text: public virtual void remove(){if (this._enclosing.modCount != this.expectedModCount){throw new java.util.ConcurrentModificationException();}if (this.lastReturned == null){throw new System.InvalidOperationException();}this._enclosing.remove(this.lastReturned.key);this.lastReturned = null;this.expectedModCount = this._enclosing.modCount;}