String equality comparison with == operator

What went wrong: In Java, the == operator compares object reference identities (memory addresses), not the actual character contents of the strings. Strings constructed at runtime or dynamically are distinct objects, so == evaluates to false.

The fix: Use "admin".equals(role) to perform content comparison, which also protects against null pointer exceptions if role is null.

Remember: Always compare Strings in Java using .equals(), never ==. Put the string literal first ("admin".equals(role)) to avoid NullPointerException.