code: protected void clear() {
  
          for (I_CmsDropTarget target : m_targets) {
              target.removePlaceholder();
          }
          if (m_dragHelper != null) {
              m_dragHelper.removeFromParent();
              m_dragHelper = null;
          }
          m_placeholder = null;
          m_currentTarget = null;
          m_draggable = null;
          Document.get().getBody().removeClassName(
              org.opencms.gwt.client.ui.css.I_CmsLayoutBundle.INSTANCE.dragdropCss().dragStarted());
          m_currentAnimation = null;
          m_modifierCTRL = false;
      }
docs: Clears all references used within the current drag process.<p>