java 单独使用 mybaties 连接数据库(非web)

1.项目文件数据结构,项目由maven构建

pom. 需要引入相关jar包

<dependency>
            <groupId>org.mybatis</groupId>
            <artifactId>mybatis</artifactId>
            <version>3.2.3</version>
        </dependency>
        <!-- https://mvnrepository.com/artifact/mysql/mysql-connector-java -->
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>8.0.13</version>
        </dependency>

source文件夹下为mybaities,数据库配置文件

mysql.properties  常用的就下面的几种

jdbc.driver=com.mysql.cj.jdbc.Driver
jdbc.url=jdbc\\:mysql\\://localhost\\:3306/anti?useUnicode\\=true&characterEncoding\\=utf8
jdbc.username=root
jdbc.password=root
jdbc.maxActive=10
jdbc.minIdle=5
jdbc.maxWait=50000

mybaties-config.   下面只是一个简单的配置，注意相关配置一定要符合项目文件夹结构

<?  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>
    <!-- 引入外部配置文件 -->
    <properties resource=\"mysql.properties\"></properties>
     <!-- 为JAVA Bean起类别名 -->
    <typeAliases >
         <!-- 别名方式1，一个一个的配置 type中放置的是类的全路径，alias中放置的是类别名
         <typeAliase type=\"com.cy.mybatis.beans.UserBean\" alias=\"UserBean\"/>-->
         <!-- 别名方式2，自动扫描，将JAVA类的类名作为类的类别名 -->
         <package name=\"com.AntiUav.Gis.Dao\"/>
    </typeAliases>
   
     <!-- 配置mybatis运行环境 -->
       <environments default=\"cybatis\">
         <environment id=\"cybatis\">
             <!-- type=\"JDBC\" 代表使用JDBC的提交和回滚来管理事务 -->
             <transactionManager type=\"JDBC\" />
             <!-- mybatis提供了3种数据源类型，分别是：POOLED,UNPOOLED,JNDI -->
             <!-- POOLED 表示支持JDBC数据源连接池 -->
             <!-- UNPOOLED 表示不支持数据源连接池 -->
             <!-- JNDI 表示支持外部数据源连接池 -->
             <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> 
     <mappers>
         <!-- 告知映射文件方式1，一个一个的配置
         <mapper resource=\"com/cy/mybatis/mapper/UserMapper. \"/>-->
         <!-- 告知映射文件方式2，自动扫描包内的Mapper接口与配置文件 -->
         <package name=\"com.AntiUav.Gis.Dao.Mapper\"/>
     </mappers>
</configuration>

Dao文件下主要做与数据交互的逻辑。

D e文件夹是做数据库连接

Mapper文件夹是具体查询的sql和mapper映射

Entity是数据库表对应的实体类，model

DataService就是相对web架构中的sevice层，为control层服务的。

MysqlTool,利用mybaties，这里采用单例模式，一个单体项目只需和数据库建立一次连接。（也可以用静态代码块实现，相对优劣，可以去查查单例和静态方法的区别）

package com.AntiUav.Gis.Dao.D ;

import java.io.Reader;
import java.sql.Connection;

import javax.management.RuntimeErrorException;

import org.apache.ibatis.io.Resources;
import org.apache.ibatis.session.Configuration;
import org.apache.ibatis.session.ExecutorType;
import org.apache.ibatis.session.SqlSession;
import org.apache.ibatis.session.SqlSessionFactory;
import org.apache.ibatis.session.SqlSessionFactoryBuilder;
import org.apache.ibatis.session.TransactionIsolationLevel;
/**
 * 多线程的单例模式，使用双重校验机制
 */
public class MysqlTool {
	public volatile static SqlSessionFactory sessionFactory;
	
