iBatis 简单介绍:
iBatis 是apache 的一个开源项目。一个O/R Mapping 解决方式,iBatis 最大的特点就是小巧。上手非常快。假设不须要太多复杂的功能。iBatis 是可以满足你的要求又足够灵活的最简单的解决方式,如今的iBatis 已经改名为Mybatis
了。
官网为:http://www.mybatis.org/
搭建iBatis 开发环境:
1 、导入相关的jar 包,ibatis-2.3.0.677.jar 、mysql-connector-java-5.1.6-bin.jar
2 、编写配置文件:
Jdbc 连接的属性文件 (eg:SqlMap.properties)
总配置文件 (SqlMapConfig.xml)
关于每一个实体的映射文件(Map 文件) (eg:Student.xml)
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本文以 对学生Student的 增删改查为例
Demo:
project文件夹:
数据库结构截图:
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1. Student.java
package com.ibatis.entity; import java.sql.Date; public class Student { // 注意这里须要保证有一个无參构造方法,由于包含Hibernate在内的映射都是使用反射的,假设没有无參构造可能会出现故障 private int id; private String name; private Date birth; private float score; public int getId() { return id; } public void setId(int id) { this.id = id; } public String getName() { return name; } public void setName(String name) { this.name = name; } public Date getBirth() { return birth; } public void setBirth(Date birth) { this.birth = birth; } public float getScore() { return score; } public void setScore(float score) { this.score = score; } @Override public String toString() { return "Student [id=" + id + ", name=" + name + ", birth=" + birth + ", score=" + score + "]"; } }2. SqlMap.properties
driver=com.mysql.jdbc.Driver url=jdbc:mysql://localhost:3306/mydb username=root password=1234563. 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> <!-- 通过typeAlias使得我们在以下使用Student实体类的时候不须要写包名 --> <typeAlias alias="Student" type="com.ibatis.entity.Student" /> <!-- 这样以后改了sql,就不须要去改java代码了 --> <!-- id表示select里的sql语句。resultClass表示返回结果的类型 --> <select id="selectAllStudent" resultClass="Student"> select * from tbl_student </select> <!-- parameterClass表示參数的内容 --> <!-- #表示这是一个外部调用的须要传进的參数,能够理解为占位符 --> <select id="selectStudentById" parameterClass="int" resultClass="Student"> select * from tbl_student where id=#id# </select> <!-- 注意这里的resultClass类型,使用Student类型取决于queryForList还是queryForObject --> <select id="selectStudentByName" parameterClass="String" resultClass="Student"> select name,birth,score from tbl_student where name like ‘%$name$%‘ </select> <insert id="addStudent" parameterClass="Student"> insert into tbl_student(name,birth,score) values (#name#,#birth#,#score#); <selectKey resultClass="int" keyProperty="id"> select @@identity as inserted <!-- 这里须要说明一下不同的数据库主键的生成,对各自的数据库有不同的方式: --> <!-- mysql:SELECT LAST_INSERT_ID() AS VALUE --> <!-- mssql:select @@IDENTITY as value --> <!-- oracle:SELECT STOCKIDSEQUENCE.NEXTVAL AS VALUE FROM DUAL --> <!-- 另一点须要注意的是不同的数据库生产商生成主键的方式不一样,有些是预先生成 (pre-generate)主键的,如Oracle和PostgreSQL。 有些是事后生成(post-generate)主键的,如MySQL和SQL Server 所以假设是Oracle数据库,则须要将selectKey写在insert之前 --> </selectKey> </insert> <delete id="deleteStudentById" parameterClass="int"> <!-- #id#里的id能够任意取,可是上面的insert则会有影响,由于上面的name会从Student里的属性里去查找 --> <!-- 我们也能够这样理解,假设有#占位符。则ibatis会调用parameterClass里的属性去赋值 --> delete from tbl_student where id=#id# </delete> <update id="updateStudent" parameterClass="Student"> update tbl_student set name=#name#,birth=#birth#,score=#score# where id=#id# </update> </sqlMap>4. 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> <!-- 引用JDBC属性的配置文件 --> <properties resource="com/ibatis/SqlMap.properties" /> <!-- 使用JDBC的事务管理 --> <transactionManager type="JDBC"> <!-- 数据源 --> <dataSource type="SIMPLE"> <property name="JDBC.Driver" value="${driver}" /> <property name="JDBC.ConnectionURL" value="${url}" /> <property name="JDBC.Username" value="${username}" /> <property name="JDBC.Password" value="${password}" /> </dataSource> </transactionManager> <!-- 这里能够写多个实体的映射文件 --> <sqlMap resource="com/ibatis/Student.xml" /> </sqlMapConfig>5. StudentDao.java
