ResourceProvider.java

/*******************************************************************************
 * Copyright (c) 2012-2017 Codenvy, S.A.
 * 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
 *
 * Contributors:
 *   Codenvy, S.A. - initial API and implementation
 *******************************************************************************/
package org.eclipse.che.ide.editor;

import com.google.inject.Inject;
import com.google.inject.Singleton;

import org.eclipse.che.api.promises.client.Function;
import org.eclipse.che.api.promises.client.Promise;
import org.eclipse.che.api.promises.client.PromiseProvider;
import org.eclipse.che.ide.api.app.AppContext;
import org.eclipse.che.ide.api.command.CommandImpl;
import org.eclipse.che.ide.api.command.CommandManager;
import org.eclipse.che.ide.api.resources.File;
import org.eclipse.che.ide.api.resources.VirtualFile;
import org.eclipse.che.ide.command.node.CommandFileNode;
import org.eclipse.che.ide.command.node.NodeFactory;

import java.util.Optional;

import static java.util.Optional.ofNullable;

/**
 * Provides resource ({@link VirtualFile}) by it's path.
 * Used internally by {@link EditorAgentImpl} for restoring opened editors.
 */
@Singleton
class ResourceProvider {

    private final AppContext      appContext;
    private final CommandManager  commandManager;
    private final NodeFactory     nodeFactory;
    private final PromiseProvider promiseProvider;

    @Inject
    public ResourceProvider(AppContext appContext,
                            CommandManager commandManager,
                            NodeFactory nodeFactory,
                            PromiseProvider promiseProvider) {
        this.appContext = appContext;
        this.commandManager = commandManager;
        this.nodeFactory = nodeFactory;
        this.promiseProvider = promiseProvider;
    }

    Promise<Optional<VirtualFile>> getResource(String path) {
        if (path.startsWith("commands/")) {
            final String commandName = path.substring(path.lastIndexOf('/') + 1);
            final Optional<CommandImpl> command = commandManager.getCommand(commandName);

            if (command.isPresent()) {
                CommandFileNode node = nodeFactory.newCommandFileNode(command.get());
                return promiseProvider.resolve(Optional.of(node));
            } else {
                return promiseProvider.reject(new Exception("Command " + commandName + " not found"));
            }
        } else {
            return appContext.getWorkspaceRoot().getFile(path)
                             .then((Function<com.google.common.base.Optional<File>, Optional<VirtualFile>>)arg -> ofNullable(arg.orNull()));
        }
    }
}