4、使用注解完成全套增删改查

1.创建javaweb项目MyBaits_Part4_@Base

2.在项目的WebRoot下的WEB-INF下的lib包下添加如下jar文件

mybatis-3.2.3.jar

ojdbc14.jar

3.在src下的配置链接数据库的属性文件jdbc.properties

driver=oracle.jdbc.driver.OracleDriver
url=jdbc:oracle:thin:@127.0.0.1:1521:orcl
username=holly
password=sys

4.在src下创建mybatisConfig.xml主配置文件

<?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>

  <!-- 1.引用jdbc链接数据库的属性文件 -->
  <properties resource="jdbc.properties"/>
  
  <!-- 2.类路径的别名 -->
  <typeAliases>
    <typeAlias type="com.entity.Teacher" alias="Teacher"/>
  </typeAliases>
  
  <!-- 3.事务和数据源的配置 -->
  <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>
  <!-- 4.注册映射文件 -->
  <mappers>
  <!-- 有映射文件时resource属性=映射文件的路径 -->
  <!-- 使用注解没有映射文件时class属性=映射文件的路径 -->
  <!-- 如果低版本dtd，使用注解，这里还是配置resouce=映射xml文件，
  但是映射文件的mapper节点上只写一个namespace=映射接口的全路径
  <mapper resource="com/mapper/TeacherMapper.xml"/>
   -->
    <!-- 如果高版本dtd，使用注解，这里如下配置，不需要写映射的xml文件"/>
   -->
  <mapper class="com.mapper.TeacherMapper"/>
   
  </mappers>
  
</configuration>

5.在src下的com.entity包下创建Teacher.java

package com.entity;

public class Teacher {
    private int tid;
    private String tname;
    
    public Teacher() {
    }
    public Teacher(int tid, String tname) {
        this.tid = tid;
        this.tname = tname;
    }
    public int getTid() {
        return tid;
    }
    public void setTid(int tid) {
        this.tid = tid;
    }
    public String getTname() {
        return tname;
    }
    public void setTname(String tname) {
        this.tname = tname;
    }
    @Override
    public String toString() {
        return "Teacher [tid=" + tid + ", tname=" + tname + "]";
    }
    

}

6.在src下的com.util包下创建MybatisUtil.java

package com.util;

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 MyBaitsUtil {
    private static SqlSessionFactory sqlSessionFactory;
    
    static{
        try {
            Reader reader=Resources.getResourceAsReader("configuration.xml");
            sqlSessionFactory=new SqlSessionFactoryBuilder().build(reader); 
        } catch (IOException e) {
            e.printStackTrace();
        }
        
    }
    /**
     * 
     * @param isCommit true表示执行完操作提交事务，false表示执行完不自动提交事务
     * @return
     */
    public static SqlSession getSqlSession(boolean isCommit){
        return sqlSessionFactory.openSession(isCommit);
    }

}

7.在src下的com.mapper包下创建TeacherMapper.java

package com.mapper;

import java.util.List;

import org.apache.ibatis.annotations.Delete;
import org.apache.ibatis.annotations.Insert;
import org.apache.ibatis.annotations.Select;
import org.apache.ibatis.annotations.Update;

import com.entity.Teacher;

public interface TeacherMapper {
    @Insert("insert into teacher values(seq_teacher.nextval,#{tname}")
    int saveTeacher(Teacher teacher);
    
    @Select("select * from teacher")
    List<Teacher> findAll();
    
    @Select("select * from teacher where tid=#{tid}")
    Teacher findById(int id);
    
    @Update("update teacher set tname=#{tname} where tid=#{tid}")
    int updateTeacher(Teacher teacher);
    
    @Delete("delete from teacher where tid=#{tid}")
    int deleteTeacher(int id);
}

8.在src下的com.test包下创建Test.java

package com.test;

import java.util.List;

import org.apache.ibatis.session.SqlSession;

import com.entity.Teacher;
import com.mapper.TeacherMapper;
import com.util.MyBaitsUtil;

public class Test {

    /**
     * @param args
     */
    public static void main(String[] args) {
        SqlSession sqlSession=MyBaitsUtil.getSqlSession(false);
        
        TeacherMapper mapper=sqlSession.getMapper(TeacherMapper.class);
        List<Teacher> list=mapper.findAll();
        for (Teacher teacher : list) {
            System.out.println(teacher);
        }
        sqlSession.close();
    
    }

}