Ibatis学习例子

iBatis 简介：

iBatis 是apache 的一个开源项目，一个O/R Mapping 解决方案，iBatis 最大的特点就是小巧，上手很快。如果不需要太多复杂的功能，iBatis 是能够满足你的要求又足够灵活的最简单的解决方案，现在的iBatis 已经改名为Mybatis 了。

iBatis 让你能够更好的在JAVA应用中设计和实现实体层。这个框架有两个主要的组成部分，一个是SQL Maps，另一个是Data Access Objects。 

SQL Maps：

Sql Maps是这个框架中最激动人心的部分，它是整个iBATIS Database Layer的核心价值所在。通过使用Sql Maps你可以显著的节约数据库操作的代码量。SQL Maps使用一个简单的XML文件来实现从javaBean到SQL statements的映射。跟其他的框架或者对象映射工具相比，SQL Maps最大的优势是简单。它需要学习的东西很少，在连接表或复杂查询时也不需要复杂的scheme(怎么翻complex scheme?)，使用SQL Maps， 你可以自由的使用SQL语句。

Data Access Objects (DAO)

当我们开发灵活的JAVA应用时，有一个好主意就是通过一个通用API层把实体操作的细节封装起来。Data Access Objects允许你通过一个简单接口的来操作数据，从而隐藏了实现的细节。使用DAO，你可以动态配置你的应用程序来访问不同的实体存储机制。如果你有 一个复杂的应用需要用到几个不同的数据库，DAO可以让你建立一个一致的API，让系统的其他部分来调用。

工作流程：

SQL Maps提供一个简单的框架，通过XML描述来映射JAVABeans，MAP implementations甚至原始类型的包装(String,Integer等)到JDBC PreparedStatement。想法很简单，基本的步骤如下：

1) 提供一个对象作为参数(either a JavaBean, Map or primitive wrapper)，The parameter object will be used setting input values in an update statement, or query values in a where clause (etc.).(感觉不译为好，你说呢？)

2) 执行这个映射的statement，这一步是魔术发生的地方。SQL Maps框架将建立一个PreparedStatement实例(instance)，使用前面提供的对象的参数，执行statement，然后从ResultSet中建立一个返回对象。

3) 如果是Update，则返回有多少行修改了，如果是查询，则返回一个对象或者对象的集合。跟参数一样，返回对象也可以是一个JAVABEAN，MAP或者一个primitive type wrapper。

官网为：http://www.mybatis.org/

Demo ：

下面是我的工程图样：

1.建立MyConst.java，其主要用来编写静态变量

package com.tinytinysun.consts;

public final class MyConst {
	public static final int int_value0 = 0;
	public static final int int_value1 = 1;
	
	public static final String str_space = "";
	public static final String str_space_1 = " ";
}

2.建立Student.java，这个是模型文件，数据库存在和它对应的表

   说明：由于待会需要输出数据库表的信息，所以在这里重写了toString()这个方法

package com.tinytinysun.model;

import com.tinytinysun.consts.MyConst;

public class Student {
	private int id = MyConst.int_value0;
	private String name = MyConst.str_space;
	private String address = MyConst.str_space;

	public Student() {
	}	

	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 String getAddress() {
		return address;
	}

	public void setAddress(String address) {
		this.address = address;
	}

	@Override
	public String toString() {
		StringBuffer buffer = new StringBuffer();
		buffer.append("id:");
		buffer.append(id);
		buffer.append(MyConst.str_space_1);
		buffer.append(MyConst.str_space_1);
		buffer.append("name:");
		buffer.append(name);
		buffer.append(MyConst.str_space_1);
		buffer.append(MyConst.str_space_1);
		buffer.append("address:");
		buffer.append(address);
		return buffer.toString();
	}
}

 
 3.建立StudentDao.java这个接口，用于声明对数据库操作的方法

package com.tinytinysun.dao;

import java.util.List;
import com.tinytinysun.model.Student;

public interface StudentDao {
	//通过ID查询数据库
	public Student selectStudentById(int id);
	//查询数据库Student这个表的所有数据
	public List<Student> selectAllStudent();
	//增加一条记录
	public int addStudent(Student student);
	//通过ID删除某条记录
	public int delectStudentById(int id);
	//更新一条记录
	public int updateStudent(Student student);

