import org.aspectj.lang.annotation.*; public aspect AtAspectJDeclareParents { @DeclareParents(value="C",defaultImpl=Impl.class) private I implementedInterface; } class C {} interface I{ int getX(); void setX(int x); } class Impl implements I { public Impl() {} private int x; public int getX() { return this.x; } public void setX(int x) { this.x = x; } }