<Student> mohuLists = studentDaoImpl.selectStudentByName("李");
- for (Student student : mohuLists) {
- System.out.println(student);
- }
- System.out.println("測試查詢所有");
- List<Student> students = studentDaoImpl.selectAllStudent();
- for (Student student : students) {
- System.out.println(student);
- }
- System.out.println("根據(jù)id刪除學(xué)生信息");
- System.out.println(studentDaoImpl.deleteStudentById(1));
- System.out.println("測試更新學(xué)生信息");
- Student updateStudent = new Student();
- updateStudent.setId(1);
- updateStudent.setName("李四1");
- updateStudent.setBirth(Date.valueOf("2011-08-07"));
- updateStudent.setScore(21);
- System.out.println(studentDaoImpl.updateStudent(updateStudent));
- }
- }
iBatis 的優(yōu)缺點:
優(yōu)點:
1、減少代碼量,簡單;
2、性能增強;
3、Sql 語句與程序代碼分離;
4、增強了移植性;
缺點:
1、和Hibernate 相比,sql 需要自己寫;
2、參數(shù)數(shù)量只能有一個,多個參數(shù)時不太方便;