创建Spring项目并连接数据库
1 先开启Mysql
首先按下电脑的win键,输入cmd,在显示出来的命令提示符里,鼠标右键选择以管理员方式打开。
然后再输入命令,net start MySQL。
2 打开图形化界面工具Navicat
先创建一个数据库,数据库的字符集选择utf-8,然后再在数据库中建表,在创建主键的时候,选择自动递增 ,最后再保存数据库。
3 打开IDEA,创建Spring的项目
4 导入相关依赖包
<dependency><groupId>org.springframework</groupId><artifactId>spring-core</artifactId><version>5.3.8</version></dependency><dependency><groupId>org.springframework</groupId><artifactId>spring-beans</artifactId><version>5.3.8</version></dependency><dependency><groupId>org.springframework</groupId><artifactId>spring-context</artifactId><version>5.3.8</version></dependency><dependency><groupId>org.springframework</groupId><artifactId>spring-context-support</artifactId><version>5.3.8</version></dependency><dependency><groupId>org.springframework</groupId><artifactId>spring-expression</artifactId><version>5.3.8</version></dependency><dependency><groupId>commons-logging</groupId><artifactId>commons-logging</artifactId><version>1.2</version></dependency><dependency><groupId>mysql</groupId><artifactId>mysql-connector-java</artifactId><version>8.0.20</version></dependency><dependency><groupId>org.springframework</groupId><artifactId>spring-jdbc</artifactId><version>5.3.8</version></dependency><dependency><groupId>org.springframework</groupId><artifactId>spring-tx</artifactId><version>5.3.8</version></dependency><dependency><groupId>org.springframework</groupId><artifactId>spring-aop</artifactId><version>5.3.8</version></dependency>
5 创建Spring Config
6 进行Spring的配置,在applicationContext中
其中的数据库名称和密码要根据你自己创建的做相应的改变
<!-- 1.配置数据源 --><beanclass="org.springframework.jdbc.datasource.DriverManagerDataSource"id="dataSource"><!-- 1.1.数据库驱动 --><propertyname="driverClassName"value="com.mysql.cj.jdbc.Driver"/><!-- 1.2.连接数据库的url --><propertyname="url"value="jdbc:mysql://localhost:3306/spring?characterEncoding=utf8&serverTimezone=UTC"/><!-- 1.3.连接数据库的用户名 --><propertyname="username"value="root"></property><!-- 1.4.连接数据库的密码 --><propertyname="password"value="123456"></property></bean><!-- 2配置JDBC模板 --><beanid="jdbcTemplate"class="org.springframework.jdbc.core.JdbcTemplate"><!-- 默认必须使用数据源 --><propertyname="dataSource"ref="dataSource"></property></bean>
7 创建类和Dao层
Dao层
packagecom.springjdbc;importorg.springframework.beans.factory.annotation.Autowired;importorg.springframework.jdbc.core.BeanPropertyRowMapper;importorg.springframework.jdbc.core.JdbcTemplate;importorg.springframework.jdbc.core.RowMapper;importorg.springframework.stereotype.Repository;importjava.sql.ResultSet;importjava.sql.SQLException;importjava.util.List;//用注解创建的对象就是类本身的类型,名字就是这个类的名字,首字母小写personDao@RepositorypublicclassPersonDao{// 1 实现依赖注入// 2 生成成员变量get和set方法// 3 实现自动注入 byType->byName (@Resource功能类似,只是该注解优先采用根据名称自动装配)@AutowiredJdbcTemplate jdbcTemplate;publicList<Person>findAllUser(){RowMapper<Person> rowMapper=newBeanPropertyRowMapper<>(Person.class);return jdbcTemplate.query("select * from person",rowMapper);}publicvoidaddUser(String name,int age){
jdbcTemplate.update("insert into person values (null,?,?)",age,name);}//?为占位符publicvoidupdateUser(String name,int age,int id){
jdbcTemplate.update("update person set name = ?,age = ? where id = ?",name,age,id);}publicvoiddeleteUser(int id){
jdbcTemplate.update("delete from person where id = ?",id);}}
类层
packagecom.springjdbc;publicclassPerson{privateint id;publicintgetId(){return id;}publicvoidsetId(int id){this.id= id;}publicintgetAge(){return age;}publicvoidsetAge(int age){this.age= age;}publicStringgetName(){return name;}publicvoidsetName(String name){this.name= name;}privateint age;privateString name;}
App层
packagecom.springjdbc;importorg.springframework.context.ApplicationContext;importorg.springframework.context.support.ClassPathXmlApplicationContext;importjava.util.List;/**
* Hello world!
*
*/publicclassApp{publicstaticvoidmain(String[] args){ApplicationContext applicationContext=newClassPathXmlApplicationContext("applicationContext.xml");//加载spring容器,创建对象PersonDao personDao=(PersonDao) applicationContext.getBean("personDao");
personDao.addUser("小花",18);// personDao.updateUser("小光",20,1);// personDao.deleteUser(1);List<Person> personList= personDao.findAllUser();for(Person person: personList){System.out.println(person.getName()+" "+person.getAge());}System.out.println("Hello World!");}}
applicationContext
<?xml version="1.0" encoding="UTF-8"?><beansxmlns="http://www.springframework.org/schema/beans"xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"xmlns:context="http://www.springframework.org/schema/context"xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd http://www.springframework.org/schema/context https://www.springframework.org/schema/context/spring-context.xsd"><!-- 通过注解的方式配置bean更加简洁优雅,是开发中常用的方式--><context:component-scanbase-package="com.springjdbc"/><!-- 1.配置数据源 --><beanclass="org.springframework.jdbc.datasource.DriverManagerDataSource"id="dataSource"><!-- 1.1.数据库驱动 --><propertyname="driverClassName"value="com.mysql.cj.jdbc.Driver"/><!-- 1.2.连接数据库的url --><propertyname="url"value="jdbc:mysql://localhost:3308/spring?characterEncoding=utf8&serverTimezone=UTC"/><!-- 1.3.连接数据库的用户名 --><propertyname="username"value="root"></property><!-- 1.4.连接数据库的密码 --><propertyname="password"value="123456"></property></bean><!-- 2配置JDBC模板 --><beanid="jdbcTemplate"class="org.springframework.jdbc.core.JdbcTemplate"><!-- 默认必须使用数据源 --><propertyname="dataSource"ref="dataSource"></property></bean></beans>