private static String parseStringValue()

in spring-boot-project/spring-boot-tools/spring-boot-loader/src/main/java/org/springframework/boot/loader/util/SystemPropertyUtils.java [91:142]

42 lines of code
8 McCabe index (conditional complexity)


	private static String parseStringValue(Properties properties, String value, String current,
			Set<String> visitedPlaceholders) {

		StringBuilder buf = new StringBuilder(current);

		int startIndex = current.indexOf(PLACEHOLDER_PREFIX);
		while (startIndex != -1) {
			int endIndex = findPlaceholderEndIndex(buf, startIndex);
			if (endIndex != -1) {
				String placeholder = buf.substring(startIndex + PLACEHOLDER_PREFIX.length(), endIndex);
				String originalPlaceholder = placeholder;
				if (!visitedPlaceholders.add(originalPlaceholder)) {
					throw new IllegalArgumentException(
							"Circular placeholder reference '" + originalPlaceholder + "' in property definitions");
				}
				// Recursive invocation, parsing placeholders contained in the
				// placeholder
				// key.
				placeholder = parseStringValue(properties, value, placeholder, visitedPlaceholders);
				// Now obtain the value for the fully resolved key...
				String propVal = resolvePlaceholder(properties, value, placeholder);
				if (propVal == null) {
					int separatorIndex = placeholder.indexOf(VALUE_SEPARATOR);
					if (separatorIndex != -1) {
						String actualPlaceholder = placeholder.substring(0, separatorIndex);
						String defaultValue = placeholder.substring(separatorIndex + VALUE_SEPARATOR.length());
						propVal = resolvePlaceholder(properties, value, actualPlaceholder);
						if (propVal == null) {
							propVal = defaultValue;
						}
					}
				}
				if (propVal != null) {
					// Recursive invocation, parsing placeholders contained in the
					// previously resolved placeholder value.
					propVal = parseStringValue(properties, value, propVal, visitedPlaceholders);
					buf.replace(startIndex, endIndex + PLACEHOLDER_SUFFIX.length(), propVal);
					startIndex = buf.indexOf(PLACEHOLDER_PREFIX, startIndex + propVal.length());
				}
				else {
					// Proceed with unprocessed value.
					startIndex = buf.indexOf(PLACEHOLDER_PREFIX, endIndex + PLACEHOLDER_SUFFIX.length());
				}
				visitedPlaceholders.remove(originalPlaceholder);
			}
			else {
				startIndex = -1;
			}
		}

		return buf.toString();
	}