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Mybatis注解学习--xxxMapper is not known to the MapperRegistry

2012-11-07 00:09  Rollen Holt  阅读(41789)  评论(0编辑  收藏  举报

今天晚上在学习Mybatis注解的时候,总是遇到错误Type interface com.souvi.ibatis.xxxMapper is  not known to the MapperRegistry,在网上搜索相关的解决方案时,得到的答案都不怎么详细,但知道了Mybatis注解一定要注册自己写的接口类,不然就会老报开头提到的这个错误。

下面举个例子:先看看项目的简单部署吧,如图:

先看核心文件,UserTest.java

package com.rollen;

import java.io.*;

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 UserTest {
	public static void main(String[] args) {

		String resource = "com/rollen/configure.xml";

		Reader reader = null;
		try {
			reader = Resources.getResourceAsReader(resource);
		} catch (IOException e) {
			e.printStackTrace();
		}

		SqlSessionFactory factory = new SqlSessionFactoryBuilder()
				.build(reader);
		factory.getConfiguration().addMapper(UserInfoMapper.class);
		SqlSession sqlSession = factory.openSession();
		try {
			UserInfoMapper userInfoMapper = sqlSession
					.getMapper(UserInfoMapper.class);
			User user = userInfoMapper.getUser(10);
			System.out.println(user);
		} finally {
			sqlSession.close();
		}
	}
}

  主要要注意的是比如要注册,也就是这行代码:

factory.getConfiguration().addMapper(UserInfoMapper.class);

  UserInfoMapper.java代码如下:

package com.rollen;

import org.apache.ibatis.annotations.Select;

public interface UserInfoMapper {
	@Select("select * from user_tb where age= #{age}")
	public User getUser(int age);
}

  user.java 代码如下:

package com.rollen;

public class User {
	private String name;
	private int age;
	/**
	 * @return the name
	 */
	public String getName() {
		return name;
	}
	/**
	 * @param name the name to set
	 */
	public void setName(String name) {
		this.name = name;
	}
	/**
	 * @return the age
	 */
	public int getAge() {
		return age;
	}
	/**
	 * @param age the age to set
	 */
	public void setAge(int age) {
		this.age = age;
	}
	/* (non-Javadoc)
	 * @see java.lang.Object#toString()
	 */
	@Override
	public String toString() {
		// TODO Auto-generated method stub
		return "name: "+name+"age: "+age;
	}
	
	
}

  最后的configure.xml文件代码为:

<?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="User" type="com.rollen.User" />
	</typeAliases>
	<environments default="development">
		<environment id="development">
			<transactionManager type="JDBC" />
			<dataSource type="POOLED">
				<property name="driver" value="com.mysql.jdbc.Driver" />
				<property name="url" value="jdbc:mysql://localhost:3306/user_db" />
				<property name="username" value="root" />
				<property name="password" value="root" />
			</dataSource>
		</environment>
	</environments>
</configuration>  

  参考文章:http://www.laokboke.net/2012/09/25/mybatis-annotation/