@ConfigurationProperties、@PropertySource注解的使用

深碍√TFBOYSˉ_ 2022-01-22 07:59 287阅读 0赞

**@ConfigurationProperties**(prefix = "person.dog")注解来修饰某类bean，其作用是告诉springBoot，获取配置文件中属性值，然后此类中的属性将与配置文件中对应属性一一绑定。【prefix = "person.dog"】表示与配置文件中哪个层级的属性进行绑定。如果是在主配置文件中(属性名必须是application.yml或application.properties)可以直接使用，实际生产中因为项目中一些属性为了直观区分，需自定义一个配置文件，例如redis.properties，这些属性在自定义的 配置文件中的，则需要配合**@PropertySource**使用.

默认Spring只读取主配置文件的属性，因此要引入自定义配置文件则要使用**@PropertySource**注解，并指定自定义配置文件路径，这样就可以将指定配置文件的属性读取到Spring中以供使用。我们可以通过environment.getProperty("env.name")，获取指定属性的值。也可以配合**@Value** 注解将Spring容器中读取到的值赋值给bean的属性。这种方式适合主要注入的属性少的场景，如果bean属性很多，那么要一个个的给属性标注@Value注解，过于繁琐，可以直接使用**@ConfigurationProperties**(prefix = "person.dog")自动适配属性。

person.properties配置文件内容

person.lastName=summer
    person.age=18
    person.address=南京
    person.desc=${person.lastName} from  ${person.address} and his age is ${person.age} and he has a cute dog named ${person.dog.name}
    
    person.dog.name=花花
    person.dog.age=8
    
    env.name=summer_env

1.通过**@PropertySource** 引入配置文件 配合**@Value** 注解注入值

package com.summerSpringBoot.demo.pojo;
    
    import org.springframework.beans.factory.annotation.Value;
    import org.springframework.context.annotation.PropertySource;
    import org.springframework.stereotype.Component;
    
    @PropertySource(value = { "classpath:person.properties" })
    @Component
    public class Person {
    
    	@Value("${person.lastName}")
    	private String name;
    	@Value("${person.age}")
    	private int age;
    	@Value("${person.address}")
    	private String address;
    	@Value("${person.desc}")
    	private String desc;
    
    	public void setAge(int age) {
    		this.age = age;
    	}
    
    	public void setName(String name) {
    		this.name = name;
    	}
    
    	public int getAge() {
    		return age;
    	}
    
    	public String getName() {
    		return name;
    	}
    
    	public void setAddress(String address) {
    		this.address = address;
    	}
    
    	public String getAddress() {
    		return address;
    	}
    
    	public String getDesc() {
    		return desc;
    	}
    
    	public void setDesc(String desc) {
    		this.desc = desc;
    	}
    
    }

2.直接通过**@PropertySource** 引入配置文件 配合**@ConfigurationProperties**(prefix = "person.dog") 自动赋值

package com.summerSpringBoot.demo.pojo;
    
    
    import org.springframework.boot.context.properties.ConfigurationProperties;
    import org.springframework.context.annotation.PropertySource;
    import org.springframework.stereotype.Component;
    
    @Component
    @PropertySource(value={ "classpath:person.properties" },encoding = "utf-8")
    @ConfigurationProperties(prefix = "person.dog")
    public class Dog {
        private String name;
        private int age;
    
        public String getName() {
            return name;
        }
    
        public void setName(String name) {
            this.name = name;
        }
    
        public int getAge() {
            return age;
        }
    
        public void setAge(int age) {
            this.age = age;
        }
    }

package com.summerSpringBoot.demo.controller;
    
    import java.util.HashMap;
    import java.util.List;
    import java.util.Map;
    import java.util.UUID;
    
    
    
    import org.springframework.beans.factory.annotation.Autowired;
    import org.springframework.beans.factory.annotation.Value;
    import org.springframework.core.env.Environment;
    import org.springframework.web.bind.annotation.PathVariable;
    import org.springframework.web.bind.annotation.RequestBody;
    import org.springframework.web.bind.annotation.RequestMapping;
    import org.springframework.web.bind.annotation.RestController;
    
    import com.alibaba.druid.stat.TableStat.Name;
    import com.summerSpringBoot.demo.pojo.Dog;
    import com.summerSpringBoot.demo.pojo.Order;
    import com.summerSpringBoot.demo.pojo.Person;
    import com.summerSpringBoot.demo.pojo.User;
    
    @RestController
    public class UserController {
    
    	@Value("${person.lastName}")
    	private String lastName;
    	@Autowired
    	private Person person;
    	@Autowired
    	private Dog dog;
    	@Autowired
    	private Environment environment;
    	
    
    	@RequestMapping("/")
    	public Map index() {
    		Map<String, Object> map = new HashMap<>();
    
    		map.put("id", UUID.randomUUID().toString());
    		map.put("name", lastName);
    		map.put("person", person);
    		map.put("dog", dog);
    		String property = environment.getProperty("env.name");
    		map.put("env", property);
    		return map;
    	}
    
    	
    }

访问：[http://127.0.0.1/summer/][http_127.0.0.1_summer]   可以成功拿到值

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3lrNjE0Mjk0ODYx_size_16_color_FFFFFF_t_70][]

[http_127.0.0.1_summer]: http://127.0.0.1/summer/
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3lrNjE0Mjk0ODYx_size_16_color_FFFFFF_t_70]: /images/20220122/f404360abd474f989a6b004b7942869c.png