The specification of MethodHandles.constant(Class<?> type, Object value) makes the following statement:

The returned method handle is equivalent to identity(type).bindTo(value).

However, this is wrong for "type" representing a primitive type, as MethodHandle#bindTo(...) throws (as specified) an IllegalArgumentException if the leading parameter type is not a reference type.

I see three ways to fix the specification here:

1. Remove the sentence mentioning bindTo.
2. Replace the sentence and mention MethodHandles.insertArguments(...) instead.
3. Change the sentence to mention that this equivalence is only true for reference types.

I would personally go with 2.