<plugins>

            <plugin>

                <!-- https://mvnrepository.com/artifact/org.apache.tomcat.maven/tomcat7-maven-plugin -->

                <groupId>org.apache.tomcat.maven</groupId>

                <artifactId>tomcat7-maven-plugin</artifactId>

                <version>2.2</version>

                <configuration>

                    <port>8888</port>

                </configuration>

            </plugin>

        </plugins>

实体类

package com.example.day_24_maavenmysql.domain;

public class Items {

    private Integer id;

    private String name;

    public Integer getId() {

        return id;

    }

    public void setId(Integer id) {

        this.id = id;

    }

    public String getName() {

        return name;

    }

    public void setName(String name) {

        this.name = name;

    }

}

接口

package com.example.day_24_maavenmysql.dao;

import com.example.day_24_maavenmysql.domain.Items;

import java.util.List;

public interface ItemsDao {

    public List<Items> findAll();

}

实现接口

package com.example.day_24_maavenmysql.dao.impl;

import com.example.day_24_maavenmysql.dao.ItemsDao;

import com.example.day_24_maavenmysql.domain.Items;

import java.sql.Connection;

import java.sql.DriverManager;

import java.sql.PreparedStatement;

import java.sql.ResultSet;

import java.util.ArrayList;

import java.util.List;

/**

 * 要想从数据库中取出数据

 * 必须有四个属性：数据库驱动，连接数据库的地址，数据库用户名称，数据库密码。

 */

public class ItemsDaoImpl implements ItemsDao {

    public List<Items> findAll(){

        List<Items> list = new ArrayList<Items>();

        //先获取contection对象

        Connection connection = null;

        //获取真正操作数据的对象

        PreparedStatement pst = null;

        //执行数据库查询操作

        ResultSet rs = null;

        try {

            //加载驱动类

            Class.forName("com.mysql.jdbc.Driver");

            //先获取contection对象

            connection = DriverManager.getConnection("jdbc:mysql:///kaohe","root", "root");

            //获取真正操作数据的对象

            pst = connection.prepareCall("select * from province");

            //执行数据库查询操作

           rs = pst.executeQuery();

            //把数据库结果集转成java的List集合

            while (rs.next()){

                Items items = new Items();

                items.setId(rs.getInt("id"));

                items.setName(rs.getString("name"));

                list.add(items);

            }

        }catch (Exception e){

            e.printStackTrace();

        }

        return list;

    }

}

测试类

import com.example.day_24_maavenmysql.dao.ItemsDao;

import com.example.day_24_maavenmysql.dao.impl.ItemsDaoImpl;

import com.example.day_24_maavenmysql.domain.Items;

import org.junit.Test;

import java.util.List;

public class ttest {

        @Test

        public void findAll(){

            ItemsDao itemsDao = new ItemsDaoImpl();

            List<Items> list = itemsDao.findAll();

            for (Items items : list) {

                System.out.println(items.getName());

            }

        }

    }