private String check(String candidate, Pattern regex) {
		if (!regex.matcher(candidate).matches()) {
			throw new IllegalArgumentException("'" + candidate + "' should match " + regex);
		}
		return candidate;
	}
A mapping from class to Title in the doc. Insertion order will become rendering order.
documentation-toolchain/src/test/java/org/springframework/xd/documentation/ShellReferenceDoc.java