Is access checked at compile time or run time? [duplicate]

Question

Possible Duplicate:
JVM/Java, are method accessibility rules enforced at runtime?

When using a class that has both public and private fields and members, is the code checked for access violations (e.g. trying to access a private field from an outside class) at compiled time or run time? Or both?

Answer 1

Both. If you try to compile code which tries to access inaccessible object or method, you'll get compile-time error:

field has private access in package.Class

Also, when your class tries to access some field at runtime, JVM checks the access:

Exception in thread "main" java.lang.IllegalAccessError: tried to access field package.Class.field from class YourClass