<li><bugzilla>54834</bugzilla> - Improve Drag & Drop in the jmeter tree</li>

import javax.swing.DropMode;

import org.apache.jmeter.gui.tree.JMeterTreeTransferHandler;

        // enable drag&drop, install a custom transfer handler

        treevar.setDragEnabled(true);

        treevar.setDropMode(DropMode.ON_OR_INSERT);

        treevar.setTransferHandler(new JMeterTreeTransferHandler());

    public boolean openJmxFilesFromDragAndDrop(Transferable tr) throws UnsupportedFlavorException, IOException {

        @SuppressWarnings("unchecked")

        List<File> files = (List<File>)

                tr.getTransferData(DataFlavor.javaFileListFlavor);

        if(files.isEmpty()) {

            return false;

        }

        File file = files.get(0);

        if(!file.getName().endsWith(".jmx")) {

            log.warn("Importing file:" + file.getName()+ "from DnD failed because file extension does not end with .jmx");

            return false;

        }

        ActionEvent fakeEvent = new ActionEvent(this, ActionEvent.ACTION_PERFORMED, ActionNames.OPEN);

        LoadDraggedFile.loadProject(fakeEvent, file);

        return true;

    }

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 * Licensed to the Apache Software Foundation (ASF) under one or more

 * contributor license agreements.  See the NOTICE file distributed with

 * this work for additional information regarding copyright ownership.

 * The ASF licenses this file to You under the Apache License, Version 2.0

 * (the "License"); you may not use this file except in compliance with

 * the License.  You may obtain a copy of the License at

 *

 *   http://www.apache.org/licenses/LICENSE-2.0

 *

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package org.apache.jmeter.gui.tree;

import java.awt.datatransfer.DataFlavor;

import java.awt.datatransfer.Transferable;

import java.awt.datatransfer.UnsupportedFlavorException;

import javax.swing.JComponent;

import javax.swing.JTree;

import javax.swing.TransferHandler;

import javax.swing.tree.TreePath;

import org.apache.jmeter.gui.GuiPackage;

import org.apache.jmeter.gui.util.MenuFactory;

import org.apache.jorphan.logging.LoggingManager;

import org.apache.log.Logger;

public class JMeterTreeTransferHandler extends TransferHandler {

    private static final long serialVersionUID = 8560957372186260765L;

    private static final Logger LOG = LoggingManager.getLoggerForClass();

    private DataFlavor nodeFlavor;

    private DataFlavor[] jMeterTreeNodeDataFlavors = new DataFlavor[1];

    public JMeterTreeTransferHandler() {

        try {

            String mimeType = DataFlavor.javaJVMLocalObjectMimeType + ";class=\"" + JMeterTreeNode[].class.getName() + "\"";

            nodeFlavor = new DataFlavor(mimeType);

            jMeterTreeNodeDataFlavors[0] = nodeFlavor;

        }

        catch (ClassNotFoundException e) {

            LOG.error("Class Not Found", e);

        }

    }

    @Override

    public int getSourceActions(JComponent c) {

        return MOVE;

    }

    @Override

    protected Transferable createTransferable(JComponent c) {

        JTree tree = (JTree) c;

        TreePath[] paths = tree.getSelectionPaths();

        if (paths != null) {

            //TODO : deal with all the selected nodes

            JMeterTreeNode node = (JMeterTreeNode) paths[0].getLastPathComponent();

            return new NodesTransferable(new JMeterTreeNode[] {node});

        }

        return null;

    }

    @Override

    protected void exportDone(JComponent source, Transferable data, int action) {

    }

    @Override

    public boolean canImport(TransferHandler.TransferSupport support) {

        if (!support.isDrop()) {

            return false;

        }

        // the tree accepts a jmx file 

        DataFlavor[] flavors = support.getDataFlavors();

        for (int i = 0; i < flavors.length; i++) {

            // Check for file lists specifically

            if (flavors[i].isFlavorJavaFileListType()) {

                return true;

            }

        }

        // or a treenode from the same tree

        if (!support.isDataFlavorSupported(nodeFlavor)) {

            return false;

        }

        // the copy is disabled

        int action = support.getDropAction();

        if(action != MOVE) {

            return false;

        }

        support.setShowDropLocation(true);

        // Do not allow a drop on the drag source selections.

