Catching an exception and throwing another is a common pattern. This is often used to supply additional information, or to turn a checked exception into an unchecked one.
try { ioLogic(); } catch (IOException e) { throw new IllegalStateException(); // BAD }
Throwing a new exception without supplying the caught one as a cause means the stack trace will terminate at the catch block, which will make debugging a possible fault in ioLogic() far harder than is necessary.
Prefer wrapping the original exception instead,
try { ioLogic(); } catch (IOException e) { throw new IllegalStateException(e); // GOOD }
If the exception is deliberately unused, rename it _ or unused to suppress this diagnostic.
static <T extends Enum<T>> T tryForName(Class<T> enumType, String name) { try { return Enum.valueOf(enumType, name); } catch (IllegalArgumentException unused) { return null; } }
Otherwise, suppress false positives with @SuppressWarnings("UnusedException") on the ignored exception. Consider also adding a comment to explain why the exception should not be propagated.
try { ... } catch (@SuppressWarnings("UnusedException") IOException e) { throw new IllegalStateException(); }