	public static SqlSession getInstance() {
        if (sessionFactory == null)
            synchronized (MysqlTool.class) {
                if (sessionFactory == null) {
                	try {
            			Reader reader = Resources.getResourceAsReader(\"mybatis-config. \");
            			sessionFactory = new SqlSessionFactoryBuilder().build(reader);
            		}catch (Exception e) {
            			System.out.println(\"数据库连接错误！\");
            			e.printStackTrace();
            			//throw  new RuntimeErrorException( null, \"连接mysql数据库错误\");
            		}
                }
            }
        return sessionFactory.openSession();
    }
//	static {
//		try {
//			Reader reader = Resources.getResourceAsReader(\"mybatis-config. \");
//			sessionFactory = new SqlSessionFactoryBuilder().build(reader);
//			
//		}catch (Exception e) {
//			System.out.println(\"数据库连接错误！\");
//			e.printStackTrace();
//			//throw  new RuntimeErrorException( null, \"连接mysql数据库错误\");
//		}
//	}
//	
//	public static SqlSession getSession() {
//		return sessionFactory.openSession();
//	}
}

DataSevice下的linePointService也是采用单例实现的，静态实现的被注释掉了。这样可以保证访问这张表也是单例的。不同业务不同实现，不一定非要单例。

package com.AntiUav.Gis.Dao.DataService;

import java.util.List;

import org.apache.ibatis.session.SqlSession;

import com.AntiUav.Gis.Dao.D .MysqlTool;
import com.AntiUav.Gis.Dao.Entity.LinePoint;
import com.AntiUav.Gis.Dao.Mapper.LinePointsMapper;


public class LinePointsService {
	private static SqlSession session ;
	private static LinePointsMapper mapper;
	private volatile static LinePointsService linePointsService;
	public LinePointsService()
	{
		session = MysqlTool.getInstance();
		mapper = session.getMapper(LinePointsMapper.class);
	}
	
	public static LinePointsService getInstance() {
        if (linePointsService == null)
            synchronized (LinePointsService.class) {
                if (linePointsService == null) {
                	linePointsService = new LinePointsService();
                }
            }
        return linePointsService;
    }
	
	public  List<LinePoint> getLine(int line) {
		try {
			List<LinePoint> pointsList = mapper.getLine(line);
			session.commit();
			return pointsList;
		} catch (Exception e) {
		e.printStackTrace();
			session.rollback();
		}
		return null;
	}
	
	public static void addLinePoint(LinePoint point) {
		try {
			mapper.addLinePoint(point);
			session.commit();
		} catch (Exception e) {
		e.printStackTrace();
			session.rollback();
		}
	}
	
	public void delLinePoint(int num) {
		try {
			mapper.delLinePoint(num);
			session.commit();
		} catch (Exception e) {
		e.printStackTrace();
			session.rollback();
		}
	}
	
	
	
//	static {
//		session = MysqlTool.getInstance();
//		mapper = session.getMapper(LinePointsMapper.class);
//	}
	
//	public static List<LinePoint> getLine(int line) {
//		try {
//			List<LinePoint> pointsList = mapper.getLine(line);
//			session.commit();
//			return pointsList;
//		} catch (Exception e) {
//		e.printStackTrace();
//			session.rollback();
//		}
//		return null;
//	}
//	
//	public static void addLinePoint(LinePoint point) {
//		try {
//			mapper.addLinePoint(point);
//			session.commit();
//		} catch (Exception e) {
//		e.printStackTrace();
//			session.rollback();
//		}
//	}
//	
//	public void delLinePoint(int num) {
//		try {
//			mapper.delLinePoint(num);
//			session.commit();
//		} catch (Exception e) {
//		e.printStackTrace();
//			session.rollback();
//		}
//	}
}

另外粘贴下相关的实体类，映射mapper,和sql吧

LinePoint

package com.AntiUav.Gis.Dao.Entity;

import java.io.Serializable;
import java.util.Date;

