AbstractDiagramPreview.java

/*
 * Copyright 2017 Red Hat, Inc. and/or its affiliates.
 *
 * Licensed 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
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.kie.workbench.common.stunner.client.widgets.presenters.diagram.impl;

import org.kie.workbench.common.stunner.client.widgets.presenters.diagram.DiagramViewer;
import org.kie.workbench.common.stunner.client.widgets.views.WidgetWrapperView;
import org.kie.workbench.common.stunner.core.client.canvas.AbstractCanvasHandler;
import org.kie.workbench.common.stunner.core.diagram.Diagram;
import org.uberfire.mvp.Command;

public abstract class AbstractDiagramPreview<D extends Diagram, H extends AbstractCanvasHandler>
        implements DiagramViewer<D, H> {

    protected abstract int getWidth();

    protected abstract int getHeight();

    public abstract AbstractDiagramViewer<D, H> getViewer();

    @Override
    public void open(final D item,
                     final DiagramViewerCallback<D> callback) {
        getViewerOrNothing(() -> getViewer().open(item,
                                                  getWidth(),
                                                  getHeight(),
                                                  true,
                                                  callback));
    }

    @Override
    public void open(final D item,
                     final int width,
                     final int height,
                     final DiagramViewerCallback<D> callback) {
        getViewerOrNothing(() -> getViewer().open(item,
                                                  width,
                                                  height,
                                                  true,
                                                  callback));
    }

    @Override
    public void scale(final int width,
                      final int height) {
        getViewerOrNothing(() -> getViewer().scale(width,
                                                   height,
                                                   true));
    }

    @Override
    public void clear() {
        getViewerOrNothing(() -> getViewer().clear());
    }

    @Override
    public void destroy() {
        getViewerOrNothing(() -> getViewer().destroy());
    }

    @Override
    public D getInstance() {
        return null != getViewer() ? getViewer().getInstance() : null;
    }

    @Override
    public H getHandler() {
        return null != getViewer() ? getViewer().getHandler() : null;
    }

    @Override
    public WidgetWrapperView getView() {
        return getViewer().getView();
    }

    private void getViewerOrNothing(final Command callback) {
        if (null != getViewer()) {
            callback.execute();
        }
    }
}