Wizard.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.api.wizard;

import javax.validation.constraints.NotNull;
import org.eclipse.che.commons.annotation.Nullable;

/**
 * The main responsibility of a {@link Wizard} subclass is doing the real work when the wizard completes.
 *
 * @param <T>
 *         the type of the data-object that stores collected data
 * @author Andrey Plotnikov
 * @author Artem Zatsarynnyi
 */
public interface Wizard<T> {
    /**
     * Performs some actions required for flipping to first page and returning to the first page of a wizard.
     *
     * @return first page
     */
    @Nullable
    WizardPage<T> navigateToFirst();

    /**
     * Provides a way to move to the next wizard page.
     *
     * @return the next page or {@code null} if wizard has no next page
     */
    @Nullable
    WizardPage<T> navigateToNext();

    /**
     * Provides a way to move to the previous wizard page.
     *
     * @return the previous page or {@code null} if wizard has no previous page
     */
    @Nullable
    WizardPage<T> navigateToPrevious();

    /**
     * Returns whether the wizard has the next page.
     *
     * @return {@code true} if the wizard has next page, otherwise - {@code false}
     */
    boolean hasNext();

    /**
     * Returns whether the wizard has previous page.
     *
     * @return {@code true} if the wizard has previous page, otherwise - {@code false}
     */
    boolean hasPrevious();

    /**
     * Checks whether the wizard may be completed.
     *
     * @return {@code true} if the wizard could be completed, otherwise - {@code false}
     */
    boolean canComplete();

    /** Complete the wizard. */
    void complete(@NotNull CompleteCallback callback);

    /** Sets update control delegate. */
    void setUpdateDelegate(@NotNull UpdateDelegate delegate);

    /** Usually it is required to enable/disable navigation buttons in wizard view. */
    interface UpdateDelegate {
        /** Called when wizard view should be updated. */
        void updateControls();
    }

    interface CompleteCallback {
        /** Called when wizard completed successfully. */
        void onCompleted();

        /** Called when failure occurred while completing wizard. */
        void onFailure(Throwable e);
    }
}