从网上找来的文章都是说通过@Value怎么注入属性值。

但是如果你有20多个属性值需要配置呢？写一串的@Value吗？

所以，就想先把属性注入到Map，再随用随取。代码如下，仅供测试

package com.xxxx;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.bind.RelaxedPropertyResolver;
import org.springframework.cloud.context.config.annotation.RefreshScope;
import org.springframework.context.EnvironmentAware;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.core.env.AbstractEnvironment;
import org.springframework.core.env.CompositePropertySource;
import org.springframework.core.env.Environment;
import org.springframework.core.env.MapPropertySource;

import java.util.HashMap;
import java.util.Map;
import java.util.Properties;

@Configuration
public class Config {

    @Autowired
    private Environment environment;

    public Properties setEnvironment() {
        final Properties properties = new Properties();
        ((AbstractEnvironment) environment).getPropertySources().forEach(propertySource -> {
            System.out.println(propertySource.getName()+", class: "+ propertySource.getClass().getName());
            if(propertySource instanceof CompositePropertySource){
                properties.putAll(getPropertiesInCompositePropertySource((CompositePropertySource) propertySource));
            }
        });
        System.out.println("-----------------------------------------------------------");
        properties.forEach((o, o2) -> {
            System.out.println("key: "+o+", value: "+o2);
        });
        System.out.println("-----------------------------------------------------------");
        return properties;
    }

    private Properties getPropertiesInCompositePropertySource(CompositePropertySource compositePropertySource){
        final Properties properties = new Properties();
        compositePropertySource.getPropertySources().forEach(propertySource -> {
            if (propertySource instanceof MapPropertySource) {
                properties.putAll(((MapPropertySource) propertySource).getSource());
            }
            if (propertySource instanceof CompositePropertySource)
                properties.putAll(getPropertiesInCompositePropertySource((CompositePropertySource) propertySource));
        });
        return properties;
    }

    @Bean
    @RefreshScope
    public ConfigMap configMap(){
        return new ConfigMap(setEnvironment());
    }

    public static class ConfigMap{
        private Properties properties;

        public ConfigMap(Properties properties) {
            this.properties = properties;
        }

        public String getKey(String key){
            return properties.getProperty(key);
        }

        public String getKeyOrDefault(String key, String defaultValue){
            return properties.getOrDefault(key, defaultValue).toString();
        }

        public String getKeyOnRequire(String key){
            if(!properties.containsKey(key)){
                throw new RuntimeException("the key is not found.");
            }
            return getKey(key);
        }

        public Map<String, String> getAllConfigs(){
            return new HashMap<>((Map) properties);
        }
    }
}

经过测试，可以动态刷新属性值。