springboot中集成druid和mybatits

男娘i 2024-04-17 06:27 63阅读 0赞

# 一、创建springboot项目 #

1.  使用spring Initializer生成spring boot项目
2.  引入如下的依赖

<dependency>
                <groupId>com.alibaba</groupId>
                <artifactId>druid</artifactId>
                <version>1.1.19</version>
            </dependency>
    
            
            <dependency>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-starter-web</artifactId>
            </dependency>
            
            
            <dependency>
                <groupId>org.mybatis.spring.boot</groupId>
                <artifactId>mybatis-spring-boot-starter</artifactId>
                <version>2.1.0</version>
            </dependency>
    
            
            <dependency>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-devtools</artifactId>
                <scope>runtime</scope>
                <optional>true</optional>
            </dependency>
            
            <dependency>
                <groupId>mysql</groupId>
                <artifactId>mysql-connector-java</artifactId>
                <scope>runtime</scope>
            </dependency>
            
            <dependency>
                <groupId>org.projectlombok</groupId>
                <artifactId>lombok</artifactId>
                <optional>true</optional>
            </dependency>
            
            <dependency>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-starter-test</artifactId>
                <scope>test</scope>
            </dependency>

# 二、配置数据源druid #

> 1.添加application.yml配置文件(非必须，也可以在application.properties文件中添加)

> 2.添加如下的配置

spring:
      datasource:
        username: root #数据库用户名
        password: 1 # 数据库密码
        url: jdbc:mysql://192.168.43.243:3306/test #指定连接地址和数据库
        type: com.alibaba.druid.pool.DruidDataSource #指定数据源为druid
        # driver-class-name: com.mysql.cj.jdbc.Driver之前是需要指定数据库驱动类，我用的这个版本会自动识别，不需要填写这个属性
        
        # 如果没有进行第三步3的配置，下面的属性是不会生效的
        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，去掉后监控界面sql无法统计，'wall'用于防火墙
        #filters: stat,wall,log4j
        maxPoolPreparedStatementPerConnectionSize: 20
        useGlobalDataSourceStat: true
        connectionProperties: druid.stat.mergeSql=true;druid.stat.slowSqlMillis=500

> 3.添加druid配置类，让属性生效

import com.alibaba.druid.pool.DruidDataSource;
    import com.alibaba.druid.support.http.StatViewServlet;
    import com.alibaba.druid.support.http.WebStatFilter;
    import org.springframework.boot.context.properties.ConfigurationProperties;
    import org.springframework.boot.web.servlet.FilterRegistrationBean;
    import org.springframework.boot.web.servlet.ServletRegistrationBean;
    import org.springframework.context.annotation.Bean;
    import org.springframework.context.annotation.Configuration;
    
    import javax.sql.DataSource;
    import java.util.Arrays;
    import java.util.HashMap;
    import java.util.Map;
    
    @Configuration
    public class DruidConfig { 
    
        @ConfigurationProperties(prefix = "spring.datasource") //将spring.datasource下的属性自动配置到druid中
        @Bean
        public DataSource druid(){ 
            return new DruidDataSource();
        }
    }

> 4.配置druid后台管理服务

//配置Druid的监控
        //1.配置一个管理后台的servlet
        @Bean
        public ServletRegistrationBean statViewServlet(){ 
            ServletRegistrationBean bean = new ServletRegistrationBean(new StatViewServlet(), "/druid/*");
            
            Map<String,String> initParams = new HashMap<String, String>() { { 
                put("loginUsername", "admin");
                put("loginPassword", "123456");
                put("allow", "");
                put("deny", "192.168.23.243");
            }};
            bean.setInitParameters(initParams);
    
            return bean;
        }
    
    
        //2.配置一个监控的filter
        @Bean
        public FilterRegistrationBean druidFilter(){ 
            FilterRegistrationBean filterRegistrationBean = new FilterRegistrationBean();
            filterRegistrationBean.setFilter(new WebStatFilter());
            
            Map<String,String> initParams = new HashMap<String,String>(){ { 
                put("exclusion","*.js,*.css,/druid/*");
            }};
            filterRegistrationBean.setInitParameters(initParams);
            filterRegistrationBean.setUrlPatterns(Arrays.asList("/*"));
            return filterRegistrationBean;
        }

> 5.查看是否配置成功

1.  启动服务器
2.  访问如下地址：http://localhost:8080/druid/login.html
3.  进入登录界面(用户名和密码就是刚才设置的loginUsername和loginPassword)  
    ![image][]
4.  登录后进入如下界面  
    ![image][image 1]
5.  出现上面的界面表示配置成功

# 三、配置Mybatits(注解版) #

> 1 编写一个entity

import lombok.Data;
    
    import javax.validation.constraints.NotNull;
    
    @Data
    public class User { 
        private Integer id;
        @NotNull
        private String userName;
    }

> 2 编写一个mapper接口

import com.example.druid.entity.User;
    import org.apache.ibatis.annotations.*;
    
    import java.util.List;
    
    @Mapper
    public interface UserMapper { 
    
        @Select("SELECT * FROM user WHERE id = #{id}")
        User getUserById(Integer id);
    
        @Options(useGeneratedKeys = true,keyProperty = "id")
        @Insert("INSERT INTO user(id,userName) values(#{id},#{userName})")
        int saveUser(User user);
    
        @Update("UPDATE user set userName=#{userName} where id=#{id}")
        int updateUser(User user);
    
        @Delete("DELETE FROM user WHERE id=#{id}")
        int deleteUserById(Integer id);
    