}

4.建立StudentDaoImpl.java，该类为上3接口的实现类

package com.tinytinysun.dao.impl;

import java.sql.SQLException;
import java.util.List;
import com.ibatis.sqlmap.client.SqlMapClient;
import com.tinytinysun.consts.MyConst;
import com.tinytinysun.dao.StudentDao;
import com.tinytinysun.dbConfig.MySqlConfig;
import com.tinytinysun.model.Student;

public class StudentDaoImpl implements StudentDao{

	SqlMapClient client = MySqlConfig.getSqlMapClient();
	
	@Override
	public int addStudent(Student student) {
		System.out.println("插入数据");
		Object oRows = null;
		Integer iRows = null;
		int rows = MyConst.int_value0;
		try {
			oRows = client.insert("insertStudent", student);
		} catch (SQLException e) {
			e.printStackTrace();
		}
		if(oRows == null){
			return MyConst.int_value0;
		}else{
			iRows = (Integer)oRows;
			rows = iRows.intValue();
			System.out.println("成功插入 " + rows + " 条数据");
			return rows;
		}
	}

	@Override
	public int delectStudentById(int id) {
		System.out.println("删除数据");
		int rows = MyConst.int_value0;
		try {
			rows = client.delete("delectStudentById", id);
		} catch (SQLException e) {
			e.printStackTrace();
		}
		System.out.println("成功删除 " + rows + " 条数据");
		return rows;
	}

	@Override
	public List<Student> selectAllStudent() {
		System.out.println("查询所有数据");
		List<Student> list = null;
		try {
			list = client.queryForList("getStudent");
		} catch (SQLException e) {
			e.printStackTrace();
		}
		return list;
	}

	@Override
	public Student selectStudentById(int id) {
		System.out.println("通过ID查询数据");
		Student student = null;
		try {
			student = (Student)client.queryForObject("selectStudentById", id);
		} catch (SQLException e) {
			e.printStackTrace();
		}
		return student;
	}

	@Override
	public int updateStudent(Student student) {
		System.out.println("更新数据");
		int rows = MyConst.int_value0;
		try {
			rows = client.update("updateStudent", student);
		} catch (SQLException e) {
			e.printStackTrace();
		}
		System.out.println("成功更新数据 " + rows + " 条数据");
		return rows;
	}
}

5.建立SqlMapConfig.properties文件，主要用于存储数据库的配置信息

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

6.建立SqlMapConfig.xml文件，它是总配置文件

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE sqlMapConfig PUBLIC "-//iBATIS.com//DTD SQL Map Config 2.0//EN" "http://www.ibatis.com/dtd/sql-map-config-2.dtd"> 

<sqlMapConfig> 
	<properties resource="com/tinytinysun/dbConfig/SqlMapConfig.properties" />
	<transactionManager type="JDBC">
		<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>
	<sqlMap resource="com/tinytinysun/model/Student.xml"/>
</sqlMapConfig>

7.建立MySqlConfig.java

package com.tinytinysun.dbConfig;

import java.io.IOException;
import java.io.Reader;
import com.ibatis.common.resources.Resources;
import com.ibatis.sqlmap.client.SqlMapClient;
import com.ibatis.sqlmap.client.SqlMapClientBuilder;

public class MySqlConfig {
	private static SqlMapClient client ;
	static {
		String resource = "com/tinytinysun/dbConfig/SqlMapConfig.xml";
		try {
			Reader reader = Resources.getResourceAsReader(resource);
			client = SqlMapClientBuilder.buildSqlMapClient(reader);
			reader.close();
		} catch (IOException e) {
			e.printStackTrace();
		}
	}
	
	public static SqlMapClient getSqlMapClient(){
		return client;
	} 
}

8.建立Student.xml

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE sqlMap PUBLIC "-//iBATIS.com//DTD SQL Map 2.0//EN" "http://www.ibatis.com/dtd/sql-map-2.dtd">

