aspectj

//TaintedObject
public interface TaintedObject {
    boolean isTainted();
    void setTainted(boolean tainted);
 }

//AbstractTaintedObjectAspect TaintedObject
public abstract aspect AbstractTaintedObjectAspect implements TaintedObject {

    public final boolean TaintedObject.isTainted() {
        return tainted;
    }
    
    public final void TaintedObject.setTainted(boolean tainted) {
        this.tainted = tainted;
    }
}

//
public aspect TaintedObjectAspect extends AbstractTaintedObjectAspect {

    declare parents: java.lang.String implements TaintedObject;
    declare parents: java.lang.StringBuffer implements TaintedObject;
    declare parents: java.lang.StringBuilder implements TaintedObject;

}

Why can String classes directly use methods implemented in abstract classes? what is the role of, declare parents here