private void initDragNDrop() {

		acceptableFlavors = getAcceptableDataFlavors();

		// set up drop stuff
		dropTargetAdapter =
			new DropTgtAdapter(this, DnDConstants.ACTION_COPY_OR_MOVE, acceptableFlavors);
		dropTarget =
			new DropTarget(this, DnDConstants.ACTION_COPY_OR_MOVE, dropTargetAdapter, true);
		dropTarget.setActive(true);

		// set up drag stuff
		dragSource = DragSource.getDefaultDragSource();
		dragGestureAdapter = new DragGestureAdapter(this);
		dragSourceAdapter = new TreeDragSrcAdapter(this);
		dragSource.createDefaultDragGestureRecognizer(this, dragAction, dragGestureAdapter);
	}
Set up the drag and drop stuff.
Ghidra/Features/Base/src/main/java/ghidra/app/plugin/core/programtree/DragNDropTree.java