mybatis：@Intercepts小例子（一）

這只是一個純碎的mybatis的只針對@Intercepts應用的小列子，沒有和spring做集成。

1.工作目錄

2.數據庫mysql，建立一個數據庫表、實體對象User、UserMapper.java、UserMapper.xml省略。

使用mybatis自動代碼生成工具生成：mybatis-generator-core-1.3.2。（此處略）

3.攔截器MyInterceptor.java

package com.tiantian.mybatis.interceptor;

import java.sql.Connection;
import java.util.Properties;
import org.apache.ibatis.executor.Executor;
import org.apache.ibatis.executor.statement.StatementHandler;
import org.apache.ibatis.mapping.MappedStatement;
import org.apache.ibatis.plugin.Interceptor;
import org.apache.ibatis.plugin.Intercepts;
import org.apache.ibatis.plugin.Invocation;
import org.apache.ibatis.plugin.Plugin;
import org.apache.ibatis.plugin.Signature;
import org.apache.ibatis.session.ResultHandler;
import org.apache.ibatis.session.RowBounds;
@Intercepts( {
    @Signature(method = "query", type = Executor.class, args = {
           MappedStatement.class, Object.class, RowBounds.class,
           ResultHandler.class }),
    @Signature(method = "prepare", type = StatementHandler.class, args = { Connection.class }) })
public class MyInterceptor implements Interceptor {
    @Override
    public Object intercept(Invocation invocation) throws Throwable {
        Object result = invocation.proceed();
        System.out.println("Invocation.proceed()");
        return result;
    }

    @Override
    public Object plugin(Object target) {
        // TODO Auto-generated method stub
        return Plugin.wrap(target, this);
    }

    @Override
    public void setProperties(Properties properties) {
        String prop1 = properties.getProperty("prop1");
        String prop2 = properties.getProperty("prop2");
        System.out.println(prop1 + "------" + prop2);
    }
}

4.配置文件mybatis-config.xml

<?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>
    <properties resource="jdbc.properties"></properties>
    <typeAliases>
       <package name="com.tiantian.mybatis.model"/>
    </typeAliases>
    <plugins>
       <plugin interceptor="com.tiantian.mybatis.interceptor.MyInterceptor">
           <property name="prop1" value="prop1"/>
           <property name="prop2" value="prop2"/>
       </plugin>
    </plugins>
    <environments default="development">
       <environment id="development">
           <transactionManager type="JDBC" />
           <dataSource type="POOLED">
              <property name="driver" value="${driver}" />
              <property name="url" value="${url}" />
              <property name="username" value="${username}" />
              <property name="password" value="${password}" />
           </dataSource>
       </environment>
    </environments>
    <mappers>
       <mapper resource="com/tiantian/mybatis/mapper/UserMapper.xml"/>
    </mappers>
</configuration>

5.配置文件jdbc.properties

driver=com.mysql.jdbc.Driver
url=jdbc:mysql://localhost:3306/database_yxl
username=root
password=123456
#定義初始連接數
initialSize=0
#定義最大連接數
maxActive=20
#定義最大空閑
maxIdle=20
#定義最小空閑
minIdle=1
#定義最長等待時間
maxWait=60000

6.測試文件TestMyBatis.java

package com.tiantian.mybatis.service;

import org.apache.ibatis.session.SqlSession;
import com.tiantian.base.MyBatisUtil;
import com.tiantian.mybatis.domain.User;

public class TestMyBatis {
    public static void main(String[] args) {
        SqlSession session = MyBatisUtil.getSqlSession();
        /**
         * 映射sql的標識字符串，
         * com.tiantian.mybatis.mapper.userMapper是userMapper.xml文件中mapper標簽的namespace屬性的值，
         * selectByPrimaryKey是select標簽的id屬性值，通過select標簽的id屬性值就可以找到要執行的SQL
         */
        String statement = "com.tiantian.mybatis.mapper.UserMapper.selectByPrimaryKey";//映射sql的標識字符串
        //執行查詢返回一個唯一user對象的sql
        User user = session.selectOne(statement, 1);
        System.out.println(user);
    }
}

輸出結果：

prop1------prop2
Invocation.proceed()
Invocation.proceed()
[id:1;username:測試;password:sfasgfaf]

7.工具類MyBatisUtil.java

package com.tiantian.base;

import java.io.InputStream;
import org.apache.ibatis.session.SqlSession;
import org.apache.ibatis.session.SqlSessionFactory;
import org.apache.ibatis.session.SqlSessionFactoryBuilder;

public class MyBatisUtil {
    public static SqlSessionFactory getSqlSessionFactory() {
        String resource = "mybatis-config.xml";
        // 使用類加載器加載mybatis的配置文件（它也加載關聯的映射文件）
        InputStream is = MyBatisUtil.class.getClassLoader().getResourceAsStream(resource);
        // 構建sqlSession的工廠
        SqlSessionFactory sessionFactory = new SqlSessionFactoryBuilder().build(is);
        return sessionFactory;
    }

    public static SqlSession getSqlSession() {
        return getSqlSessionFactory().openSession();
    }

    public static SqlSession getSqlSession(boolean isAutoCommit) {
        return getSqlSessionFactory().openSession(isAutoCommit);
    }
}

 

參考文章

http://www.tuicool.com/articles/7bYjUn

http://www.cnblogs.com/xdp-gacl/p/4262895.html

http://www.mybatis.org/mybatis-3/zh/index.html