Ibatis的使用

很多人都倾向于使用Hibernate，个人觉得，如果做个小项目的话，显得也比较的繁琐，Ibatis相对来说会更灵活一点。

下面就来介绍Ibatis的用法：

1、首先去下载Ibatis的jar包，https://code.google.com/p/mybatis/wiki/Downloads?tm=2，Ibatis从3.x开始就叫Mybatis了，新版本有很多更使用的改进，有兴趣的话可以去了解，我这里用的是ibatis-2.3.0.67版本的。

2、接下来就是配置属性文件和.xml文件了：

SqlMap.properties

driver=com.mysql.jdbc.Driver
url=jdbc:mysql://localhost:3306/test
username=ibatis
password=123456

 

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="cg/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>
	<!-- 这里可以写多个实体的映射文件 -->
	<sqlMap resource="cg/entity/Student.xml" />
</sqlMapConfig>

 

每个实体要建一个对应的xml文件

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使得我们在下面使用Student实体类的时候不需要写包名 -->
	<typeAlias alias="Student" type="cg.entity.Student" />

	<!-- 这样以后改了sql，就不需要去改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 student
	</select>

	<!-- parameterClass表示参数的内容 -->
	<!-- #表示这是一个外部调用的需要传进的参数，可以理解为占位符 -->
	<select id="selectStudentById" parameterClass="int" resultClass="Student">
		select * from student where id=#id#
	</select>
	
	<!-- 模糊查询 -->
	<select id="selectStudentByName" parameterClass="String" resultClass="Student">
		select id,name from student where name like '%$name$%'
	</select>
	
	<!-- 插入 -->
	<insert id="addStudent" parameterClass="Student">
		insert into student(name)
		 values(#name#);
		 <selectKey resultClass="int" keyProperty="id">
		 	select @@identity as inserted
		 	<!-- 这里需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 -->
			<!-- 还有一点需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 所以如果是Oracle数据库，则需要将selectKey写在insert之前 -->
		 </selectKey>
	</insert>
	
	<!-- 删除 -->
	<delete id="deleteStudentById" parameterClass="int">
	<!-- #id#里的id可以随意取，但是上面的insert则会有影响，因为上面的name会从Student里的属性里去查找 -->
		<!-- 我们也可以这样理解，如果有#占位符，则ibatis会调用parameterClass里的属性去赋值 -->
		delete from student where id=#id#
	</delete>
	
	
	<!-- 修改 -->
	<update id="updateStudent" parameterClass="Student">
		update student set name=#name# where id=#id#
	</update>
	
	<!-- 联表查询测试 -->
	<select id="selectCombine" parameterClass="int" resultClass="Student">
		select student.name,grade.grades from student,grade where student.id=grade.sid and grade.cid=#cid# 
	</select>
</sqlMap>

 实体类:Student.java

package cg.entity;

public class Student {
	private int id;
	private String name;
	private int cid;
	private int grades;
	
	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 int getCid() {
		return cid;
	}
	public void setCid(int cid) {
		this.cid = cid;
	}
	public int getGrades() {
		return grades;
	}
	public void setGrades(int grades) {
		this.grades = grades;
	}
	
}

 

测试类:TestIbatis.java

package cg.test;

import java.io.IOException;
import java.io.Reader;
import java.sql.SQLException;
import java.util.Iterator;
import java.util.List;

import cg.entity.Student;

import com.ibatis.common.resources.Resources;
import com.ibatis.sqlmap.client.SqlMapClient;
import com.ibatis.sqlmap.client.SqlMapClientBuilder;

public class TestIbatis {
	private static SqlMapClient sqlMapClient = null;
	static{
		Reader reader;
		try {
			reader = Resources.getResourceAsReader("SqlMapConfig.xml");
			sqlMapClient = SqlMapClientBuilder.buildSqlMapClient(reader);
			reader.close();
		} catch (IOException e) {
			e.printStackTrace();
		}
	}
	
	
	
	
	public List<Student> queryAllStudent() throws SQLException{
		List<Student> studentList = null;
		studentList = sqlMapClient.queryForList("selectAllStudent");
		return studentList;
	}
	
