Mybatis使用篇之二：HelloWorld

1. 搭建开发环境

（1）新建一个Web工程，名称为MybatisFramework。

 

（2）将以下的JAR放到Web工程的lib下面：

mybatis-3.0.6.jar
og4j-1.2.16.jar
classes12.jar

 

（3）在src下面新建log4j.properties文件，该文件的内容如下：

log4j.appender.stdout=org.apache.log4j.ConsoleAppender
log4j.appender.stdout.layout=org.apache.log4j.PatternLayout
log4j.appender.stdout.layout.ConversionPattern=%d %p [%c] -%m%n
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.Statement=debug
log4j.logger.java.sql.PreparedStatement=debug,stdout

 

（4）在src下面新建mybatis.cfg.xml文件，该文件的内容如下：

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

<!DOCTYPE configuration PUBLIC 
    "-//mybatis.org//DTD Config 3.0//EN"
    "http://mybatis.org/dtd/mybatis-3-config.dtd">

<configuration>
    
    <environments default="development">
        <environment id="development">
            <transactionManager type="JDBC" />
            <dataSource type="POOLED">
              <property name="driver" value="oracle.jdbc.OracleDriver" />
              <property name="url" value="jdbc:oracle:thin:@localhost:1521:SID" />
              <property name="username" value="xxxx" />
              <property name="password" value="xxxx" />
            </dataSource>
        </environment>
    </environments>
   
    </configuration>

 

 

2. 入门示例

（1）在Oracle数据库执行以下SQL，创建一个USER_INFO的表：

-- Create table
create table USER_INFO
(
  ID          NUMBER(12) not null,
  NAME        VARCHAR2(50)
);

--Insert data
insert into USER_INFO(ID,NAME) values(1,'张三');

 

（2）新建一个Java类UserInfo.java，该类的内容如下：

 

package com.user;

public class UserInfo {
	private int id;
	private String name;

	public UserInfo() {
	}

	public UserInfo(String name) {
		this(0, name);
	}

	public UserInfo(int id, String name) {
		this.id = id;
		this.name = name;
	}

	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;
	}

	@Override
	public String toString() {
		return "ID: " + id + ", Name: " + name;
	}
}

 

（3）在com.user.sqlmap下面新建UserInfo.xml文件，该文件的内容如下：

 

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

<!DOCTYPE mapper PUBLIC 
    "-//mybatis.org//DTD Mapper 3.0//EN"
    "http://mybatis.org/dtd/mybatis-3-mapper.dtd">

<mapper namespace="User">
    <select id="selectUser" parameterType="int" resultType="UserInfo">
    <![CDATA[
        select * from user_info where id = #{id}
    ]]>
    </select>
</mapper>

 

（4）将UserInfo.xml引用到mybatis.cfg.xml文件中，mybatis.cfg.xml文件更新后的内容如下：

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

<!DOCTYPE configuration PUBLIC 
    "-//mybatis.org//DTD Config 3.0//EN"
    "http://mybatis.org/dtd/mybatis-3-config.dtd">

<configuration>
    <typeAliases>
        <typeAlias alias="UserInfo" type="com.user.UserInfo" />
    </typeAliases>
    
    <environments default="development">
        <environment id="development">
            <transactionManager type="JDBC" />
            <dataSource type="POOLED">
              <property name="driver" value="oracle.jdbc.OracleDriver" />
              <property name="url" value="jdbc:oracle:thin:@localhost:1521:ORACLEDB" />
              <property name="username" value="oracle" />
              <property name="password" value="oracle" />
            </dataSource>
        </environment>
    </environments>
   
    <mappers>
        <mapper resource="com/user/sqlmap/UserInfo.xml" />
    </mappers>
</configuration>

 

（5）新建一个测试Java类UserInfoTest.java，该类的具体内容如下：

package com.user;

import java.io.IOException;
import java.io.Reader;

import org.apache.ibatis.io.Resources;
import org.apache.ibatis.session.SqlSession;
import org.apache.ibatis.session.SqlSessionFactory;
import org.apache.ibatis.session.SqlSessionFactoryBuilder;



public class UserInfoTest {

	/**
	 * @param args
	 * @throws IOException 
	 */
	public static void main(String[] args) throws IOException {
		String resource = "mybatis.cfg.xml";
        Reader reader = Resources.getResourceAsReader(resource);
        SqlSessionFactory ssf = new SqlSessionFactoryBuilder().build(reader);
        
        SqlSession session = ssf.openSession();
        
        try {
        	UserInfo user = (UserInfo) session.selectOne("User.selectUser", "1");
            System.out.println(user);
        } catch (Exception e) {
            e.printStackTrace();
        } finally {
            session.close();
        }
	}

}

 

（6）右键UserInfoTest 类，选择Run As Application，运行MyBaits操作数据库。

 

log4j:WARN No appenders could be found for logger (org.apache.ibatis.logging.LogFactory).
log4j:WARN Please initialize the log4j system properly.
log4j:WARN See http://logging.apache.org/log4j/1.2/faq.html#noconfig for more info.
2012-02-11 21:44:01,750 DEBUG [java.sql.PreparedStatement] -==>  Executing: select * from user_info where id = ? 
2012-02-11 21:44:01,781 DEBUG [java.sql.PreparedStatement] -==> Parameters: 1(String)
ID: 1, Name: 张三