Mybatis实现数据的增删改查

Mybatis实现数据的增删改查

1、项目结构(使用maven创建项目)

2、App.java

package com.GetcharZp.MyBatisStudy;

import java.io.IOException;
import java.io.InputStream;
import java.util.List;

import org.apache.ibatis.io.Resources;
import org.apache.ibatis.session.SqlSession;
import org.apache.ibatis.session.SqlSessionFactory;
import org.apache.ibatis.session.SqlSessionFactoryBuilder;

import com.GetcharZp.MyBatisStudy.dao.TradeDao;
import com.GetcharZp.MyBatisStudy.model.Trade;

/**
 * Hello world!
 *
 */
public class App 
{
    public static void main( String[] args )
    {
        InputStream config = null;
        try {
            config = Resources.getResourceAsStream("mybatis-config.xml");
            SqlSessionFactory factory = new SqlSessionFactoryBuilder().build(config);
            SqlSession session = factory.openSession();            
            TradeDao tradeDao = session.getMapper(TradeDao.class);
            
            
            
            /*删除*/
            tradeDao.deleteTrade(3);
            session.commit(); // 删除要提交
            
            /*查询*/
            List<Trade> tradeList = tradeDao.selectTrade();
            System.out.println(tradeList);
            System.out.println(tradeList.size());
            Trade trade = tradeDao.findById(2);
            System.out.println(trade); // 日志里面有输出，但结果没有
            
            /*插入*/
            Trade InsertTrade = new Trade();
            InsertTrade.setTradeId(4);
            InsertTrade.setTradeName("毛笔");
            InsertTrade.setTradePrice(5.6);
            tradeDao.insertTrade(InsertTrade);
            session.commit();
            
            /*更新*/
            Trade updateTrade1 = new Trade();
            updateTrade1.setTradeName("watch");
            updateTrade1.setTradePrice(520.1314);
            tradeDao.updateTrade(3);
            session.commit();
            
            session.close();
            
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            if (config != null)
                try {
                    config.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
        }
    }
}

3、TradeDao

package com.GetcharZp.MyBatisStudy.dao;

import java.util.List;

import com.GetcharZp.MyBatisStudy.model.Trade;

public interface TradeDao { // interface 接口

    public List<Trade> selectTrade();
    public void deleteTrade(int tradeId);
    public void updateTrade(int tradeId);
    public void insertTrade(Trade newTrade);
    public Trade findById(int tradeId);
}

4、Trade

package com.GetcharZp.MyBatisStudy.model;

public class Trade {

    private Integer tradeId;
    private String tradeName;
    private Double tradePrice;
    public Integer getTradeId() {
        return tradeId;
    }
    public void setTradeId(Integer tradeId) {
        this.tradeId = tradeId;
    }
    public String getTradeName() {
        return tradeName;
    }
    public void setTradeName(String tradeName) {
        this.tradeName = tradeName;
    }
    public Double getTradePrice() {
        return tradePrice;
    }
    public void setTradePrice(Double tradePrice) {
        this.tradePrice = tradePrice;
    }
    @Override
    public String toString() {
        return "Trade [tradeId=" + tradeId + ", tradeName=" + tradeName + ", tradePrice=" + tradePrice + "]";
    }
}

5、TradeMapper

<?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">
        
        
<mapper namespace="com.GetcharZp.MyBatisStudy.dao.TradeDao">
    <select id="selectTrade" resultType="com.GetcharZp.MyBatisStudy.model.Trade">
        select * from trade
    </select>
    <select id="findById" resultType="com.GetcharZp.MyBatisStudy.model.Trade">
        select * from trade where trade_id=#{tradeId}
    </select>
    <delete id="deleteTrade">
        delete from trade where trade_id = #{tradeId}
    </delete>
    <insert id="insertTrade">
        insert into trade (trade_id, trade_name, trade_price)
        values(#{tradeId}, #{tradeName}, #{tradePrice})
    </insert>
    <update id="updateTrade">
        update trade set 
            trade_name = #{tradeName},
            trade_price = #{tradePrice}
        where
            trade_id = #{tradeId}
    </update>
</mapper>

6、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>
    <settings>
        <!-- <setting name="logImpl" value="STDOUT_LOGGING" /> -->
        <setting name="logImpl" value="STDOUT_LOGGING"/>
    </settings>
    <typeAliases>
        <package name="com.GetcharZp.MyBatisStudy.model"/>
    </typeAliases>
    <environments default="dev">
        <environment id="dev">
            <transactionManager type="JDBC"></transactionManager>
            <dataSource type="POOLED">
                <property name="driver" value="com.mysql.jdbc.Driver"/>
                <property name="url" value="jdbc:mysql://localhost:3306/suse"/>
                <property name="username" value="root"/>
                <property name="password" value="1234"/>
            </dataSource>
        </environment>
    </environments>
    <mappers>
        <mapper resource="mappers/TradeMapper.xml"/>
    </mappers>
</configuration>

7、pom.xml:

<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
  <modelVersion>4.0.0</modelVersion>

  <groupId>com.GetcharZp.MyBatisStudy</groupId>
  <artifactId>Mybatis</artifactId>
  <version>1.0-SNAPSHOT</version>
  <packaging>jar</packaging>

  <name>Mybatis</name>
  <url>http://maven.apache.org</url>

  <properties>
    <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
  </properties>

  <dependencies>
    <dependency>
      <groupId>junit</groupId>
      <artifactId>junit</artifactId>
      <version>3.8.1</version>
      <scope>test</scope>
    </dependency>
    <dependency>
      <groupId>org.mybatis</groupId>
      <artifactId>mybatis</artifactId>
      <version>3.4.1</version>
    </dependency>

    <dependency>
      <groupId>mysql</groupId>
      <artifactId>mysql-connector-java</artifactId>
      <version>5.1.38</version>
    </dependency>
  </dependencies>
</project>