	
	
	public Student queryStudentById(int id) throws SQLException{
		Student s = new Student();
		s = (Student) sqlMapClient.queryForObject("selectStudentById", id);
		return s;
	}
	
	
	public Student queryStudentByName(String name) throws SQLException{
		Student s = new Student();
		s = (Student) sqlMapClient.queryForObject("selectStudentByName", name);
		return s;
	}
	
	
	public boolean insert(Student s){
		Object o = null;
		boolean flag = false;
		try {
			o = sqlMapClient.insert("addStudent", s);
			System.out.println("添加信息返回的值:"+o);
		} catch (SQLException e) {
			e.printStackTrace();
		}
		
		if(o != null){
			flag = true;
		}
		
		return flag;
	}
	
	
	public boolean deleteStudentById(int id){
		boolean flag = false;
		Object o = null;
		try {
			o = sqlMapClient.delete("deleteStudentById", id);
			System.out.println("删除学生信息返回的值:"+o+"这里返回的是受影响的行数");
		} catch (SQLException e) {
			e.printStackTrace();
		}
		if(o != null){
			flag = true;
		}
		
		return flag;
	}
	
	
	public boolean updateStudentById(Student s){
		boolean flag = false;
		Object o = null;
		try {
			o = sqlMapClient.update("updateStudent", s);
			System.out.println("返回的值为:"+o);
		} catch (SQLException e) {
			e.printStackTrace();
		}
		
		if(o != null){
			flag = true;
		}
		return flag;
	}
	
	
	
	
	public static void main(String[] args){
		TestIbatis t = new TestIbatis();
		
		//测试全部查询
		//		try {
//			Student s = t.queryStudentById(1);
//			System.out.println(s.getName());
//			List<Student> stlist = t.queryAllStudent();
//			Iterator<Student> it = stlist.iterator();
//			while(it.hasNext()){
//				Student st = it.next();
//				System.out.println(st.getName());
//			}
//		} catch (SQLException e) {
//			e.printStackTrace();
//		}
	    
		
		//测试模糊查询	
//		try {
//			System.out.println(t.queryStudentByName("刘").getName());
//		} catch (SQLException e) {
//			e.printStackTrace();
//		}
		
		
		//测试添加
//		Student s = new Student();
//		s.setName("刘诗诗");
//		System.out.println(t.insert(s));
		
		//测试删除
//		System.out.println(t.deleteStudentById(5));
		
		
		//测试更新
		Student s = new Student();
		s.setName("诗诗");
		s.setId(6);
		System.out.println(t.updateStudentById(s));
	}
}	

 

测试联表查询的类：TestIbatis2.java

package cg.test;

import java.io.IOException;
import java.io.Reader;
import java.sql.SQLException;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.LinkedHashMap;
import java.util.List;
import java.util.Map;

import cg.entity.Student;

import com.ibatis.common.resources.Resources;
import com.ibatis.sqlmap.client.SqlMapClient;
import com.ibatis.sqlmap.client.SqlMapClientBuilder;

public class TestIbatis2 {
	
	private static SqlMapClient sqlMapClient = null;
	
	static{
		try {
			Reader reader = Resources.getResourceAsReader("SqlMapConfig.xml");
			sqlMapClient = SqlMapClientBuilder.buildSqlMapClient(reader);
			reader.close();
		} catch (IOException e) {
			e.printStackTrace();
		}
	}
	
	
	
	//联表查询
	public List<Student> queryList(int cid){
		List<Student> stuList = null;
		try {
			stuList = sqlMapClient.queryForList("selectCombine", cid);
			
		} catch (SQLException e) {
			e.printStackTrace();
		}
		
		return stuList;
	}
	
	
	public List<Map<Object,Object>> toList(List<Student> list){
		Iterator<Student> it = list.iterator();
		List<Map<Object,Object>> mapList = new ArrayList<Map<Object,Object>>();
		while(it.hasNext()){
			Student stu = it.next();
			Map m = new LinkedHashMap();
			m.put("x", stu.getName());
			m.put("y", stu.getGrades());
			mapList.add(m);
		}
		
		return mapList;
	}
	
	
	
	
	
	public static void main(String[] args){
		TestIbatis2 t = new TestIbatis2();
		List<Student> stuList = t.queryList(1);
		Iterator<Student> it = stuList.iterator();
		while(it.hasNext()){
			Student stu = it.next();
			System.out.println("姓名:"+stu.getName()+"   ,成绩:"+stu.getGrades());
		}
		
		
		System.out.println(t.toList(t.queryList(1)).size());
	}
}