ConfigFileApplicationListener是专门用来加载application.properties/yml或bootstrap.properties/yml配置文件的监听器。

  1. public class ConfigFileApplicationListener
  2.     implements EnvironmentPostProcessor, SmartApplicationListener, Ordered {
  4.     private static final String DEFAULT_PROPERTIES = "defaultProperties";
  6.     // Note the order is from least to most specific (last one wins)
  7.     // 顺序加载，后面的覆盖前面的
  8.     private static final String DEFAULT_SEARCH_LOCATIONS = "classpath:/,classpath:/config/,file:./,file:./config/";
  9.     // 默认加载的文件名
  10.     private static final String DEFAULT_NAMES = "application";
  11.     // 
  12.     private static final Set<String> NO_SEARCH_NAMES = Collections.singleton(null);
  13.     // 激活的profile
  14.     public static final String ACTIVE_PROFILES_PROPERTY = "spring.profiles.active";
  15.     // 
  16.     public static final String INCLUDE_PROFILES_PROPERTY = "spring.profiles.include";
  17.     // 加载的配置文件的名称，默认就是 DEFAULT_NAMES
  18.     public static final String CONFIG_NAME_PROPERTY = "spring.config.name";
  19.     // 加载位置，默认DEFAULT_SEARCH_LOCATIONS下挨个挨个去加载
  20.     public static final String CONFIG_LOCATION_PROPERTY = "spring.config.location";
  22.     /**
  23.      * The "config additional location" property name.
  24.      */
  25.     public static final String CONFIG_ADDITIONAL_LOCATION_PROPERTY = "spring.config.additional-location";
  26.     // 
  27.     public static final int DEFAULT_ORDER = Ordered.HIGHEST_PRECEDENCE + 10;
  28.     //
  29.     public static final String APPLICATION_CONFIGURATION_PROPERTY_SOURCE_NAME = "applicationConfigurationProperties";
  31.     private final DeferredLog logger = new DeferredLog();
  32.     // 搜索的路径，多个“,”隔开
  33.     private String searchLocations;
  34.     // 加载的配置文件名
  35.     private String names;
  36.     // order
  37.     private int order = DEFAULT_ORDER;
  38. }

环境准备好事件

  1. @Override
  2. public void postProcessEnvironment(ConfigurableEnvironment environment,
  3.                                    SpringApplication application) {
  4.     addPropertySources(environment, application.getResourceLoader());
  5. }
  6. protected void addPropertySources(ConfigurableEnvironment environment,
  7.                                   ResourceLoader resourceLoader) {
  8.     RandomValuePropertySource.addToEnvironment(environment);
  9.     new Loader(environment, resourceLoader).load();
  10. }

这里接收环境准备完成事件处理两件事：

  1. 添加一个处理配置中诸如random.int这样的随机数生成的RandomValuePropertySource。

  2. 加载配置文件，如bootstrap.properties，application.properties

    1. 根据阶段的不同，在执行父容器(springcloud bootstrap)时，加载的是bootstrap.properties

    2. 执行应用容器（springboot）时，加载的是application.properties ```java // 加载配置文件 public void load() { this.profiles = Collections.asLifoQueue(new LinkedList()); this.processedProfiles = new LinkedList<>(); this.activatedProfiles = false; this.loaded = new LinkedHashMap<>(); // 确定加载哪些profiles initializeProfiles(); while (!this.profiles.isEmpty()) { // 一个一个profile来 Profile profile = this.profiles.poll(); // 加载指定profile的配置文件，last load(profile, this::getPositiveProfileFilter, addToLoaded(MutablePropertySources::addLast, false)); this.processedProfiles.add(profile); }

      // 加载默认配置文件，放在first load(null, this::getNegativeProfileFilter, addToLoaded(MutablePropertySources::addFirst, true)); addLoadedPropertySources(); }

// 加载配置文件 private void load(Profile profile, DocumentFilterFactory filterFactory, DocumentConsumer consumer) { getSearchLocations().forEach((location) -> { boolean isFolder = location.endsWith(“/“); // 根据配置文件名查找 Set names = (isFolder ? getSearchNames() : NO_SEARCH_NAMES); names.forEach( (name) -> load(location, name, profile, filterFactory, consumer)); }); } // 指定的配置文件名称 private Set getSearchNames() { // 根据spring.config.name属性确定文件名 if (this.environment.containsProperty(CONFIG_NAME_PROPERTY)) { // String property = this.environment.getProperty(CONFIG_NAME_PROPERTY); return asResolvedSet(property, null); } return asResolvedSet(ConfigFileApplicationListener.this.names, DEFAULT_NAMES); } `` 默认配置时，这里加载classpath:/application-{profile}.properties/yml`等配置文件。