ConfigDataImporter Class — spring-boot Architecture

Source Code

core/spring-boot/src/main/java/org/springframework/boot/context/config/ConfigDataImporter.java lines 42–173

class ConfigDataImporter {

	private final Log logger;

	private final ConfigDataLocationResolvers resolvers;

	private final ConfigDataLoaders loaders;

	private final ConfigDataNotFoundAction notFoundAction;

	private final Set<ConfigDataResource> loaded = new HashSet<>();

	private final Set<ConfigDataLocation> loadedLocations = new HashSet<>();

	private final Set<ConfigDataLocation> optionalLocations = new HashSet<>();

	/**
	 * Create a new {@link ConfigDataImporter} instance.
	 * @param logFactory the log factory
	 * @param notFoundAction the action to take when a location cannot be found
	 * @param resolvers the config data location resolvers
	 * @param loaders the config data loaders
	 */
	ConfigDataImporter(DeferredLogFactory logFactory, ConfigDataNotFoundAction notFoundAction,
			ConfigDataLocationResolvers resolvers, ConfigDataLoaders loaders) {
		this.logger = logFactory.getLog(getClass());
		this.resolvers = resolvers;
		this.loaders = loaders;
		this.notFoundAction = notFoundAction;
	}

	/**
	 * Resolve and load the given list of locations, filtering any that have been
	 * previously loaded.
	 * @param activationContext the activation context
	 * @param locationResolverContext the location resolver context
	 * @param loaderContext the loader context
	 * @param locations the locations to resolve
	 * @return a map of the loaded locations and data
	 */
	Map<ConfigDataResolutionResult, ConfigData> resolveAndLoad(@Nullable ConfigDataActivationContext activationContext,
			ConfigDataLocationResolverContext locationResolverContext, ConfigDataLoaderContext loaderContext,
			List<ConfigDataLocation> locations) {
		try {
			Profiles profiles = (activationContext != null) ? activationContext.getProfiles() : null;
			List<ConfigDataResolutionResult> resolved = resolve(locationResolverContext, profiles, locations);
			return load(loaderContext, resolved);
		}
		catch (IOException ex) {
			throw new IllegalStateException("IO error on loading imports from " + locations, ex);
		}
	}

	private List<ConfigDataResolutionResult> resolve(ConfigDataLocationResolverContext locationResolverContext,
			@Nullable Profiles profiles, List<ConfigDataLocation> locations) {
		List<ConfigDataResolutionResult> resolved = new ArrayList<>(locations.size());
		for (ConfigDataLocation location : locations) {
			resolved.addAll(resolve(locationResolverContext, profiles, location));
		}
		return Collections.unmodifiableList(resolved);
	}

	private List<ConfigDataResolutionResult> resolve(ConfigDataLocationResolverContext locationResolverContext,
			@Nullable Profiles profiles, ConfigDataLocation location) {
		try {
			return this.resolvers.resolve(locationResolverContext, location, profiles);
		}
		catch (ConfigDataNotFoundException ex) {
			handle(ex, location, null);
			return Collections.emptyList();
		}
	}

	private Map<ConfigDataResolutionResult, ConfigData> load(ConfigDataLoaderContext loaderContext,
			List<ConfigDataResolutionResult> candidates) throws IOException {
		Map<ConfigDataResolutionResult, ConfigData> result = new LinkedHashMap<>();
		for (int i = candidates.size() - 1; i >= 0; i--) {
			ConfigDataResolutionResult candidate = candidates.get(i);
			ConfigDataLocation location = candidate.getLocation();
			ConfigDataResource resource = candidate.getResource();
			this.logger.trace(LogMessage.format("Considering resource %s from location %s", resource, location));
			if (resource.isOptional()) {
				this.optionalLocations.add(location);
			}
			if (this.loaded.contains(resource)) {
				this.logger
					.trace(LogMessage.format("Already loaded resource %s ignoring location %s", resource, location));
				this.loadedLocations.add(location);
			}
			else {
				try {
					ConfigData loaded = this.loaders.load(loaderContext, resource);
					if (loaded != null) {
						this.logger.trace(LogMessage.format("Loaded resource %s from location %s", resource, location));
						this.loaded.add(resource);
						this.loadedLocations.add(location);
						result.put(candidate, loaded);
					}
				}
				catch (ConfigDataNotFoundException ex) {
					handle(ex, location, resource);
				}
			}
		}
		return Collections.unmodifiableMap(result);
	}

	private void handle(ConfigDataNotFoundException ex, ConfigDataLocation location,
			@Nullable ConfigDataResource resource) {
		if (ex instanceof ConfigDataResourceNotFoundException notFoundException) {
			ex = notFoundException.withLocation(location);
		}
		getNotFoundAction(location, resource).handle(this.logger, ex);
	}

	private ConfigDataNotFoundAction getNotFoundAction(ConfigDataLocation location,
			@Nullable ConfigDataResource resource) {
		if (location.isOptional() || (resource != null && resource.isOptional())) {
			return ConfigDataNotFoundAction.IGNORE;
		}
		return this.notFoundAction;
	}

	Set<ConfigDataLocation> getLoadedLocations() {
		return this.loadedLocations;
	}

	Set<ConfigDataLocation> getOptionalLocations() {
		return this.optionalLocations;
	}

}