//先建立一個包名字為com.mchange.v2.log 必須為這個名
//寫個Emp實體類 用來暫時儲存使用者輸入的資料
package com.mchange.v2.log;
public class Emp {
    private int id;
    private String name;
    private int age;

    public Emp() {
    }

    public Emp(int id, String name, int age) {
        this.id = id;
        this.name = name;
        
 
this.age = age;
    }

    public int getId() {
        return id;
    }

    public void setId(int id) {
        this.id = id;
    }

    public String getName() {
        return name;
    }

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

    public int getAge() {
        return
 
 age;
    }

    public void setAge(int age) {
        this.age = age;
    }

    @Override
    public String toString() {
        return "Emp{" +
                "id=" + id +
                ", name='" + name + '\'' +
                ", age=" + age +
                '}';
    }
}

//寫一個工具類DBUtils 裡面寫一個方法getDateSource() 用來獲取資料來源
 

package com.mchange.v2.log;
import com.mchange.v2.c3p0.ComboPooledDataSource;
import javax.sql.DataSource;

public class DBUtils {
    public static DataSource getDateSource(){
        DataSource ds = new ComboPooledDataSource();
        return ds;
    }
}

//寫一個員工資料訪問類 用來訪問資料庫 進行增刪改查
package com.mchange.v2.log;
import org.apache.commons.dbutils.QueryRunner;
import org.apache.commons.dbutils.handlers.BeanListHandler;
import java.sql.SQLException;
import java.util.List;

public class EmpDaoImpl {
    private QueryRunner qr = new QueryRunner(DBUtils.getDateSource());
    public List<Emp> getAllEmp(){
        String sql="select * from emp1";
        List<Emp> list=null;
        try {
            list= qr.query(sql, new BeanListHandler<>(Emp.class));

        } catch (SQLException throwables) {
            throwables.printStackTrace();
        }
            return list;
        }
    public int addEmp(Emp emp){
        String sql="insert into emp1 values(?,?,?)";
        int rows=0;
        try {
            rows=qr.update(sql,emp.getId(),emp.getName(),emp.getAge());
        } catch (SQLException throwables) {
            throwables.printStackTrace();
        }if (rows>0){
            System.out.println("新增成功！");

            EmpDaoImpl empDao=new EmpDaoImpl();
            for (Emp e:empDao.getAllEmp()) {
                System.out.println(e);
            }
        }else {
            System.out.println("新增失敗！");
        }
        return rows;
    }
    public int deleteEmp(int id){
        String sql="delete from emp1 where id=?";
        int rows=0;
        try {
            rows = qr.update(sql, id);
        } catch (SQLException throwables) {
            throwables.printStackTrace();
        }
        if (rows>0){
            System.out.println("刪除成功！");
            EmpDaoImpl empDao=new EmpDaoImpl();
            for (Emp e:empDao.getAllEmp()) {
                System.out.println(e);
            }
        }else {
            System.out.println("刪除失敗！");
        }
        return rows;
    }
    public int updataEmp(Emp emp){
        String sql="update emp1 set name=?,age=? where id=?";
        int rows=0;
        try {
            rows = qr.update(sql, emp.getName(), emp.getAge(), emp.getId());
        } catch (SQLException throwables) {
            throwables.printStackTrace();
        }
        if (rows>0){
            System.out.println("修改成功！");

            EmpDaoImpl empDao=new EmpDaoImpl();
            for (Emp e:empDao.getAllEmp()) {
                System.out.println(e);
            }
        }else {
            System.out.println("修改失敗！");
        }
        return rows;
    }
}

//寫一個降低日誌輸出等級類
package com.mchange.v2.log;
import java.util.logging.Level;

public class AmendLogLevel {
    public static void amendInfoLevel(Level level){
        MLevel.INFO.level=level;
    }
}

//寫個測試類 測試對員工資料進行增刪改查
package com.mchange.v2.log;
import java.util.logging.Level;

public class Test {
    static {
        AmendLogLevel.amendInfoLevel(Level.ALL);
    }
    public static void main(String[] args) {
        EmpDaoImpl empDao=new EmpDaoImpl();
        empDao.addEmp(new Emp(6,"daming",24));
        //empDao.deleteEmp(4);
        //empDao.updataEmp(new Emp(6,"xiaoming",20));
        //empDao.getAllEmp();
        //empDao.deleteEmp(5);
    }
}

說明:此方法在網上某位大佬學到的。。。