<sqlMap namespace="Student">
	<typeAlias alias="student" type="com.tinytinysun.model.Student" />
	<select id="getStudent" resultClass="student">
		select * from Student
	</select>
	<select id="selectStudentById" parameterClass="int" resultClass="student">
		select * from Student where id =#id#
	</select>
	<insert id="insertStudent" parameterClass="student">
		insert into Student(id,name,address) value(#id#,#name#,#address#)
	</insert>
	<delete id="delectStudentById" parameterClass="int">
		delete from Student where id = #id#
	</delete>
	<update id="updateStudent" parameterClass="student">
		update Student set name=#name# ,address=#address# where id = #id# 
	</update>
</sqlMap>

9.建立MyTest.java测试文件

package com.tinytinysun.test;

import java.util.List;
import com.tinytinysun.consts.MyConst;
import com.tinytinysun.dao.StudentDao;
import com.tinytinysun.dao.impl.StudentDaoImpl;
import com.tinytinysun.model.Student;

public class MyTest {

	public static void main(String[] args) {
		Student student = null;
		StudentDao studentDao = new StudentDaoImpl();
		int flg = MyConst.int_value0;
		
		// 查询所有的数据
		List<Student> studentList = studentDao.selectAllStudent();
		if (studentList != null) {
			for (Student tempStudent : studentList) {
				System.out.println(tempStudent.toString());
				if(tempStudent.getId() > flg){
					flg = tempStudent.getId();
				}
			}
		}
		System.out.println();
		
		// 通过ID查找数据
		student = studentDao.selectStudentById(1);
		System.out.println(student);
		System.out.println();
		
		
		// 插入一条数据
		student = new Student();
		student.setId(flg + MyConst.int_value1);
		student.setName("name" + (flg + MyConst.int_value1));
		student.setAddress("address" + (flg + MyConst.int_value1));
		studentDao.addStudent(student);
		System.out.println();
		if(flg == MyConst.int_value0){
			student.setId(flg + MyConst.int_value1 + MyConst.int_value1);
			studentDao.addStudent(student);
			System.out.println();
		}
		
		// 删除一条数据 
		if(flg != MyConst.int_value0){
			studentDao.delectStudentById(flg);
			System.out.println();
		}
		
		// 更新数据
		student.setName("uName" + (flg + MyConst.int_value1));
		student.setName("uAddress" + (flg + MyConst.int_value1));
		studentDao.updateStudent(student);
	}
}

10.由于我使用了log4j这个插件，所以加入log4j.properties这个配置文件

log4j.rootLogger=DEBUG, stdout, fileout
log4j.logger.com.fiscal = DEBUG
log4j.logger.com.system = DEBUG
log4j.logger.com.ibatis = DEBUG
log4j.logger.com.ibatis.common.jdbc.SimpleDataSource = DEBUG
log4j.logger.com.ibatis.common.jdbc.ScriptRunner = DEBUG
log4j.logger.com.ibatis.sqlmap.engine.impl.SqlMapClientDelegate = DEBUG
log4j.logger.java.sql.Connection = DEBUG
log4j.logger.java.sql.ResultSet = DEBUG
log4j.appender.stdout=org.apache.log4j.ConsoleAppender
log4j.appender.fileout=org.apache.log4j.RollingFileAppender
log4j.appender.fileout.File=C\:\\ibatis.log
log4j.appender.fileout.MaxFileSize=10000KB
log4j.appender.stdout.layout=org.apache.log4j.PatternLayout
log4j.appender.stdout.layout.ConversionPattern=[%-5p] %d{yyyy-MM-dd HH:mm:ss} :%m%n
log4j.appender.fileout.layout=org.apache.log4j.PatternLayout
log4j.appender.fileout.layout.ConversionPattern=[%-5p]_%d{yyyy-MM-dd HH\:mm\:ss} \:%m%n

