Java tutorial
/* * Licensed to the Apache Software Foundation (ASF) under one or more * contributor license agreements. See the NOTICE file distributed with * this work for additional information regarding copyright ownership. * The ASF licenses this file to You 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.apache.wicket.ajax.form; import org.apache.wicket.Component; import org.apache.wicket.ajax.AjaxEventBehavior; import org.apache.wicket.ajax.AjaxRequestTarget; import org.apache.wicket.ajax.attributes.AjaxRequestAttributes; import org.apache.wicket.ajax.attributes.AjaxRequestAttributes.Method; import org.apache.wicket.markup.html.form.Button; import org.apache.wicket.markup.html.form.Form; import org.apache.wicket.markup.html.form.IFormSubmitter; import org.apache.wicket.markup.html.form.IFormSubmittingComponent; import org.apache.wicket.util.lang.Args; import org.danekja.java.util.function.serializable.SerializableConsumer; /** * Ajax event behavior that submits a form via ajax when the event it is attached to, is invoked. * <p> * The form must have an id attribute in the markup or have MarkupIdSetter added. * * @see AjaxEventBehavior * * @since 1.2 * * @author Igor Vaynberg (ivaynberg) * @see #onSubmit(org.apache.wicket.ajax.AjaxRequestTarget) * @see #onAfterSubmit(org.apache.wicket.ajax.AjaxRequestTarget) * @see #onError(org.apache.wicket.ajax.AjaxRequestTarget) */ public abstract class AjaxFormSubmitBehavior extends AjaxEventBehavior { private static final long serialVersionUID = 1L; /** * should never be accessed directly (thus the __ cause its overkill to create a super class), * instead always use #getForm() */ private Form<?> __form; private boolean defaultProcessing = true; /** * Constructor. This constructor can only be used when the component this behavior is attached * to is inside a form. * * @param event * javascript event this behavior is attached to, like onclick */ public AjaxFormSubmitBehavior(String event) { this(null, event); } /** * Construct. * * @param form * form that will be submitted * @param event * javascript event this behavior is attached to, like onclick */ public AjaxFormSubmitBehavior(Form<?> form, String event) { super(event); __form = form; if (form != null) { form.setOutputMarkupId(true); } } /** * @return Form that will be submitted by this behavior */ public final Form<?> getForm() { if (__form == null) { __form = findForm(); if (__form == null) { throw new IllegalStateException("form was not specified in the constructor and cannot " + "be found in the hierarchy of the component this behavior " + "is attached to: Component=" + getComponent().toString(false)); } } return __form; } /** * @return the bound component if it implements {@link org.apache.wicket.markup.html.form.IFormSubmittingComponent}, * otherwise - {@code null} */ private IFormSubmittingComponent getFormSubmittingComponent() { IFormSubmittingComponent submittingComponent = null; Component component = getComponent(); if (component instanceof IFormSubmittingComponent) { submittingComponent = ((IFormSubmittingComponent) component); } return submittingComponent; } /** * Finds form that will be submitted * * @return form to submit or {@code null} if none found */ protected Form<?> findForm() { // try to find form in the hierarchy of owning component Component component = getComponent(); if (component instanceof Form<?>) { return (Form<?>) component; } else { return component.findParent(Form.class); } } @Override protected void updateAjaxAttributes(AjaxRequestAttributes attributes) { super.updateAjaxAttributes(attributes); Form<?> form = getForm(); attributes.setFormId(form.getMarkupId()); String formMethod = form.getMarkupAttributes().getString("method"); if (formMethod == null || "POST".equalsIgnoreCase(formMethod)) { attributes.setMethod(Method.POST); } if (form.getRootForm().isMultiPart()) { attributes.setMultipart(true); attributes.setMethod(Method.POST); } IFormSubmittingComponent submittingComponent = getFormSubmittingComponent(); if (submittingComponent != null) { String submittingComponentName = submittingComponent.getInputName(); attributes.setSubmittingComponentName(submittingComponentName); } } @Override protected void onEvent(final AjaxRequestTarget target) { AjaxFormSubmitBehavior.AjaxFormSubmitter submitter = new AjaxFormSubmitBehavior.AjaxFormSubmitter(this, target); Form<?> form = getForm(); form.getRootForm().onFormSubmitted(submitter); } /** * A publicly reachable class that allows to introspect the submitter, e.g. to * check what is the input name of the submitting component if there is such. */ public static class AjaxFormSubmitter implements IFormSubmitter { private final AjaxFormSubmitBehavior submitBehavior; private final AjaxRequestTarget target; private AjaxFormSubmitter(AjaxFormSubmitBehavior submitBehavior, AjaxRequestTarget target) { this.submitBehavior = submitBehavior; this.target = target; } @Override public Form<?> getForm() { return submitBehavior.getForm(); } /** * @return the {@link IFormSubmittingComponent} */ public IFormSubmittingComponent getFormSubmittingComponent() { return submitBehavior.getFormSubmittingComponent(); } @Override public boolean getDefaultFormProcessing() { return submitBehavior.getDefaultProcessing(); } @Override public void onError() { submitBehavior.onError(target); } @Override public void onSubmit() { submitBehavior.onSubmit(target); } @Override public void onAfterSubmit() { submitBehavior.onAfterSubmit(target); } } /** * Override this method to provide special submit handling in a multi-button form. This method * will be called <em>after</em> the form's onSubmit method. * @param target the {@link AjaxRequestTarget} */ protected void onAfterSubmit(AjaxRequestTarget target) { } /** * Override this method to provide special submit handling in a multi-button form. This method * will be called <em>before</em> the form's onSubmit method. * @param target the {@link AjaxRequestTarget} */ protected void onSubmit(AjaxRequestTarget target) { } /** * Listener method invoked when the form has been processed and errors occurred * * @param target */ protected void onError(AjaxRequestTarget target) { } /** * @see Button#getDefaultFormProcessing() * * @return {@code true} for default processing */ public boolean getDefaultProcessing() { return defaultProcessing; } /** * @see Button#setDefaultFormProcessing(boolean) * @param defaultProcessing */ public void setDefaultProcessing(boolean defaultProcessing) { this.defaultProcessing = defaultProcessing; } /** * Creates an {@link AjaxFormSubmitBehavior} based on lambda expressions * * @param eventName * the event name * @param onSubmit * the {@code SerializableConsumer} which accepts the {@link AjaxRequestTarget} * @return the {@link AjaxFormSubmitBehavior} */ public static AjaxFormSubmitBehavior onSubmit(String eventName, SerializableConsumer<AjaxRequestTarget> onSubmit) { Args.notNull(onSubmit, "onSubmit"); return new AjaxFormSubmitBehavior(eventName) { private static final long serialVersionUID = 1L; @Override protected void onSubmit(AjaxRequestTarget target) { onSubmit.accept(target); } }; } }