spring boot启动时加载外部配置文件

前言

相信很多人选择Spring Boot主要是考虑到它既能兼顾Spring的强大功能，还能实现快速开发的便捷。本文主要给大家介绍了关于spring boot启动时加载外部配置文件的相关内容，话不多说。

业务需求

加载外部配置文件，部署时更改比较方便。

上代码

@SpringBootApplication
public class Application {

 public static void main(String[] args) throws Exception {
  SpringApplicationBuilder springApplicationBuilder = new SpringApplicationBuilder(Application.class);
  springApplicationBuilder.web(true);
  Properties properties = getProperties();
  StandardEnvironment environment = new StandardEnvironment();
  environment.getPropertySources().addLast(new PropertiesPropertySource("micro-service", properties));
  springApplicationBuilder.environment(environment);
  springApplicationBuilder.run(args);
 }

 private static Properties getProperties() throws IOException {
  PropertiesFactoryBean propertiesFactoryBean = new PropertiesFactoryBean();
  ResourcePatternResolver resolver = new PathMatchingResourcePatternResolver();
  propertiesFactoryBean.setIgnoreResourceNotFound(true);
  Resource fileSystemResource = resolver.getResource("file:/opt/company/test.properties");
  propertiesFactoryBean.setLocations(fileSystemResource);
  propertiesFactoryBean.afterPropertiesSet();
  return propertiesFactoryBean.getObject();
 }
}

注意resolver.getResource("file:/opt/company/test.properties");需要加入file:，否则读不到。

使用变量的工具类

@Component
public class EnvironmentUtil {
 private static Environment environment;
 @Autowired
 public void setEnvironment(Environment environment) {
  EnvironmentUtil.environment = environment;
 }

 public static <T> T getProperty(String key, Class<T> targetType, T defaultValue) {
  return environment.getProperty(key, targetType, defaultValue);
 }

 public static <T> T getProperty(String key, Class<T> targetType) {
  return environment.getProperty(key, targetType);
 }

 public static String getProperty(String key) {
  return environment.getProperty(key);
 }

 public static String getProperty(String key, String defaultValue) {
  return environment.getProperty(key, defaultValue);
 }

 public static Integer getInteger(String key, Integer defaultValue) {
  return environment.getProperty(key, Integer.class, defaultValue);
 }
}

也可以通过@Value("${key}")使用

这中加载方法优先级很高，如果与spring boot配置文件同名，将覆盖application.properties文件中的配置。

总结

以上就是这篇文章的全部内容了，希望本文的内容对大家的学习或者工作具有一定的参考学习价值