        JTree.DropLocation dl = (JTree.DropLocation) support.getDropLocation();

        JTree tree = (JTree) support.getComponent();

        int dropRow = tree.getRowForPath(dl.getPath());

        int[] selRows = tree.getSelectionRows();

        for (int i = 0; i < selRows.length; i++) {

            if (selRows[i] == dropRow) {

                return false;

            }

        }

        TreePath dest = dl.getPath();

        JMeterTreeNode target = (JMeterTreeNode) dest.getLastPathComponent();

        // TestPlan and WorkBench are the only children of the root

        if(target.isRoot()) {

            return false;

        }

        TreePath path = tree.getPathForRow(selRows[0]);

        JMeterTreeNode draggedNode = (JMeterTreeNode) path.getLastPathComponent();

        // Do not allow a non-leaf node to be moved into one of its children

        if (draggedNode.getChildCount() > 0

                && target.isNodeAncestor(draggedNode)) {

            return false;

        }

        // re-use node association logic

        return MenuFactory.canAddTo(target, new JMeterTreeNode[] { draggedNode });

    }

    @Override

    public boolean importData(TransferHandler.TransferSupport support) {

        if (!canImport(support)) {

            return false;

        }

        // deal with the jmx files

        GuiPackage guiInstance = GuiPackage.getInstance();

        DataFlavor[] flavors = support.getDataFlavors();

        Transferable t = support.getTransferable();

        for (int i = 0; i < flavors.length; i++) {

            // Check for file lists specifically

            if (flavors[i].isFlavorJavaFileListType()) {

                try {

                    return guiInstance.getMainFrame().openJmxFilesFromDragAndDrop(t);

                }

                catch (Exception e) {

                    LOG.error("Drop file failed", e);

                }

                return false;

            }

        }

        // Extract transfer data.

        JMeterTreeNode[] nodes = null;

        try {

            nodes = (JMeterTreeNode[]) t.getTransferData(nodeFlavor);

        }

        catch (Exception e) {

            LOG.error("Unsupported Flavor in Transferable", e);

        }

        if(nodes == null || nodes.length == 0) {

            return false;

        }

        // Get drop location and mode

        JTree.DropLocation dl = (JTree.DropLocation) support.getDropLocation();

        TreePath dest = dl.getPath();

        JMeterTreeNode parent = (JMeterTreeNode) dest.getLastPathComponent();

        //TODO : deal with all the selected nodes

        JMeterTreeNode draggedNode = nodes[0];

        int index = dl.getChildIndex();

        if (index == -1) { // drop mode is ON

            // can not drop in the current parent

            if(draggedNode.getParent() == parent) {

                return false;

            }

            index = parent.getChildCount();

        }

        else if(draggedNode.getParent() == parent) { // insert mode

            if(guiInstance.getTreeModel().getIndexOfChild(parent, draggedNode) < index) {

                index--;

            }

        }

        // remove - add the nodes

        for (int i = 0; i < nodes.length; i++) {

            guiInstance.getTreeModel().removeNodeFromParent(nodes[i]);

            guiInstance.getTreeModel().insertNodeInto(nodes[i], parent, index);

        }

        // expand the destination node

        JTree tree = (JTree) support.getComponent();

        tree.expandPath(new TreePath(parent.getPath()));

        return true;

    }

    private class NodesTransferable implements Transferable {

        JMeterTreeNode[] nodes;

        public NodesTransferable(JMeterTreeNode[] nodes) {

            this.nodes = nodes;

        }

        @Override

        public Object getTransferData(DataFlavor flavor) throws UnsupportedFlavorException {

            if (!isDataFlavorSupported(flavor)) {

                throw new UnsupportedFlavorException(flavor);

            }

            return nodes;

        }

        @Override

        public DataFlavor[] getTransferDataFlavors() {

            return jMeterTreeNodeDataFlavors;

        }

        @Override

        public boolean isDataFlavorSupported(DataFlavor flavor) {

            return nodeFlavor.equals(flavor);

        }

    }

}