public @interface IndexFor
For example, an expression with type @IndexFor({"a", "b"}) is non-negative and is less
than both a.length and b.length. The sequences a and b might have
different lengths.
Writing @IndexFor("arr") is equivalent to writing @NonNegative
@LTLengthOf("arr"), and that is how it is treated internally by the checker.
Thus, if you write an @IndexFor("arr") annotation, you might see warnings about
@NonNegative or @LTLengthOf.
NonNegative,
LTLengthOfpublic abstract String[] value