com.java33.vizpres.client.AppController.java Source code

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Here is the source code for com.java33.vizpres.client.AppController.java

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/*
 * Copyright (c) 2011 Jon Buffington. All rights reserved.
 *
 * 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 com.java33.vizpres.client;

import com.google.gwt.core.client.GWT;
import com.google.gwt.event.logical.shared.ValueChangeEvent;
import com.google.gwt.event.logical.shared.ValueChangeHandler;
import com.google.gwt.event.shared.EventBus;
import com.google.gwt.user.client.History;
import com.google.gwt.user.client.ui.HasWidgets;
import com.google.inject.Inject;
import com.java33.vizpres.client.event.DataEvent;
import com.java33.vizpres.client.gin.AppInjector;
import com.java33.vizpres.client.presenter.Presenter;
import com.java33.vizpres.client.view.visualization.IsDataSync;
import com.java33.vizpres.shared.service.PercentServiceAsync;
import com.java33.vizpres.shared.model.PercentValue;
import org.fusesource.restygwt.client.Method;
import org.fusesource.restygwt.client.MethodCallback;
import org.fusesource.restygwt.client.Resource;
import org.fusesource.restygwt.client.RestServiceProxy;

import java.util.List;
import java.util.logging.Logger;

/**
 * Coordinate the application's various presenters using GWT's History support.
 * The new Activity and Places support in GWT 2.1 would be a better choice for a
 * larger application.
 *
 * @author Jon Buffington
 */
public class AppController implements Presenter, ValueChangeHandler<String> {
    private static final Logger logger = Logger.getLogger(AppController.class.getName());

    private static final String DEFAULT_TOKEN = "default";
    private final EventBus eventBus;
    private final AppInjector injector;
    private HasWidgets container;

    @Inject
    public AppController(final EventBus eventBus, final AppInjector injector) {
        this.eventBus = eventBus;
        this.injector = injector;
        bind();
    }

    /**
     * Bind handlers to the application's events.
     */
    private void bind() {
        History.addValueChangeHandler(this);

        eventBus.addHandler(DataEvent.TYPE, new DataEvent.DataEventHandler() {
            public void onData(final DataEvent event, final IsDataSync dataSync) {
                doRequestData(dataSync);
            }
        });

    }

    /**
     * Performs the request for data and asynchronously receives the response or failure notice.
     * A response's data is pushed to the dataSync.
     *
     * @param dataSync Is the receiver of a data response's payload.
     */
    private void doRequestData(final IsDataSync dataSync) {
        final Resource resource = new Resource("/dataset");
        final PercentServiceAsync percentServiceAsync = GWT.create(PercentServiceAsync.class);
        ((RestServiceProxy) percentServiceAsync).setResource(resource);
        percentServiceAsync.getPercents(new MethodCallback<List<PercentValue>>() {
            @Override
            public void onFailure(final Method method, final Throwable throwable) {
                logger.warning(throwable.toString());
            }

            @Override
            public void onSuccess(final Method method, final List<PercentValue> values) {
                logger.fine(values.toString());
                dataSync.setData(values);
            }
        });

        //    History.newItem(EXAMPLE_TOKEN);
    }

    /**
     * Capture the desired container and pump the history value.
     */
    public void go(final HasWidgets container) {
        this.container = container;

        if ("".equals(History.getToken())) {
            History.newItem(DEFAULT_TOKEN);
        } else {
            History.fireCurrentHistoryState();
        }
    }

    /**
     * Delegate the application state handling to the appropriate target.
     */
    public void onValueChange(final ValueChangeEvent<String> event) {
        final String token = event.getValue();

        if (token != null) {
            Presenter presenter = null;

            if (token.equals(DEFAULT_TOKEN)) {
                presenter = injector.getMainPresenter();
            }

            if (presenter != null) {
                // Pass the container to the current target.
                presenter.go(container);
            }
        }
    }
}