ConfigurationClassFilter Class — spring-boot Architecture

Source Code

core/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/AutoConfigurationImportSelector.java lines 388–429

	private static class ConfigurationClassFilter {

		private final AutoConfigurationMetadata autoConfigurationMetadata;

		private final List<AutoConfigurationImportFilter> filters;

		ConfigurationClassFilter(ClassLoader classLoader, List<AutoConfigurationImportFilter> filters) {
			this.autoConfigurationMetadata = AutoConfigurationMetadataLoader.loadMetadata(classLoader);
			this.filters = filters;
		}

		List<String> filter(List<String> configurations) {
			long startTime = System.nanoTime();
			@Nullable String[] candidates = StringUtils.toStringArray(configurations);
			boolean skipped = false;
			for (AutoConfigurationImportFilter filter : this.filters) {
				boolean[] match = filter.match(candidates, this.autoConfigurationMetadata);
				for (int i = 0; i < match.length; i++) {
					if (!match[i]) {
						candidates[i] = null;
						skipped = true;
					}
				}
			}
			if (!skipped) {
				return configurations;
			}
			List<String> result = new ArrayList<>(candidates.length);
			for (String candidate : candidates) {
				if (candidate != null) {
					result.add(candidate);
				}
			}
			if (logger.isTraceEnabled()) {
				int numberFiltered = configurations.size() - result.size();
				logger.trace("Filtered " + numberFiltered + " auto configuration class in "
						+ TimeUnit.NANOSECONDS.toMillis(System.nanoTime() - startTime) + " ms");
			}
			return result;
		}

	}