Spring JDBC---jdbcTemplate数据查询方法

查询单条数据

　jdbcTemplate.queryForObject()

查询复合数据

　jdbcTemplate.query()

无法进行实体类映射

　使用jdbcTemplate.queryForList()保存查询结果数据,结果封装成map对象

 

在EmployeeDao中增加查询方法

package com.spring.jdbc.dao;

import com.spring.jdbc.entity.Employee;
import org.springframework.jdbc.core.BeanPropertyRowMapper;
import org.springframework.jdbc.core.JdbcTemplate;

import java.util.List;
import java.util.Map;

public class EmployeeDao {
    private JdbcTemplate jdbcTemplate;

    public Employee findById(Integer eno){
        String sql = "select * from employee where eno = ?";
        //jdbcTemplate.queryForObject()查询单条数据
        Employee employee = jdbcTemplate.queryForObject(sql,new Object[]{eno},new BeanPropertyRowMapper<Employee>(Employee.class));
        return employee;
    }

    public List<Employee> findByDname(String dname){
        String sql = "select * from employee where dname = ?";
        //jdbcTemplate.query()查询复合数据
        List<Employee> list = jdbcTemplate.query(sql, new Object[]{dname}, new BeanPropertyRowMapper<Employee>(Employee.class));
        return list;
    }

    public List<Map<String, Object>> findMapByDname(String dname){
        String sql = "select eno as empno,salary as s from employee where dname = ?";
        //无法进行实体类映射，使用jdbcTemplate.queryForList()保存查询结果数据,结果封装成map对象
        List<Map<String, Object>> maps = jdbcTemplate.queryForList(sql, new Object[]{dname});
        return maps;
    }

    public JdbcTemplate getJdbcTemplate() {
        return jdbcTemplate;
    }

    public void setJdbcTemplate(JdbcTemplate jdbcTemplate) {
        this.jdbcTemplate = jdbcTemplate;
    }
}

在测试类中调用

import com.spring.jdbc.dao.EmployeeDao;
import com.spring.jdbc.entity.Employee;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.test.context.ContextConfiguration;
import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;

import javax.annotation.Resource;

@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration(locations = {"classpath:applicationContext.xml"})
public class JdbcTemplateTestor {
    @Resource
    private EmployeeDao employeeDao;

    @Test
    public void testFindById(){
        Employee employee = employeeDao.findById(3308);
        System.out.println(employee);
    }
    @Test
    public void testFindByDname(){
        System.out.println(employeeDao.findByDname("市场部"));
    }
    @Test
    public void testFindMapByDname(){
        System.out.println(employeeDao.findMapByDname("研发部"));
    }
}