@Override
	@SuppressWarnings("unchecked")
	public boolean shouldTrigger(String dslStart, Exception exception, CompletionKind kind) {
		if (!exceptionClass.isAssignableFrom(exception.getClass())) {
			return false;
		}
		initFingerprints();
		for (List<StackTraceElement> fingerPrint : fingerprints) {
			if (fingerprintMatches((E) exception, fingerPrint)) {
				return true;
			}
		}
		return false;
	}
Extract the top frames (until the call to {@link XDParser#parse(String, String)} appears) of the given exception.
spring-xd-dirt/src/main/java/org/springframework/xd/dirt/stream/completion/StacktraceFingerprintingCompletionRecoveryStrategy.java