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