/*
 * Copyright (c) 2009-2020 jMonkeyEngine
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are
 * met:
 *
 * * Redistributions of source code must retain the above copyright
 *   notice, this list of conditions and the following disclaimer.
 *
 * * Redistributions in binary form must reproduce the above copyright
 *   notice, this list of conditions and the following disclaimer in the
 *   documentation and/or other materials provided with the distribution.
 *
 * * Neither the name of 'jMonkeyEngine' nor the names of its contributors
 *   may be used to endorse or promote products derived from this software
 *   without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */
package com.jme3.gde.core.assets;

import com.jme3.gde.core.assets.nodes.ProjectAssetsNode;
import org.netbeans.api.project.Project;
import org.netbeans.spi.project.ui.support.NodeFactory;
import org.netbeans.spi.project.ui.support.NodeFactorySupport;
import org.netbeans.spi.project.ui.support.NodeList;
import org.openide.loaders.DataObject;
import org.openide.loaders.DataObjectNotFoundException;
import org.openide.nodes.Node;
import org.openide.util.Exceptions;

/**
 * This Factory creates the visual "Project Assets" Node in the Project View
 * @author normenhansen
 */
@SuppressWarnings({"unchecked", "rawtypes"})
public class ProjectAssetsNodeFactory implements NodeFactory {
    private Project proj;

    // return a new node for the project view if theres an assets folder
    @Override
    public NodeList createNodes(Project project) {
        this.proj = project;

        try {
            ProjectAssetManager item = project.getLookup().lookup(ProjectAssetManager.class);
            if (item != null) {
                DataObject assetsFolder = DataObject.find(item.getAssetFolder());
                ProjectAssetsNode nd = new ProjectAssetsNode(item, proj, assetsFolder.getNodeDelegate());
                return NodeFactorySupport.fixedNodeList(nd);
            }
        } catch (DataObjectNotFoundException ex) {
            Exceptions.printStackTrace(ex);
        }

        /* If our item isn't in the lookup, which means it is no recognized project
         * then return an empty list of nodes.
         */
        return NodeFactorySupport.fixedNodeList();
    }
}

/*
 * Copyright (c) 2009-2020 jMonkeyEngine
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are
 * met:
 *
 * * Redistributions of source code must retain the above copyright
 *   notice, this list of conditions and the following disclaimer.
 *
 * * Redistributions in binary form must reproduce the above copyright
 *   notice, this list of conditions and the following disclaimer in the
 *   documentation and/or other materials provided with the distribution.
 *
 * * Neither the name of 'jMonkeyEngine' nor the names of its contributors
 *   may be used to endorse or promote products derived from this software
 *   without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */
package com.jme3.gde.core.assets;

import com.jme3.gde.core.assets.nodes.ProjectAssetsNode;
import org.netbeans.api.project.Project;
import org.netbeans.spi.project.ui.support.NodeFactory;
import org.netbeans.spi.project.ui.support.NodeFactorySupport;
import org.netbeans.spi.project.ui.support.NodeList;
import org.openide.loaders.DataObject;
import org.openide.loaders.DataObjectNotFoundException;
import org.openide.util.Exceptions;

/**
 * This Factory creates the visual "Project Assets" Node in the Project View
 * @author normenhansen
 */
@SuppressWarnings({"unchecked", "rawtypes"})
public class ProjectAssetsNodeFactory implements NodeFactory {
    private Project proj;

    // return a new node for the project view if theres an assets folder
    @Override
    public NodeList createNodes(Project project) {
        this.proj = project;

        try {
            ProjectAssetManager item = project.getLookup().lookup(ProjectAssetManager.class);
            if (item != null) {
                DataObject assetsFolder = DataObject.find(item.getAssetFolder());
                ProjectAssetsNode nd = new ProjectAssetsNode(item, proj, assetsFolder.getNodeDelegate());
                return NodeFactorySupport.fixedNodeList(nd);
            }
        } catch (DataObjectNotFoundException ex) {
            Exceptions.printStackTrace(ex);
        }

        /* If our item isn't in the lookup, which means it is no recognized project
         * then return an empty list of nodes.
         */
        return NodeFactorySupport.fixedNodeList();
    }
}

Remove unused import