de.alpharogroup.wicket.base.util.ComponentFinder.java Source code

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Here is the source code for de.alpharogroup.wicket.base.util.ComponentFinder.java

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/**
 * Copyright (C) 2010 Asterios Raptis
 *
 * 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 de.alpharogroup.wicket.base.util;

import org.apache.wicket.Component;
import org.apache.wicket.Page;
import org.apache.wicket.ajax.AjaxRequestTarget;
import org.apache.wicket.core.request.handler.IPageRequestHandler;
import org.apache.wicket.core.request.handler.RequestSettingRequestHandler;
import org.apache.wicket.markup.html.form.Form;
import org.apache.wicket.protocol.http.WebApplication;
import org.apache.wicket.request.IRequestHandler;
import org.apache.wicket.request.cycle.RequestCycle;

import de.alpharogroup.lang.ClassExtensions;

/**
 * The Class ComponentFinder.
 */
public final class ComponentFinder {

    /**
     * Finds the AjaxRequestTarget from the current RequestCycle.
     *
     * @return the found AjaxRequestTarget or {@code null}
     */
    public static AjaxRequestTarget findAjaxRequestTarget() {
        return RequestCycle.get().find(AjaxRequestTarget.class);
    }

    /**
     * Finds the current {@link AjaxRequestTarget} or creates a new ajax request target from the
     * given application and page if the current {@link AjaxRequestTarget} is null.
     *
     * @return an AjaxRequestTarget instance
     *
     * @see WebApplication#newAjaxRequestTarget(Page)
     */
    public static AjaxRequestTarget findOrCreateNewAjaxRequestTarget() {
        return findOrCreateNewAjaxRequestTarget(WebApplication.get(), getCurrentPage());
    }

    /**
     * Finds the current {@link AjaxRequestTarget} or creates a new ajax request target from the
     * given application and page if the current {@link AjaxRequestTarget} is null.
     *
     * @param application
     *            the web application
     * @param page
     *            page on which ajax response is made
     * @return an AjaxRequestTarget instance
     *
     * @see WebApplication#newAjaxRequestTarget(Page)
     */
    public static AjaxRequestTarget findOrCreateNewAjaxRequestTarget(final WebApplication application,
            final Page page) {
        final AjaxRequestTarget target = findAjaxRequestTarget();
        if (target != null) {
            return target;
        }
        return newAjaxRequestTarget(application, page);
    }

    /**
     * Finds the first parent of the given childComponent from the given parentClass.
     *
     * @param childComponent
     *            the child component
     * @param parentClass
     *            the parent class
     * @return the component
     */
    public static Component findParent(final Component childComponent,
            final Class<? extends Component> parentClass) {
        return findParent(childComponent, parentClass, true);
    }

    /**
     * Finds the first parent of the given childComponent from the given parentClass and a flag if
     * the search shell be continued with the class name if the search with the given parentClass
     * returns null.
     *
     * @param childComponent
     *            the child component
     * @param parentClass
     *            the parent class
     * @param byClassname
     *            the flag to search by classname if the search with given parentClass returns null.
     * @return the component
     */
    public static Component findParent(final Component childComponent, final Class<? extends Component> parentClass,
            final boolean byClassname) {
        Component parent = childComponent.getParent();
        while (parent != null) {
            if (parent.getClass().equals(parentClass)) {
                break;
            }
            parent = parent.getParent();
        }
        if ((parent == null) && byClassname) {
            return findParentByClassname(childComponent, parentClass);
        }
        return parent;
    }

    /**
     * Finds the first parent of the given childComponent from the given parentClass.
     *
     * @param childComponent
     *            the child component
     * @param parentClass
     *            the parent class
     * @return the component
     */
    public static Component findParentByClassname(final Component childComponent,
            final Class<? extends Component> parentClass) {
        Component parent = childComponent.getParent();
        while (parent != null) {
            if (ClassExtensions.equalsByClassName(parentClass, parent.getClass())) {
                break;
            }
            parent = parent.getParent();
        }
        return parent;
    }

    /**
     * Finds the parent form of the given childComponent.
     *
     * @param childComponent
     *            the child component
     * @return the component or null if no form is found.
     */
    public static Component findParentForm(final Component childComponent) {
        final Component parent = findParent(childComponent, Form.class);
        if ((parent != null) && parent.getClass().equals(Form.class)) {
            return parent;
        }
        return null;
    }

    /**
     * Gets the current page.
     *
     * @return the current page
     */
    public static Page getCurrentPage() {
        final IRequestHandler requestHandler = RequestCycle.get().getActiveRequestHandler();
        final Page page = getPage(requestHandler);
        if (page != null) {
            return page;
        }
        if (requestHandler instanceof RequestSettingRequestHandler) {
            final RequestSettingRequestHandler requestSettingRequestHandler = (RequestSettingRequestHandler) requestHandler;
            return getPage(requestSettingRequestHandler.getDelegateHandler());
        }
        return null;
    }

    /**
     * Gets the page if the request handler is instance of IPageRequestHandler.
     *
     * @param requestHandler
     *            The {@link IRequestHandler} to get the page.
     * @return The page or null if not found.
     */
    public static Page getPage(final IRequestHandler requestHandler) {
        if (requestHandler instanceof IPageRequestHandler) {
            final IPageRequestHandler pageRequestHandler = (IPageRequestHandler) requestHandler;
            return (Page) pageRequestHandler.getPage();
        }
        return null;
    }

    /**
     * Creates a new ajax request target from the given Page.
     *
     * @param application
     *            the web application
     * @param page
     *            page on which ajax response is made
     * @return an AjaxRequestTarget instance
     *
     * @see WebApplication#newAjaxRequestTarget(Page)
     *
     */
    @SuppressWarnings("javadoc")
    public static AjaxRequestTarget newAjaxRequestTarget(final WebApplication application, final Page page) {
        return application.newAjaxRequestTarget(page);
    }
}