ViewContentProvider.java

/**
 * Copyright (c) 2014-2017 by the respective copyright holders.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 */
package org.eclipse.smarthome.designer.ui.internal.views;

import java.util.ArrayList;
import java.util.List;

import org.eclipse.core.resources.IFolder;
import org.eclipse.core.resources.IProject;
import org.eclipse.core.resources.IResource;
import org.eclipse.core.runtime.CoreException;
import org.eclipse.jface.viewers.IStructuredContentProvider;
import org.eclipse.jface.viewers.ITreeContentProvider;
import org.eclipse.jface.viewers.Viewer;
import org.eclipse.smarthome.designer.core.config.ConfigurationFolderProvider;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

/**
 * The content provider class is responsible for
 * providing objects to the view. It can wrap
 * existing objects in adapters or simply return
 * objects as-is. These objects may be sensitive
 * to the current input of the view, or ignore
 * it and always show the same content
 *
 * @author Kai Kreuzer - Initial contribution and API
 *
 */
public class ViewContentProvider implements IStructuredContentProvider, ITreeContentProvider {

    private final Logger logger = LoggerFactory.getLogger(ViewContentProvider.class);

    private IFolder configRootFolder;

    @Override
    public void inputChanged(Viewer v, Object oldInput, Object newInput) {
        if (newInput instanceof IFolder) {
            configRootFolder = (IFolder) newInput;
        }
    }

    @Override
    public void dispose() {
        configRootFolder = null;
    }

    @Override
    public Object[] getElements(Object parent) {
        if (parent instanceof IProject) {
            try {
                configRootFolder = ConfigurationFolderProvider.getRootConfigurationFolder();
                if (configRootFolder != null) {
                    return getChildren(configRootFolder);
                } else {
                    return new String[] { "<select a configuration folder>" };
                }
            } catch (CoreException e) {
                logger.error("Cannot initialize configuration project in workspace", e);
                return new Object[0];
            }
        }
        return getChildren(parent);
    }

    @Override
    public Object getParent(Object child) {
        if (child.equals(configRootFolder))
            return null;

        if (child instanceof IResource) {
            IResource res = (IResource) child;
            return res.getParent();
        }
        return null;
    }

    @Override
    public Object[] getChildren(Object parent) {
        if (parent instanceof IFolder) {
            IFolder folder = (IFolder) parent;
            try {
                IResource[] resources = folder.members();
                List<IResource> children = new ArrayList<IResource>(resources.length);
                for (IResource child : resources) {
                    // filter out hidden files
                    if (!child.getName().startsWith(".")) {
                        children.add(child);
                    }
                }
                return children.toArray(new IResource[children.size()]);
            } catch (CoreException e) {
                logger.warn("Error getting children for folder '{}'", folder.getName(), e);
            }
        }
        return new Object[0];
    }

    @Override
    public boolean hasChildren(Object parent) {
        return getChildren(parent).length > 0;
    }
}