SSM框架（Spring + SpringMVC + MyBatis）学习笔记，第三课：SpringJDBC

一、创建工程

1. 创建web工程

如何创建web工程，这里不细说，详情请参考第一课内容（https://blog.youkuaiyun.com/zj499063104/article/details/94493866）；

2. 引入jar包

ioc+aop+jdbc+dbcp（前面四个jar包，下载地址）+mysql数据库驱动包（MySQL官网下载）

3. 如果没有MySQL数据库，需要下载安装

二、案例编写

1. 配置applicationContext.xml

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
	xmlns:context="http://www.springframework.org/schema/context" xmlns:util="http://www.springframework.org/schema/util"  
	xmlns:jee="http://www.springframework.org/schema/jee" xmlns:tx="http://www.springframework.org/schema/tx"
	xmlns:jpa="http://www.springframework.org/schema/data/jpa" xmlns:mvc="http://www.springframework.org/schema/mvc"
	xsi:schemaLocation="
		http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.2.xsd
		http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.2.xsd
		http://www.springframework.org/schema/util http://www.springframework.org/schema/util/spring-util-3.2.xsd
		http://www.springframework.org/schema/jee http://www.springframework.org/schema/jee/spring-jee-3.2.xsd
		http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-3.2.xsd
		http://www.springframework.org/schema/data/jpa http://www.springframework.org/schema/data/jpa/spring-jpa-1.3.xsd
		http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc-3.2.xsd">

<!-- 开启组件扫描 -->
<context:component-scan base-package="cn.springjdbc"/>

<!-- 定义JdbcTemplate -->
<bean id="template" class="org.springframework.jdbc.core.JdbcTemplate">
	<property name="dataSource" ref="dbcp"></property>
</bean>

<!-- DataSource//数据源，连接池;dbcp,c3p0,proxool -->
<bean id="dbcp" class="org.apache.commons.dbcp.BasicDataSource">
	<property name="username" value="root"></property>
	<property name="password" value="asdf123456"></property>
	<property name="driverClassName" value="com.mysql.jdbc.Driver"></property>
	<property name="url" value="jdbc:mysql:///test"></property>
</bean>
</beans>

2. 编写实体类Emp.java

package cn.springjdbc.entity;

import java.io.Serializable;

public class Emp implements Serializable{
	private String name;
	private Integer sex;
	private Double salary;
	public String getName() {
		return name;
	}
	public void setName(String name) {
		this.name = name;
	}
	public Integer getSex() {
		return sex;
	}
	public void setSex(Integer sex) {
		this.sex = sex;
	}
	public Double getSalary() {
		return salary;
	}
	public void setSalary(Double salary) {
		this.salary = salary;
	}
	public Emp(String name, Integer sex, Double salary) {
		super();
		this.name = name;
		this.sex = sex;
		this.salary = salary;
	}
	
}

3.编写Dao方法

package cn.springjdbc.dao;

import java.util.List;

import javax.annotation.Resource;

import org.springframework.jdbc.core.JdbcTemplate;
import org.springframework.stereotype.Repository;

import cn.springjdbc.entity.Emp;

@Repository
public class EmpDao {
	
	@Resource
	private JdbcTemplate template;
	
	public void save(Emp emp) {
		String sql="insert into emp (name,sex,salary)values (?,?,?)";
		Object[] params = {emp.getName(),emp.getSex(),emp.getSalary()};
		template.update(sql, params);
	}
	
	public List<Emp> findAll(){
		String sql="select * from emp";
		EmpRowMapper rowMapper = new EmpRowMapper();
		List<Emp> lst = template.query(sql, rowMapper);
		return lst;
		
	}
	
	public List<Emp> findAllById(int id){
		String sql="select * from emp where id=?";
		EmpRowMapper rowMapper = new EmpRowMapper();
		Object[] params = {id};
		List<Emp> lst = template.query(sql, params, rowMapper);
		return lst;
	}
	
	public void deleteById(int id) {
		String sql ="delete from emp where id=?";
		Object[] obj = {id};
		template.update(sql, obj);
	}
}

package cn.springjdbc.dao;

import java.sql.ResultSet;
import java.sql.SQLException;

import org.springframework.jdbc.core.RowMapper;

import cn.springjdbc.entity.Emp;

public class EmpRowMapper implements RowMapper<Emp>{

	@Override
	public Emp mapRow(ResultSet rs, int arg1) throws SQLException {
		//将当前rs指针指向的记录取出,封装成Emp返回
		Emp emp = new Emp(rs.getString("name"),rs.getInt("sex"),rs.getDouble("salary"));
		return emp;
	}

}

4.编写测试类

package cn.springjdbc.test;

import java.util.List;

import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;

import cn.springjdbc.dao.EmpDao;
import cn.springjdbc.entity.Emp;

public class TestEmpDao {

	public static void main(String[] args) {
		ApplicationContext ac = new ClassPathXmlApplicationContext("applicationContext.xml");
		EmpDao empDao =ac.getBean("empDao", EmpDao.class);
//		Emp emp = new Emp("小红",0,5000.0);
//		empDao.save(emp);
		
//		List<Emp> list = empDao.findAll();
//		for(Emp emp : list) {
//			System.out.println(emp.getName()+", "+emp.getSex()+", "+emp.getSalary());
//		}
		
//		List<Emp> list = empDao.findAllById(1);
//		for(Emp emp : list) {
//			System.out.println(emp.getName()+", "+emp.getSex()+", "+emp.getSalary());
//		}
		
		empDao.deleteById(2);
	}
}