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/*
* Copyright OmniFaces
*
* 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
*
* https://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.omnifaces.component.input;
import static org.omnifaces.util.Messages.addFlashGlobalWarn;
import static org.omnifaces.util.Utils.isEmpty;
import java.io.IOException;
import jakarta.faces.component.FacesComponent;
import jakarta.faces.component.UIViewAction;
import jakarta.faces.context.ExternalContext;
import jakarta.faces.context.ExternalContextWrapper;
import jakarta.faces.context.FacesContext;
import jakarta.faces.context.FacesContextWrapper;
import jakarta.faces.event.ActionEvent;
import jakarta.faces.event.FacesEvent;
import org.omnifaces.util.State;
/**
*
* The <o:viewAction> is a component that extends the standard <f:viewAction> and
* changes the if attribute to be evaluated during INVOKE_APPLICATION phase instead of the
* APPLY_REQUEST_VALUES phase. This allows developers to let the if attribute check the
* converted and validated model values before performing the view action, which results in much more intuitive behavior.
*
* In below example, the FooConverter may convert a non-null parameter to null without causing
* a validation or conversion error, and the intent is to redirect the current page to otherpage.xhtml when
* the converted result is null.
*
* <f:viewParam name="foo" value="#{bean.foo}" converter="fooConverter" />
* <f:viewAction action="otherpage" if="#{bean.foo eq null}" />
*
*
* This is however not possible with standard <f:viewAction> as it evaluates the if
* attribute already before the conversion has taken place. This component solves that by postponing the evaluation of
* the if attribute to the INVOKE_APPLICATION phase.
*
* <f:viewParam name="foo" value="#{bean.foo}" converter="fooConverter" />
* <o:viewAction action="otherpage" if="#{bean.foo eq null}" />
*
*
* Only when you set immediate="true", then it will behave the same as the standard
* <f:viewAction>.
*
*
Usage
*
* You can use it the same way as <f:viewAction>, you only need to change f: to
* o:.
*
* <o:viewAction action="otherpage" if="#{bean.property eq null}" />
*
*
* Messaging
*
* You can use the message attribute to add a global flash warning message.
*
* <o:viewAction ... message="Please use a valid link from within the site" />
*
*
* Note that the message will only be shown when the redirect has actually taken place. The support was added in
* OmniFaces 3.2.
*
* @author Bauke Scholtz
* @since 2.2
*/
@FacesComponent(ViewAction.COMPONENT_TYPE)
public class ViewAction extends UIViewAction {
// Constants ------------------------------------------------------------------------------------------------------
/** The component type, which is {@value org.omnifaces.component.input.ViewAction#COMPONENT_TYPE}. */
public static final String COMPONENT_TYPE = "org.omnifaces.component.input.ViewAction";
enum PropertyKeys {
message
}
// Variables ------------------------------------------------------------------------------------------------------
private final State state = new State(getStateHelper());
// Actions --------------------------------------------------------------------------------------------------------
/**
* Only broadcast the action event when {@link UIViewAction#isRendered()} returns true. The default
* implementation will always broadcast. The {@link UIViewAction#isRendered()} is by default only considered during
* {@link #decode(jakarta.faces.context.FacesContext)}.
*
* If the action event performs any redirect, then add any {@link #getMessage()} as a global flash warning message.
*/
@Override
public void broadcast(FacesEvent event) {
if (super.isRendered()) {
String message = getMessage();
super.broadcast(isEmpty(message) ? event : new RedirectMessageEvent(event, message));
}
}
private static class RedirectMessageEvent extends ActionEvent {
private static final long serialVersionUID = 1L;
private FacesEvent wrapped;
private String message;
public RedirectMessageEvent(FacesEvent wrapped, String message) {
super(wrapped.getComponent());
this.wrapped = wrapped;
this.message = message;
}
@Override
public FacesContext getFacesContext() {
return new RedirectMessageFacesContext(wrapped.getFacesContext(), message);
}
}
private static class RedirectMessageFacesContext extends FacesContextWrapper {
private String message;
public RedirectMessageFacesContext(FacesContext wrapped, String message) {
super(wrapped);
this.message = message;
}
@Override
public ExternalContext getExternalContext() {
return new RedirectMessageExternalContext(getWrapped().getExternalContext(), message);
}
}
private static class RedirectMessageExternalContext extends ExternalContextWrapper {
private String message;
public RedirectMessageExternalContext(ExternalContext wrapped, String message) {
super(wrapped);
this.message = message;
}
@Override
public void redirect(String url) throws IOException {
addFlashGlobalWarn(message);
super.redirect(url);
}
}
// Getters/setters ------------------------------------------------------------------------------------------------
/**
* Returns true if the immediate="true" attribute is not set, otherwise
* delegate to super, hereby maintaining the original behavior of immediate="true".
*/
@Override
public boolean isRendered() {
return !isImmediate() || super.isRendered();
}
/**
* Returns the global flash warning message to be shown in the redirected page.
* @return The global flash warning message to be shown in the redirected page.
* @since 3.2
*/
public String getMessage() {
return state.get(PropertyKeys.message);
}
/**
* Sets the global flash warning message to be shown in the redirected page.
* @param message The global flash warning message to be shown in the redirected page.
* @since 3.2
*/
public void setMessage(String message) {
state.put(PropertyKeys.message, message);
}
}