最后开始测试了：

查询所有数据
[DEBUG] 2013-03-19 23:30:02 :Created connection 17547166.
[DEBUG] 2013-03-19 23:30:02 :{conn-100000} Connection
[DEBUG] 2013-03-19 23:30:02 :{conn-100000} Preparing Statement:    select * from Student  
[DEBUG] 2013-03-19 23:30:02 :{pstm-100001} Executing Statement:    select * from Student  
[DEBUG] 2013-03-19 23:30:02 :{pstm-100001} Parameters: []
[DEBUG] 2013-03-19 23:30:02 :{pstm-100001} Types: []
[DEBUG] 2013-03-19 23:30:02 :{rset-100002} ResultSet
[DEBUG] 2013-03-19 23:30:02 :Returned connection 17547166 to pool.

通过ID查询数据
[DEBUG] 2013-03-19 23:30:02 :Checked out connection 17547166 from pool.
[DEBUG] 2013-03-19 23:30:02 :{conn-100003} Connection
[DEBUG] 2013-03-19 23:30:02 :{conn-100003} Preparing Statement:    select * from Student where id =?  
[DEBUG] 2013-03-19 23:30:02 :{pstm-100004} Executing Statement:    select * from Student where id =?  
[DEBUG] 2013-03-19 23:30:02 :{pstm-100004} Parameters: [1]
[DEBUG] 2013-03-19 23:30:02 :{pstm-100004} Types: [java.lang.Integer]
[DEBUG] 2013-03-19 23:30:02 :{rset-100005} ResultSet
[DEBUG] 2013-03-19 23:30:02 :Returned connection 17547166 to pool.
null

插入数据
[DEBUG] 2013-03-19 23:30:02 :Checked out connection 17547166 from pool.
[DEBUG] 2013-03-19 23:30:02 :{conn-100006} Connection
[DEBUG] 2013-03-19 23:30:02 :{conn-100006} Preparing Statement:    insert into Student(id,name,address) value(?,?,?)  
[DEBUG] 2013-03-19 23:30:02 :{pstm-100007} Executing Statement:    insert into Student(id,name,address) value(?,?,?)  
[DEBUG] 2013-03-19 23:30:02 :{pstm-100007} Parameters: [1, name1, address1]
[DEBUG] 2013-03-19 23:30:02 :{pstm-100007} Types: [java.lang.Integer, java.lang.String, java.lang.String]
[DEBUG] 2013-03-19 23:30:02 :Returned connection 17547166 to pool.

插入数据
[DEBUG] 2013-03-19 23:30:02 :Checked out connection 17547166 from pool.
[DEBUG] 2013-03-19 23:30:02 :{conn-100008} Connection
[DEBUG] 2013-03-19 23:30:02 :{conn-100008} Preparing Statement:    insert into Student(id,name,address) value(?,?,?)  
[DEBUG] 2013-03-19 23:30:02 :{pstm-100009} Executing Statement:    insert into Student(id,name,address) value(?,?,?)  
[DEBUG] 2013-03-19 23:30:02 :{pstm-100009} Parameters: [2, name1, address1]
[DEBUG] 2013-03-19 23:30:02 :{pstm-100009} Types: [java.lang.Integer, java.lang.String, java.lang.String]
[DEBUG] 2013-03-19 23:30:02 :Returned connection 17547166 to pool.

更新数据
[DEBUG] 2013-03-19 23:30:02 :Checked out connection 17547166 from pool.
[DEBUG] 2013-03-19 23:30:02 :{conn-100010} Connection
[DEBUG] 2013-03-19 23:30:02 :{conn-100010} Preparing Statement:    update Student set name=? ,address=? where id = ?   
[DEBUG] 2013-03-19 23:30:02 :{pstm-100011} Executing Statement:    update Student set name=? ,address=? where id = ?   
[DEBUG] 2013-03-19 23:30:02 :{pstm-100011} Parameters: [uAddress1, address1, 2]
[DEBUG] 2013-03-19 23:30:02 :{pstm-100011} Types: [java.lang.String, java.lang.String, java.lang.Integer]
[DEBUG] 2013-03-19 23:30:02 :Returned connection 17547166 to pool.
成功更新数据 1 条数据