        @Select("SELECT * FROM user")
        List<User> getAll();
    }

> 3 service层

import com.example.druid.entity.User;
    import com.example.druid.mapper.UserMapper;
    import com.example.druid.service.UserService;
    import org.springframework.beans.factory.annotation.Autowired;
    import org.springframework.stereotype.Service;
    
    import java.util.List;
    
    @Service
    public class UserServiceImpl implements UserService { 
    
        @Autowired
        private UserMapper userMapper;
    
        @Override
        public User getUserById(Integer id) { 
            return userMapper.getUserById(id);
        }
    
        @Override
        public List<User> getAll() { 
            return userMapper.getAll();
        }
    
        @Override
        public int save(User user) { 
            return userMapper.saveUser(user);
        }
    
        @Override
        public int update(User user) { 
            return userMapper.updateUser(user);
        }
    
        @Override
        public int delete(int id) { 
            return userMapper.deleteUserById(id);
        }
    }

> 4 controller层

import com.example.druid.entity.User;
    import com.example.druid.service.UserService;
    import org.springframework.beans.factory.annotation.Autowired;
    import org.springframework.web.bind.annotation.*;
    
    import java.util.List;
    
    @RestController
    public class UserController { 
    
        @Autowired
        private UserService userService;
    
        @GetMapping("/user")
        public User getUser(@RequestParam Integer id){ 
            return userService.getUserById(id);
        }
    
        @GetMapping("/users")
        public List<User> getAll(){ 
            return userService.getAll();
        }
    
        @PostMapping("/user")
        public int saveUser(@RequestBody User user){ 
            return userService.save(user);
        }
    
        @PutMapping("/user")
        public int updateUser(@RequestBody User user){ 
            return userService.update(user);
        }
    
        @DeleteMapping("/user")
        public int deleteUser(@RequestParam int id){ 
            return userService.delete(id);
        }
    
    }

> 5 打印结果

{ "id":2,"userName":"lsr"}
    [{ "id":1,"userName":"ljl"},{ "id":2,"userName":"lsr"}]

# 四、配置Mybatits(配置文件版) #

> 1.  在application.yml文件中添加如下的配置

mybatis:
      config‐location: classpath:mybatis/mybatis‐config.xml # 指定全局配置文件的位置
      mapper‐locations: classpath:mybatis/mapper/*.xml # 指定sql映射文件的位置

> 1.  在mybatis-config.xml添加如下的配置

<?xml version="1.0" encoding="UTF-8" ?>
    <!DOCTYPE configuration PUBLIC "-//mybatis.org//DTD Config 3.0//EN" "http://mybatis.org/dtd/mybatis-3-config.dtd">
    <configuration>
      <settings>
        <setting name="mapUnderscoreToCamelCase" value="true"/>
      </settings>
    </configuration>

> 1.  UserMapper接口类

import com.example.druid.entity.User;
    import org.apache.ibatis.annotations.*;
    
    import java.util.List;
    
    @Mapper
    public interface UserMapper { 
    
        //@Select("SELECT * FROM user WHERE id = #{id}")
        User getUserById(Integer id);
    
        //@Options(useGeneratedKeys = true,keyProperty = "id")
        //@Insert("INSERT INTO user(id,userName) values(#{id},#{userName})")
        int saveUser(User user);
    
        //@Update("UPDATE user set userName=#{userName} where id=#{id}")
        int updateUser(User user);
    
        //@Delete("DELETE FROM user WHERE id=#{id}")
        int deleteUserById(Integer id);
    
        //@Select("SELECT * FROM user")
        List<User> getAll();
    }

> 1.  UserMapper.xml添加如下的配置

<?xml version="1.0" encoding="UTF-8" ?>
    <!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN" "http://mybatis.org/dtd/mybatis-3-mapper.dtd">
    <mapper namespace="com.example.druid.mapper.UserMapper">
        <select id="getUserById" resultType="com.example.druid.entity.User">
          SELECT * FROM user WHERE id = #{id}
        </select>
        <select id="getAll" resultType="com.example.druid.entity.User">
            SELECT * FROM user
        </select>
        <insert id="saveUser">
            INSERT INTO user(id,userName) values(#{id},#{userName})
        </insert>
        <update id="updateUser">
            UPDATE user set userName=#{userName} where id=#{id}
        </update>
        <delete id="deleteUserById">
            DELETE FROM user WHERE id=#{id}
        </delete>
    </mapper>

# 五、总结 #

值得注意的是注解和配置文件的方式是可以共存的，注解版相对方便很多，但是配置动态sql就比较难，配置文件可以很方便的实现，因此两种共用比较好，简单的就使用注解版，需要动态sql的配置文件。mysql有逆向工程，可以自动生成配置文件，之后会做相应的介绍。

[image]: https://imgconvert.csdnimg.cn/aHR0cHM6Ly9ub3RlLnlvdWRhby5jb20veXdzL3B1YmxpYy9yZXNvdXJjZS9hYTQ3MGFjNTAwZTU5MWJiYzdhNjIzZmFlYTNhNWNmYi94bWxub3RlLzlDN0FFRUY4NzExNzQwRDhBQjI3OEVEQURGRkUxQ0MwLzg5OTc?x-oss-process=image/format,png
[image 1]: https://imgconvert.csdnimg.cn/aHR0cHM6Ly9ub3RlLnlvdWRhby5jb20veXdzL3B1YmxpYy9yZXNvdXJjZS84Y2FhOGRiNTI3OWM5Nzc2ODIyYmFmNmVmMzkzOTljOC94bWxub3RlLzBFMUVDOUZGQkZBNzQ5ODk5RjU3MkQ5QjYxNEM5RTY3LzkwMDc?x-oss-process=image/format,png