选项1：通过环境后处理器执行：

假设您已在/resources/META-INF/spring.factories文件中注册了EnvironmentPostProcessor：
org.springframework.boot.env.EnvironmentPostProcessor=package.to.environment.config.EnvironmentConfig
您所需要的只是添加自定义PropertySource：

public class EnvironmentConfig implements EnvironmentPostProcessor {

    @Override
    public void postProcessEnvironment(ConfigurableEnvironment environment,
                                       SpringApplication application) {
        environment.getPropertySources()
                .addFirst(new CustomPropertySource("customPropertySource"));
    }
}

public class CustomPropertySource extends PropertySource<String> {
    public CustomPropertySource(String name) {
        super(name);
    }

    @Override
    public Object getProperty(String name) {
        if (name.equals("name")) {
            return "MY CUSTOM RUNTIME VALUE";
        }
        return null;
    }
}

选项2：通过属性资源占位符配置器执行此操作：

负责解析这些占位符的类是名为PropertySourcesPlaceholderConfigurer的BeanPostProcessor（请参见here）。
因此，您可以覆盖它并提供自定义的PropertySource，它将解析您所需的属性，如下所示：

@Component
public class CustomConfigurer extends PropertySourcesPlaceholderConfigurer {

    @Override
    protected void processProperties(ConfigurableListableBeanFactory beanFactoryToProcess, ConfigurablePropertyResolver propertyResolver) throws BeansException {
        ((ConfigurableEnvironment) beanFactoryToProcess.getBean("environment"))
                .getPropertySources()
                .addFirst(new CustomPropertySource("customPropertySource"));
        super.processProperties(beanFactoryToProcess, propertyResolver);
    }
}

使用ConfigurationProperties作为你的属性，并通过一个api修改它，如下所示：

@Component
@ConfigurationProperties(prefix = "user")
public class AppProperties {

    private String name;

    //getter and setter
}

@RestController
public class AppPropertiesController {
    @Autowire
    AppProperties prop;

    @PostMapping("/changeProp/{name}")
    public void change(@PathVariable String name){
        prop.setName(name);
    }
}