/*
* 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.myfaces.tobago.internal.taglib.component;
import org.apache.myfaces.tobago.apt.annotation.BodyContent;
import org.apache.myfaces.tobago.apt.annotation.Tag;
import org.apache.myfaces.tobago.apt.annotation.TagAttribute;
import org.apache.myfaces.tobago.apt.annotation.SimpleTag;
import org.apache.myfaces.tobago.event.TabChangeListener;
import org.apache.myfaces.tobago.event.TabChangeSource;
import org.apache.myfaces.tobago.event.ValueExpressionTabChangeListener;
import javax.el.ELContext;
import javax.el.ValueExpression;
import javax.faces.component.UIComponent;
import javax.faces.context.FacesContext;
import javax.faces.webapp.UIComponentClassicTagBase;
import javax.faces.webapp.UIComponentELTag;
import javax.servlet.jsp.JspException;
import javax.servlet.jsp.tagext.TagSupport;
/**
* Register an TabChangedListener instance on the UIComponent
* associated with the closest parent UIComponent custom action.
*/
@Tag(name = "tabChangeListener", bodyContent = BodyContent.EMPTY)
@SimpleTag(
faceletHandler = "org.apache.myfaces.tobago.facelets.TabChangeListenerHandler")
public abstract class TabChangeListenerTag extends TagSupport {
private static final long serialVersionUID = 2L;
private ValueExpression type;
private ValueExpression binding;
/**
* Fully qualified Java class name of a TabChangeListener to be
* created and registered.
*/
@TagAttribute(required = true, name = "type", type = "java.lang.String")
public void setType(ValueExpression type) {
this.type = type;
}
/**
* The value binding expression to a TabChangeListener.
*/
@TagAttribute(name = "binding", type = "org.apache.myfaces.tobago.event.TabChangeListener")
public void setBinding(ValueExpression binding) {
this.binding = binding;
}
/**
* <p>Create a new instance of the specified {@link TabChangeListener}
* class, and register it with the {@link javax.faces.component.UIComponent} instance associated
* with our most immediately surrounding {@link javax.faces.webapp.UIComponentELTag} instance, if
* the {@link javax.faces.component.UIComponent} instance was created by this execution of the
* containing JSP page.</p>
*
* @throws JspException if a JSP error occurs
*/
public int doStartTag() throws JspException {
// Locate our parent UIComponentTag
UIComponentClassicTagBase tag =
UIComponentELTag.getParentUIComponentClassicTagBase(pageContext);
if (tag == null) {
// TODO Message resource i18n
throw new JspException("Not nested in faces tag");
}
if (!tag.getCreated()) {
return (SKIP_BODY);
}
UIComponent component = tag.getComponentInstance();
if (component == null) {
// TODO Message resource i18n
throw new JspException("Component Instance is null");
}
if (!(component instanceof TabChangeSource)) {
// TODO Message resource i18n
throw new JspException("Component " + component.getClass().getName() + " is not instanceof TabChangeSource");
}
TabChangeSource changeSource = (TabChangeSource) component;
final ELContext elContext = FacesContext.getCurrentInstance().getELContext();
TabChangeListener handler = null;
if (binding != null && !binding.isLiteralText()) {
Object value = binding.getValue(elContext);
if (value instanceof TabChangeListener) {
handler = (TabChangeListener) value;
}
}
if (handler == null && type != null) {
handler = createTabChangeListener((String) type.getValue(elContext));
if (handler != null && binding != null) {
binding.setValue(elContext, handler);
}
}
if (handler != null) {
if (binding != null) {
changeSource.addTabChangeListener(
new ValueExpressionTabChangeListener((String) type.getValue(elContext), binding));
} else {
changeSource.addTabChangeListener(handler);
}
}
return (SKIP_BODY);
}
/**
* <p>Create and return a new {@link TabChangeListener} to be registered
* on our surrounding {@link javax.faces.component.UIComponent}.</p>
*
* @throws javax.servlet.jsp.JspException if a new instance cannot be created
*/
protected TabChangeListener createTabChangeListener(String className) throws JspException {
try {
Class clazz = getClass().getClassLoader().loadClass(className);
return ((TabChangeListener) clazz.newInstance());
} catch (Exception e) {
throw new JspException(e);
}
}
}