调用的包

  <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-context</artifactId>
            <version>4.2.6.RELEASE</version>
        </dependency>
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>4.12</version>
            <scope>test</scope>
        </dependency>


        <!-- https://mvnrepository.com/artifact/com.mchange/c3p0 -->
        <dependency>
            <groupId>com.mchange</groupId>
            <artifactId>c3p0</artifactId>
            <version>0.9.5.2</version>
        </dependency>


        
        <!-- https://mvnrepository.com/artifact/mysql/mysql-connector-java -->
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>5.1.47</version>
        </dependency>


        <!-- https://mvnrepository.com/artifact/org.springframework/spring-jdbc -->
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-jdbc</artifactId>
            <version>5.1.4.RELEASE</version>
        </dependency>

查询、批量查询、更新（添加、删除、修改）的实现方式

package top.biglin.jdbctest;

import org.junit.Test;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;
import org.springframework.jdbc.core.BeanPropertyRowMapper;
import org.springframework.jdbc.core.JdbcTemplate;
import org.springframework.jdbc.core.RowMapper;
import top.biglin.spring.jdbc.Employee;

import javax.sql.DataSource;
import java.sql.SQLException;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;

/**
 * @author Chiawei
 * @date 2019/1/14 13:12
 */
public class JDBCTest {

    private ApplicationContext ctx = null;
    private JdbcTemplate jdbcTemplate;

    {
        ctx = new ClassPathXmlApplicationContext("applicationContext.xml");
        jdbcTemplate = (JdbcTemplate) ctx.getBean("jdbcTemplate");
    }

    /**
     * 获取单个的值
     */
    @Test
    public void testQueryForObject2(){
        String sql = "SELECT count(id) FROM employee";
        long count = jdbcTemplate.queryForObject(sql, Long.class);

        System.out.println(count);

    }

    /**
     * 从数据库中查询一组对象
     */
    @Test
    public void testQueryForList(){
//        String sql = "SELECT id,last_name lastName,email, dept_id as \"department\" FROM employee ";
        String sql = "SELECT id,last_name lastName,email FROM employee where id > ?";
        RowMapper<Employee> rowMapper = new BeanPropertyRowMapper<Employee>(Employee.class);
        List<Employee> employees = jdbcTemplate.query(sql, rowMapper, 2);
        System.out.println(employees);
    }


    /**
     * 从数据库中获取一条记录，实际得到对应的一个对象
     */
    @Test
    public void testQueryForObject(){
        String sql = "SELECT id,last_name lastName,email FROM employee WHERE id = ? ";
        RowMapper<Employee> rowMapper = new BeanPropertyRowMapper<Employee>(Employee.class);
        Employee employee = jdbcTemplate.queryForObject(sql, rowMapper, 1);

        System.out.println(employee);
    }

    @Test
    public void testBatchUpdate(){
        String sql = "INSERT INTO employee(id, last_name,email) values(?, ?, ?)";
        List<Object[]> batchArgs = new ArrayList<Object[]>();

        batchArgs.add(new Object[]{1,"AA", "1534369714@qq.com"});
        batchArgs.add(new Object[]{2,"BB", "1534369714@qq.com"});
        batchArgs.add(new Object[]{3,"CC", "1534369714@qq.com"});
        batchArgs.add(new Object[]{4,"DD", "1534369714@qq.com"});

        int[] result;
        result = jdbcTemplate.batchUpdate(sql,batchArgs);

        System.out.println(result[0]);
        for (int i:
             result) {
            System.out.println(i);
        }
    }

    @Test
    public void testUpdate(){
        String sql = "UPDATE administrator SET name = ? WHERE id = ?";
        int result = jdbcTemplate.update(sql, "Jack", 2);
        System.out.println("Update " + result + " rows");
    }
    @Test
    public void testJDBC() throws SQLException {
        DataSource dataSource = ctx.getBean(DataSource.class);
        System.out.println(dataSource.getConnection());

        System.out.println("JDBCTest...");
    }
}

实际开发中如何写Dao

package top.biglin.spring.jdbc;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.jdbc.core.BeanPropertyRowMapper;
import org.springframework.jdbc.core.JdbcTemplate;
import org.springframework.jdbc.core.RowMapper;
import org.springframework.stereotype.Repository;

/**
 * @author Chiawei
 * @date 2019/1/14 16:39
 */
@Repository
public class EmployeeDao {

    @Autowired
    private JdbcTemplate jdbcTemplate;

    public Employee get(Integer id) {
        String sql = "SELECT id,last_name lastName,email FROM employee WHERE id = ? ";
        RowMapper<Employee> rowMapper = new BeanPropertyRowMapper<Employee>(Employee.class);
        Employee employee = jdbcTemplate.queryForObject(sql, rowMapper, 1);

        return employee;
    }
}