Mybatis连接Oracle实现增删改查实践

1. 首先要在项目中增加Mybatis和Oracle的Jar文件

这里我使用的版本为ojdbc7

Mybatis版本为：3.2.4

2. 在Oracle中创建User表

create table T_USERS
(
  ID      NUMBER not null,
  NAME    VARCHAR2(30),
  SEX     VARCHAR2(3),
  BIRS    DATE,
  MESSAGE CLOB
);
create sequence SEQ_T_USERS_ID
minvalue 1
maxvalue 99999999
start with 1
increment by 1
cache 20;

　　

3.创建User类

public class User {
	 private String name;
	    private String sex;
	    private Integer id;
	    private Date birs;
	    private String message;  

	    public String getMessage() {
	        return message;
	    }  

	    public void setMessage(String pMessage) {
	        this.message = pMessage;
	    }  

	    public Date getBirs() {
	        return birs;
	    }  

	    public void setBirs(Date pbirs) {
	        this.birs = pbirs;
	    }  

	    public String getName() {
	        return name;
	    }  

	    public void setName(String name) {
	        this.name = name;
	    }  

	    public String getSex() {
	        return sex;
	    }  

	    public void setSex(String psex) {
	        this.sex = psex;
	    }  

	    public Integer getId() {
	        return id;
	    }  

	    public void setID(Integer pid) {
	        this.id = pid;
	    }  

	    public User() {
	    }

		@Override
		public String toString() {
			return "User [name=" + name + ", sex=" + sex + ", id=" + id + ", birs=" + birs + ", message=" + message
					+ "]";
		}  

}

　　

4. 创建UsersMapper接口

public interface UsersMapper {
	  public void add(User t);  

	    public void update(User t);  

	    public void updateBySelective(User t);  

	    public void delete(Object id);  

	    public User queryById(Object id);  

	    public List<User> queryBySelective(User t);  

	    public int queryByCount(User t);  

	    public List<User> queryByList(User t);
}

　　

5. 创建OracleClobTypeHandler.java

import java.sql.CallableStatement;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;

import org.apache.ibatis.type.JdbcType;
import org.apache.ibatis.type.TypeHandler;

import oracle.sql.CLOB;

public class OracleClobTypeHandler  implements TypeHandler<Object> {

	 public Object valueOf(String param) {
	        return null;
	    }  

	    public Object getResult(ResultSet arg0, String arg1) throws SQLException {
	        CLOB clob = (CLOB) arg0.getClob(arg1);
	        return (clob == null || clob.length() == 0) ? null : clob.getSubString((long) 1, (int) clob.length());
	    }  

	    public Object getResult(ResultSet arg0, int arg1) throws SQLException {
	        return null;
	    }  

	    public Object getResult(CallableStatement arg0, int arg1) throws SQLException {
	        return null;
	    }  

	    public void setParameter(PreparedStatement arg0, int arg1, Object arg2, JdbcType arg3) throws SQLException {
	        CLOB clob = CLOB.empty_lob();
	        clob.setString(1, (String) arg2);
	        arg0.setClob(arg1, clob);
	    }  

}

　　

6. 创建配置文件

configuration.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>

    <typeAliases>
        <!--给实体类起一个别名 user 不过建议不要起别名，容易搞混-->
        <typeAlias type="com.example.oracle.User" alias="User" />
    </typeAliases>
    <!--数据源配置  这块用 Oracle数据库 -->
    <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:@127.0.0.1:1521:orcl" />
                <property name="username" value="system" />
                <property name="password" value="123456" />
            </dataSource>
        </environment>
    </environments>
    <mappers>
        <!--UsersMapper.xml装载进来  同等于把“dao”的实现装载进来 -->
        <mapper resource="UsersMapper.xml" />
    </mappers>
</configuration>

　　

UsersMapper.xml文件

<?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">
  <!--这块等于dao接口的实现  namespace必须和接口的类路径一样-->
<mapper namespace="com.example.mapper.UsersMapper" >  

    <!-- Result Map-->
    <resultMap type="com.example.oracle.User" id="BaseResultMap">
        <result property="id" column="id" />
        <result property="name" column="name" />
        <result property="sex" column="sex" />
        <result property="birs" column="birs" jdbcType="TIMESTAMP"/>
        <result property="message" column="message" jdbcType="CLOB" javaType = "java.lang.String"  typeHandler ="com.example.oracle.OracleClobTypeHandler"/>
    </resultMap>  

    <!-- 表名-->
    <sql id="Tabel_Name">
        t_users
    </sql>  

    <!-- 表中所有列 -->
    <sql id="Base_Column_List" >
        id,name,sex,birs,message
    </sql>  