package com.ibatis.dao; import java.util.List; import com.ibatis.entity.Student; public interface StudentDao { /** * 加入学生信息 * * @param student * 学生实体 * @return 返回是否加入成功 */ public boolean addStudent(Student student); /** * 依据学生id删除学生信息 * * @param id * 学生id * @return 删除是否成功 */ public boolean deleteStudentById(int id); /** * 更新学生信息 * * @param student * 学生实体 * @return 更新是否成功 */ public boolean updateStudent(Student student); /** * 查询所有学生信息 * * @return 返回学生列表 */ public List<Student> selectAllStudent(); /** * 依据学生姓名模糊查询学生信息 * * @param name * 学生姓名 * @return 学生信息列表 */ public List<Student> selectStudentByName(String name); /** * 依据学生id查询学生信息 * * @param id * 学生id * @return 学生对象 */ public Student selectStudentById(int id); }6. StudentDaoImpl.java
package com.ibatis.daoimpl; import java.io.IOException; import java.io.Reader; import java.sql.SQLException; import java.util.List; import com.ibatis.dao.StudentDao; import com.ibatis.entity.Student; import com.ibatis.common.resources.Resources; import com.ibatis.sqlmap.client.SqlMapClient; import com.ibatis.sqlmap.client.SqlMapClientBuilder; public class StudentDaoImpl implements StudentDao { private static SqlMapClient sqlMapClient = null; // 读取配置文件 static { try { Reader reader = Resources .getResourceAsReader("com/ibatis/SqlMapConfig.xml"); sqlMapClient = SqlMapClientBuilder.buildSqlMapClient(reader); reader.close(); } catch (IOException e) { e.printStackTrace(); } } public boolean addStudent(Student student) { Object object = null; boolean flag = false; try { object = sqlMapClient.insert("addStudent", student); System.out.println("加入学生信息的返回值:" + object); } catch (SQLException e) { e.printStackTrace(); } if (object != null) { flag = true; } return flag; } public boolean deleteStudentById(int id) { boolean flag = false; Object object = null; try { object = sqlMapClient.delete("deleteStudentById", id); System.out.println("删除学生信息的返回值:" + object + "。这里返回的是影响的行数"); } catch (SQLException e) { e.printStackTrace(); } if (object != null) { flag = true; } return flag; } public boolean updateStudent(Student student) { boolean flag = false; Object object = false; try { object = sqlMapClient.update("updateStudent", student); System.out.println("更新学生信息的返回值:" + object + ",返回影响的行数"); } 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; } }7. TestIbatis.java
package com.ibatis.test; import java.sql.Date; import java.util.List; import com.ibatis.daoimpl.StudentDaoImpl; import com.ibatis.entity.Student; public class TestIbatis { public static void main(String[] args) { StudentDaoImpl studentDaoImpl = new StudentDaoImpl(); System.out.println("測试插入"); 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("測试依据id查询"); System.out.println(studentDaoImpl.selectStudentById(1)); System.out.println("測试模糊查询"); List<Student> mohuLists = studentDaoImpl.selectStudentByName("李"); for (Student student : mohuLists) { System.out.println(student); } System.out.println("測试查询全部"); List<Student> students = studentDaoImpl.selectAllStudent(); for (Student student : students) { System.out.println(student); } System.out.println("依据id删除学生信息"); System.out.println(studentDaoImpl.deleteStudentById(1)); System.out.println("測试更新学生信息"); 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 的优缺点:
长处:
1、 降低代码量,简单。
2、 性能增强。
3、 Sql
语句与程序代码分离。4、 增强了移植性。
缺点:
1、 和Hibernate 相比,sql 须要自己写;
2、 參数数量仅仅能有一个,多个參数时不太方便;
时间: 2024-10-17 15:01:23