springboot整合数据库

Posted 2021-03-07 pinked

springboot整合数据库

整合jdbc

1. 依赖

   <dependency>
       <groupId>org.springframework.boot</groupId>
       <artifactId>spring-boot-starter-jdbc</artifactId>
   </dependency>
   
   <dependency>
       <groupId>mysql</groupId>
       <artifactId>mysql-connector-java</artifactId>
       <scope>runtime</scope>
   </dependency>

2. 配置

   spring:
     datasource:
       username: root
       password: 123456
       url: jdbc:mysql://localhost:3306/mybatis?userUnicode=true&characterEncoding=utf-8
       driver-class-name: com.mysql.cj.jdbc.Driver

3. controller实现CRUD

   @Autowired
   JdbcTemplate jdbcTemplate;
   
   @RequestMapping("userlist")
   public List<Map<String, Object>> list() {
       String sql = "select * from user";
       List<Map<String, Object>> maps = jdbcTemplate.queryForList(sql);
       return maps;
   }
   
   @RequestMapping("add")
   public String addUser() {
       String sql = "insert into mybatis.user(id,name,pwd) values (5,'王五','123456')";
       int update = jdbcTemplate.update(sql);
       return "update";
   }
   
   @RequestMapping("update/{id}")
   public String updateUser(@PathVariable("id") int id) {
       String sql = "update mybatis.user set name = ?, pwd = ? where id =" + id;
       Object[] objects = new Object[2];
       objects[0] = "野原新之助";
       objects[1] = "8848";
       int update = jdbcTemplate.update(sql, objects);
       return "update";
   }
   
   @RequestMapping("delete/{id}")
   public String deleteUser(@PathVariable("id") int id) {
       String sql = "delete from mybatis.user where id=?";
       int update = jdbcTemplate.update(sql, id);
       return "delete";
   }

整合druid

springboot默认使用hikari作为数据源,但也可以使用其他数据源,只需要修改配置文件中spring.datasource.type屬性即可

1. 依赖

   <dependency>
       <groupId>log4j</groupId>
       <artifactId>log4j</artifactId>
       <version>1.2.17</version>
   </dependency>
   
   <dependency>
       <groupId>com.alibaba</groupId>
       <artifactId>druid</artifactId>
       <version>1.1.21</version>
   </dependency>

2. application配置文件

   spring:
     datasource:
       username: root
       password: 123456
       url: jdbc:mysql://localhost:3306/mybatis?userUnicode=true&characterEncoding=utf-8
       driver-class-name: com.mysql.cj.jdbc.Driver
       type: com.alibaba.druid.pool.DruidDataSource
   
       #Spring Boot 默认是不注入这些属性值的，需要自己绑定
       #druid 数据源专有配置
       initialSize: 5
       minIdle: 5
       maxActive: 20
       maxWait: 60000
       timeBetweenEvictionRunsMillis: 60000
       minEvictableIdleTimeMillis: 300000
       validationQuery: SELECT 1 FROM DUAL
       testWhileIdle: true
       testOnBorrow: false
       testOnReturn: false
       poolPreparedStatements: true
   
       #配置监控统计拦截的filters，stat:监控统计、log4j：日志记录、wall：防御sql注入
       #如果允许时报错  java.lang.ClassNotFoundException: org.apache.log4j.Priority
       #则导入 log4j 依赖即可，Maven 地址： https://mvnrepository.com/artifact/log4j/log4j
       filters: stat,wall,log4j
       maxPoolPreparedStatementPerConnectionSize: 20
       useGlobalDataSourceStat: true
       connectionProperties: druid.stat.mergeSql=true;druid.stat.slowSqlMillis=500

3. druid配置

   @Configuration
   public class DruidConfig {
   
       @ConfigurationProperties(prefix = "spring.datasource")
       @Bean
       public DataSource druidDataSource(){
           return new DruidDataSource();
       }
   
       //后台监控
       @Bean
       public ServletRegistrationBean statViewServlet(){
           ServletRegistrationBean<StatViewServlet> bean = new ServletRegistrationBean<>(new StatViewServlet(), "/druid/*");
           //管理配置
           HashMap<String, String> hashMap = new HashMap<>();
           //增加配置
           hashMap.put("loginUsername", "admin");
           hashMap.put("loginPassword", "123456");
           //访问等级v值为空时所有人都能访问,localhost为限本机访问
           hashMap.put("allow", "");
           bean.setInitParameters(hashMap);//初始化参数
           return bean;
       }
   }

---

整合mybatis

1. 依赖

   <dependency>
       <groupId>org.mybatis.spring.boot</groupId>
       <artifactId>mybatis-spring-boot-starter</artifactId>
       <version>2.1.1</version>
   </dependency>

2. 配置

   spring:
     datasource:
       username: root
       password: 123456
       url: jdbc:mysql://localhost:3306/mybatis?userUnicode=true&characterEncoding=utf-8
       driver-class-name: com.mysql.cj.jdbc.Driver
   
   mybatis:
     type-aliases-package: cn.pinked.pojo
     mapper-locations: classpath:mybatis/mapper/*.xml

3. UserMapper接口

   @Mapper
   @Repository
   public interface UserMapper {
       List<User> queryUserList();
       User queryUserById(int id);
       int addUser(User user);
       int updateUser(User user);
       int deleteUser(int id);
   }

4. UserMapper.xml

   <?xml version="1.0" encoding="UTF-8" ?>
   <!DOCTYPE mapper
           PUBLIC "-//mybatis.org//DTD Config 3.0//EN"
           "http://mybatis.org/dtd/mybatis-3-mapper.dtd">
   <mapper namespace="cn.pinked.mapper.UserMapper">
   
       <select id="queryUserList" resultType="User">
           select * from mybatis.user
       </select>
   
       <select id="queryUserById" resultType="User">
           select * from mybatis.user where id = #{id}
       </select>
   
       <insert id="addUser" parameterType="User">
           insert into mybatis.user (id, name, pwd) values (#{id}, #{name}, #{pwd});
       </insert>
   
       <update id="updateUser" parameterType="User">
           update mybatis.user set name = #{name}, pwd = #{pwd} where id = #{id};
       </update>
   
       <delete id="deleteUser">
           delete from mybatis.user where id = #{id}
       </delete>
   
   </mapper>

5. service层

6. controller层