SpringBoot配置参数绑定@ConfigurationProperties@Value

柔光的暖阳◎ 2022-09-06 01:14 228阅读 0赞

### 将spring配置文件中配置的参数绑定给组件的属性 ###

*   *  作用
     *  实现
     *   *  步骤
         *  注册组件
         *  参数绑定种类
     *  @Value和@ConfigurationProperties示例
     *  配置类@EnableConfigurationProperties+@ConfigurationProperties示例

## 作用 ##

*  将spring配置文件中配置的参数绑定给组件的属性

## 实现 ##

### 步骤 ###

1.  容器中注册组件
2.  参数绑定

### 注册组件 ###

*  @Component
 *  @Repository
 *  @Service
 *  @Controller
 *  @RestController
 *  @Configuration+@Bean
 *  等等

### 参数绑定种类 ###

*  单个属性绑定：组件+@Value
 *  批量属性绑定：组件+@ConfigurationProperties
 *  批量属性绑定：配置类@EnableConfigurationProperties+@ConfigurationProperties

**说明：容器组件@EnableConfigurationProperties+@ConfigurationProperties也是可以实现配置参数绑定功能，但是从系统设计角度不推荐这么做；就像@Component+@Bean也能实现组件注册功能一样能实现但是不推荐**

## @Value和@ConfigurationProperties示例 ##

*  待绑定属性的容器组件

package com.ultra.config;
    
    
    import org.springframework.beans.factory.annotation.Value;
    import org.springframework.boot.context.properties.ConfigurationProperties;
    import org.springframework.stereotype.Component;
    
    @Component
    @ConfigurationProperties(prefix = "user1")
    public class User { 
        private String name;
        @Value("use1.nickname")
        private String nickname;
    
        public String getName() { 
            return name;
        }
    
        public void setName(String name) { 
            this.name = name;
        }
    
        @Override
        public String toString() { 
            return "User{" +
                    "name='" + name + '\'' +
                    ", nickname='" + nickname + '\'' +
                    '}';
        }
    }

*  spring配置文件

user1.name=XiaoMing
    user1.nickname=XiaoBaiLong

*  测试类/启动类

package com.ultra;
    
    import com.ultra.config.User;
    import org.springframework.boot.SpringApplication;
    import org.springframework.boot.autoconfigure.SpringBootApplication;
    import org.springframework.context.ConfigurableApplicationContext;
    
    /** * @author admin */
    @SpringBootApplication
    public class SpringbootWebApplication { 
    
        public static void main(String[] args) { 
            ConfigurableApplicationContext applicationContext = SpringApplication.run(SpringbootWebApplication.class, args);
            User user = applicationContext.getBean(User.class);
            System.out.println(user);
        }
    }

*  结果  
    ![在这里插入图片描述][f9c0591737f642c08d8107b9c2e61ba9.png]

## 配置类@EnableConfigurationProperties+@ConfigurationProperties示例 ##

*  待绑定属性的容器组件

package com.ultra.config;
    
    
    import org.springframework.beans.factory.annotation.Value;
    import org.springframework.boot.context.properties.ConfigurationProperties;
    
    @ConfigurationProperties(prefix = "user1")
    public class User { 
        private String name;
        @Value("use1.nickname")
        private String nickname;
    
        public String getName() { 
            return name;
        }
    
        public void setName(String name) { 
            this.name = name;
        }
    
        @Override
        public String toString() { 
            return "User{" +
                    "name='" + name + '\'' +
                    ", nickname='" + nickname + '\'' +
                    '}';
        }
    }

*  spring配置文件

user1.name=XiaoMing
    user1.nickname=XiaoBaiLong

*  配置类

package com.ultra.config;
    
    import org.springframework.boot.context.properties.EnableConfigurationProperties;
    import org.springframework.context.annotation.Configuration;
    
    @Configuration
    @EnableConfigurationProperties({ User.class})
    public class UserConfig { 
    }

*  测试类/启动类

*  结果  
    ![在这里插入图片描述][184f1249148d4e33a37a227fd7b8ef14.png]

[f9c0591737f642c08d8107b9c2e61ba9.png]: /images/20220829/1e339e13a15944e3a94fb1ea1bb8724b.png
[184f1249148d4e33a37a227fd7b8ef14.png]: /images/20220829/bb120af3d5934455b8c6b54eca196691.png