public class LinePoint implements Serializable{
   public int id;
   public String UUID ;
   public String courseId;
   public int head;
   public int flag;
   public int num;
   public int historyNum;
   public double pitch;
   public double tilt;
   public double distance;
   public double height;
   public double speed;
   public double direction;
   public Date time;
   public double lat;
   public double lng;
   public String getUUID() {
		return UUID;
	}
	public void setUUID(String uUID) {
		UUID = uUID;
	}
	public String getCourseId() {
		return courseId;
	}
	public void setCourseId(String courseId) {
		this.courseId = courseId;
	}
	public int getHead() {
		return head;
	}
	public void setHead(int head) {
		this.head = head;
	}
	public int getFlag() {
		return flag;
	}
	public void setFlag(int flag) {
		this.flag = flag;
	}
	public int getNum() {
		return num;
	}
	public void setNum(int num) {
		this.num = num;
	}
	public int getHistoryNum() {
		return historyNum;
	}
	public void setHistoryNum(int historyNum) {
		this.historyNum = historyNum;
	}
	public double getPitch() {
		return pitch;
	}
	public void setPitch(double pitch) {
		this.pitch = pitch;
	}
	public double getTilt() {
		return tilt;
	}
	public void setTilt(double tilt) {
		this.tilt = tilt;
	}
	public double getDistance() {
		return distance;
	}
	public void setDistance(double distance) {
		this.distance = distance;
	}
	public double getHeight() {
		return height;
	}
	public void setHeight(double height) {
		this.height = height;
	}
	public double getSpeed() {
		return speed;
	}
	public void setSpeed(double speed) {
		this.speed = speed;
	}
	public double getDirection() {
		return direction;
	}
	public void setDirection(double direction) {
		this.direction = direction;
	}
	public Date getTime() {
		return time;
	}
	public void setTime(Date time) {
		this.time = time;
	}
	public double getLat() {
		return lat;
	}
	public void setLat(double lat) {
		this.lat = lat;
	}
	public double getLng() {
		return lng;
	}
	public void setLng(double lng) {
		this.lng = lng;
	}
}

LinePointsMapper.

<!DOCTYPE mapper
        PUBLIC \"-//mybatis.org//DTD Mapper 3.0//EN\"
        \"http://mybatis.org/dtd/mybatis-3-mapper.dtd\">
<mapper namespace=\"com.AntiUav.Gis.Dao.Mapper.LinePointsMapper\">
	<!--目的:为dao接口方法提供sql语句配置 即针对dao接口中的方法编写我们的sql语句 -->
	<select id=\"getLine\" parameterType=\"int\"
		resultType=\"com.AntiUav.Gis.Dao.Entity.LinePoint\">
		select * from LinePoints where num = #{num}
	</select>

	<insert id=\"addLinePoint\"
		parameterType=\"com.AntiUav.Gis.Dao.Entity.LinePoint\">
		insert into LinePoints(UUID ,coursedID,head,flag,
        num,historyNum,pitch,tilt,distance,height,speed,
        direction,time,lat,lng) 
        values(#{point.UUID},#{point.coursedID},#{point.head},#{point.flag},
        #{point.num},#{point.historyNum},#{point.pitch},#{point.tilt},#{point.distance},
        #{point.height},#{point.speed},#{point.direction},#{point.time},#{point.lat},
        #{point.lng})
	</insert>
	<delete id=\"delLinePoint\" parameterType=\"int\">
		delete from LinePoints where num=#{num}
	</delete>

</mapper>

LinePointsMapper.java

package com.AntiUav.Gis.Dao.Mapper;

import java.util.List;

import com.AntiUav.Gis.Dao.Entity.LinePoint;

public interface LinePointsMapper {
	
	public List<LinePoint> getLine(int num) ;
	
	public void addLinePoint(LinePoint point) ;
	
	public void delLinePoint(int num);
}

然后就是测试是否可以使用了

package com.AntiUav.Gis.GisView;

import java.util.List;

import org.apache.ibatis.session.SqlSession;

import com.AntiUav.Gis.Dao.DataService.LinePointsService;
import com.AntiUav.Gis.Dao.Entity.LinePoint;


public class testMysql {
	public static void main(String[] args) {
		LinePointsService l = LinePointsService.getInstance();
		List<LinePoint> pointsList = l.getLine(1);
		for (LinePoint linePoint : pointsList) {
			System.out.println(linePoint.getLat()+\",\"+linePoint.getLng()+\",\"+linePoint.getTime());
		}
}