SSM15.4【Mybatis：Mybatis的多表操作总结】

 

 

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<?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">

<!--The content of element type "configuration" must match
"(properties?,settings?,typeAliases?,typeHandlers?,objectFactory?,
objectWrapperFactory?,reflectorFactory?,plugins?,environments?,databaseIdProvider?,mappers?)".-->

<configuration>

    <!--加载外部properties文件-->
    <properties resource="jdbc.properties"></properties>

    <!--自定义别名-->
    <typeAliases>
        <typeAlias type="com.haifei.domain.User" alias="user" />
        <typeAlias type="com.haifei.domain.Order" alias="order"/>
        <typeAlias type="com.haifei.domain.Role" alias="role"/>
    </typeAliases>

    <!--注册类型处理器-->
    <typeHandlers>
        <typeHandler handler="com.haifei.handler.DateTypeHandler"/>
    </typeHandlers>

    <environments default="development">
        <!--配置数据源环境-->
        <environment id="development">
            <transactionManager type="JDBC"></transactionManager>
            <dataSource type="POOLED">
                <property name="driver" value="${jdbc.driver}"/>
                <property name="url" value="${jdbc.url}"/>
                <property name="username" value="${jdbc.username}"/>
                <property name="password" value="${jdbc.password}"/>
            </dataSource>
        </environment>
    </environments>

    <!--加载映射文件-->
    <mappers>
        <mapper resource="com/haifei/mapper/UserMapper.xml"/>
        <mapper resource="com/haifei/mapper/OrderMapper.xml"/>
    </mappers>

</configuration>

package com.haifei.handler;

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

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

public class DateTypeHandler extends BaseTypeHandler<Date> {

    /**
     * 将java数据类型 转换为 数据库所需的数据类型
     * @param preparedStatement
     * @param i
     * @param date
     * @param jdbcType
     * @throws SQLException
     */
    @Override
    public void setNonNullParameter(PreparedStatement preparedStatement, int i, Date date, JdbcType jdbcType) throws SQLException {
        long time = date.getTime();
        preparedStatement.setLong(i, time);
    }

    /**
     * 将数据库中的数据类型 转换为 所需的java数据类型
     * @param resultSet  查询出的结果集
     * @param s  要转换的字段名称
     * @return
     * @throws SQLException
     */
    @Override
    public Date getNullableResult(ResultSet resultSet, String s) throws SQLException {
        //获取结果集中需要的数据类型（long）转换为Date类型，并返回
        long aLong = resultSet.getLong(s);
        Date date = new Date(aLong);
        return date;
    }

    /**
     * 将数据库中的数据类型 转换为 所需的java数据类型
     * @param resultSet
     * @param i
     * @return
     * @throws SQLException
     */
    @Override
    public Date getNullableResult(ResultSet resultSet, int i) throws SQLException {
        long aLong = resultSet.getLong(i);
        Date date = new Date(aLong);
        return date;
    }

    /**
     * 将数据库中的数据类型 转换为 所需的java数据类型
     * @param callableStatement
     * @param i
     * @return
     * @throws SQLException
     */
    @Override
    public Date getNullableResult(CallableStatement callableStatement, int i) throws SQLException {
        long aLong = callableStatement.getLong(i);
        Date date = new Date(aLong);
        return date;
    }
}

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