Java in a Nutshell, 5th Edition

Name

GuardedObject

Synopsis

This class uses a Guard object to guard against unauthorized access to an arbitrary encapsulated object. Create a GuardedObject by specifying an object and a Guard for it. The getObject( ) method calls the checkGuard( ) method of the Guard to determine whether access to the object should be allowed. If access is allowed, getObject( ) returns the encapsulated object. Otherwise, it throws a java.lang.SecurityException.

The Guard object used by a GuardedObject is often a Permission. In this case, access to the guarded object is granted only if the calling code is granted the specified permission by the current security policy.

Figure 14-11. java.security.GuardedObject

public class GuardedObject implements Serializable {
// Public Constructors
     public GuardedObject(Object object, Guard guard);  
// Public Instance Methods
     public Object getObject( ) throws SecurityException;  
}