Apparently dead code in LoggerFactory

[TWiStErRob]

While reading slf4j2 code to figure out how bindingsproviders work, I came across a line that confused me: catch(NoSuchFieldError) in LoggerFactory

slf4j/slf4j-api/src/main/java/org/slf4j/LoggerFactory.java

Lines 364 to 388 in 216459e

	private final static void versionSanityCheck() {
	try {
	String requested = PROVIDER.getRequestedApiVersion();
	boolean match = false;
	for (String aAPI_COMPATIBILITY_LIST : API_COMPATIBILITY_LIST) {
	if (requested.startsWith(aAPI_COMPATIBILITY_LIST)) {
	match = true;
	}
	}
	if (!match) {
	Util.report("The requested version " + requested + " by your slf4j provider is not compatible with "
	+ Arrays.asList(API_COMPATIBILITY_LIST).toString());
	Util.report("See " + VERSION_MISMATCH + " for further details.");
	}
	} catch (java.lang.NoSuchFieldError nsfe) {
	// given our large user base and SLF4J's commitment to backward
	// compatibility, we cannot cry here. Only for implementations
	// which willingly declare a REQUESTED_API_VERSION field do we
	// emit compatibility warnings.
	} catch (Throwable e) {
	// we should never reach here
	Util.report("Unexpected problem occurred during version sanity check", e);
	}
	}

I was wondering why the comment references REQUESTED_API_VERSION, while there's no such thing in the try.

I found the change that invalidated that catch, and I'm still baffled as to why Java does not complain about a checked exception being not used I see why javac didn't alert: it's an Error, not checked!.

[ceki]

Hi @TWiStErRob

I think the NoSuchFieldError can no longer occur and it makes no sense to check for it. As for the compiler not complaining, it is a good question but beyond the scope of SLF4J. ☺️

[TWiStErRob]

See edit: Error is not a checked exception.

[ceki]

Unreachable code removed in commit 5ccbe20