    <!-- 查询条件 -->
    <sql id="Example_Where_Clause">
        where 1=1
        <trim suffixOverrides=",">
            <if test="id != null">
                and id = #{id}
            </if>
            <if test="name != null and name != ''">
                and name like concat(concat('%', '${name}'), '%')
            </if>
            <if test="sex != null and sex != ''">
                and sex like concat(concat('%', '${sex}'), '%')
            </if>
            <if test="birs != null">
                and birs = #{birs}
            </if>
            <if test="message != null">
                and message = #{message}
            </if>
        </trim>
    </sql>  

    <!-- 下面的id都和接口UsersMapper中的方法名一样-->  

    <!-- 1.新增记录 -->
    <insert id="add" parameterType="Object" >
         <selectKey resultType="int" order="BEFORE" keyProperty="id">
            select seq_t_users_id.nextval as id from dual
        </selectKey>
        insert into t_users(id,name,sex,birs,message) values(#{id},#{name},#{sex},#{birs},#{message,jdbcType=CLOB})
    </insert>  

    <!-- 2.根据id修改记录-->
    <update id="update" parameterType="Object" >
        update t_users set name=#{name},sex=#{sex},birs=#{birs},message=#{message} where id=#{id}
    </update>  

    <!-- 3.只修改不为空的字段 -->
    <update id="updateBySelective" parameterType="Object" >
        update t_users set
        <trim  suffixOverrides="," >
            <if test="name != null  and name != '' ">
                name=#{name},
            </if>
            <if test="sex != null  and sex != '' ">
                sex=#{sex},
            </if>
            <if test="birs != null  ">
                birs=#{birs},
            </if>
            <if test="message != null  and message != '' ">
                message=#{message},
            </if>
        </trim> where id=#{id}
    </update>  

    <!-- 4.根据id进行删除 -->
    <delete id="delete" parameterType="Object">
        delete from t_users where id = #{id}
    </delete>  

    <!-- 5.根据id查询 -->
    <select id="queryById" resultMap="BaseResultMap" parameterType="Object">
        select
        <include refid="Base_Column_List" />
        from t_users where id = #{id}
    </select>  

    <!-- 6.查询列表，只查询不为空的字段 -->
    <select id="queryBySelective" resultMap="BaseResultMap" parameterType="Object">
        select
        <include refid="Base_Column_List" />
        from t_users
        <include refid="Example_Where_Clause" />
    </select>  

    <!-- 7.列表总数 -->
    <select id="queryByCount" resultType="java.lang.Integer" parameterType="Object">
        select count(1) from t_users
        <include refid="Example_Where_Clause" />
    </select>  

    <!-- 8.查询列表 -->
    <select id="queryByList" resultMap="BaseResultMap" parameterType="Object">
        select
        <include refid="Base_Column_List" />
        from t_users
        <include refid="Example_Where_Clause"/>
    </select>
</mapper>

　　两个xml文件路径为：

7 .在main方法中测试

public class OracleMain {

	private static SqlSessionFactory getSessionFactory(){
		SqlSessionFactory sessionFactory = null;
		String resource = "configuration.xml";
		try{
			sessionFactory = new SqlSessionFactoryBuilder()
					.build(Resources.getResourceAsReader(resource));
		}catch(IOException e){
			e.printStackTrace();
		}
		return sessionFactory;
	}

	public static void main(String[] args) {
		 SqlSession sqlSession = getSessionFactory().openSession();
		 UsersMapper dao = sqlSession.getMapper(UsersMapper.class);

	     //删除表中所有信息
	    User nullBean = new User();
	    List<User> delList = dao.queryByList(nullBean);
	    for(User user: delList){
    		dao.delete(user.getId());
    	}

	    DateFormat dd=new SimpleDateFormat("yyyy-MM-dd");
        Date date=null;
        try {
            date = dd.parse("1985-01-01");
        } catch (ParseException e) {
            e.printStackTrace();
        }  

	    //新增用戶
		User bean = new User();
		bean.setName("张三");
		bean.setSex("男");
		bean.setBirs(date);
		bean.setMessage("您好，我是张三");
		dao.add(bean);

		bean = new User();
		bean.setName("李四");
		bean.setSex("男");
		bean.setBirs(date);
		bean.setMessage("您好，我是李四");
		dao.add(bean);

		printUserInfo(dao);

		//查詢并更新
		bean = new User();
		bean.setName("李四");
		List<User> list = dao.queryByList(bean);
		for(User user : list){
			user.setName("王五");
			user.setSex("女");
			dao.update(user);
		}
		System.out.println("---------更新--------------");
		printUserInfo(dao);

		int num = dao.queryByCount(nullBean);
		System.out.println("num="+ num);

		sqlSession.commit();  

	}

	private static void printUserInfo(UsersMapper dao) {
		User nullBean = new User();
		List<User> list = dao.queryByList(nullBean);
		for(User user : list){
			System.out.println(user.getName() + " " + user.getMessage());
		}
	}
}