/*
* Copyright 2006 The Apache Software Foundation
*
* 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 javax.servlet.jsp.el;
import java.beans.FeatureDescriptor;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Enumeration;
import java.util.Iterator;
import java.util.List;
import javax.el.ELContext;
import javax.el.ELException;
import javax.el.ELResolver;
import javax.el.PropertyNotFoundException;
import javax.el.PropertyNotWritableException;
import javax.servlet.jsp.JspContext;
import javax.servlet.jsp.PageContext;
public class ScopedAttributeELResolver extends ELResolver {
public ScopedAttributeELResolver() {
super();
}
public Object getValue(ELContext context, Object base, Object property)
throws NullPointerException, PropertyNotFoundException, ELException {
if (context == null) {
throw new NullPointerException();
}
if (base == null) {
context.setPropertyResolved(true);
if (property != null) {
String key = property.toString();
PageContext page = (PageContext) context
.getContext(JspContext.class);
return page.findAttribute(key);
}
}
return null;
}
public Class getType(ELContext context, Object base, Object property)
throws NullPointerException, PropertyNotFoundException, ELException {
if (context == null) {
throw new NullPointerException();
}
if (base == null) {
context.setPropertyResolved(true);
return Object.class;
}
return null;
}
public void setValue(ELContext context, Object base, Object property,
Object value) throws NullPointerException,
PropertyNotFoundException, PropertyNotWritableException,
ELException {
if (context == null) {
throw new NullPointerException();
}
if (base == null) {
context.setPropertyResolved(true);
if (property != null) {
String key = property.toString();
PageContext page = (PageContext) context
.getContext(JspContext.class);
int scope = page.getAttributesScope(key);
if (scope != 0) {
page.setAttribute(key, value, scope);
} else {
page.setAttribute(key, value);
}
}
}
}
public boolean isReadOnly(ELContext context, Object base, Object property)
throws NullPointerException, PropertyNotFoundException, ELException {
if (context == null) {
throw new NullPointerException();
}
if (base == null) {
context.setPropertyResolved(true);
}
return false;
}
public Iterator<FeatureDescriptor> getFeatureDescriptors(ELContext context, Object base) {
PageContext ctxt = (PageContext) context.getContext(JspContext.class);
List<FeatureDescriptor> list = new ArrayList<FeatureDescriptor>();
Enumeration e;
Object value;
String name;
e = ctxt.getAttributeNamesInScope(PageContext.PAGE_SCOPE);
while (e.hasMoreElements()) {
name = (String) e.nextElement();
value = ctxt.getAttribute(name, PageContext.PAGE_SCOPE);
FeatureDescriptor descriptor = new FeatureDescriptor();
descriptor.setName(name);
descriptor.setDisplayName(name);
descriptor.setExpert(false);
descriptor.setHidden(false);
descriptor.setPreferred(true);
descriptor.setShortDescription("page scoped attribute");
descriptor.setValue("type", value.getClass());
descriptor.setValue("resolvableAtDesignTime", Boolean.FALSE);
list.add(descriptor);
}
e = ctxt.getAttributeNamesInScope(PageContext.REQUEST_SCOPE);
while (e.hasMoreElements()) {
name = (String) e.nextElement();
value = ctxt.getAttribute(name, PageContext.REQUEST_SCOPE);
FeatureDescriptor descriptor = new FeatureDescriptor();
descriptor.setName(name);
descriptor.setDisplayName(name);
descriptor.setExpert(false);
descriptor.setHidden(false);
descriptor.setPreferred(true);
descriptor.setShortDescription("request scope attribute");
descriptor.setValue("type", value.getClass());
descriptor.setValue("resolvableAtDesignTime", Boolean.FALSE);
list.add(descriptor);
}
if (ctxt.getSession() != null) {
e = ctxt.getAttributeNamesInScope(PageContext.SESSION_SCOPE);
while (e.hasMoreElements()) {
name = (String) e.nextElement();
value = ctxt.getAttribute(name, PageContext.SESSION_SCOPE);
FeatureDescriptor descriptor = new FeatureDescriptor();
descriptor.setName(name);
descriptor.setDisplayName(name);
descriptor.setExpert(false);
descriptor.setHidden(false);
descriptor.setPreferred(true);
descriptor.setShortDescription("session scoped attribute");
descriptor.setValue("type", value.getClass());
descriptor.setValue("resolvableAtDesignTime", Boolean.FALSE);
list.add(descriptor);
}
}
e = ctxt.getAttributeNamesInScope(PageContext.APPLICATION_SCOPE);
while (e.hasMoreElements()) {
name = (String) e.nextElement();
value = ctxt.getAttribute(name, PageContext.APPLICATION_SCOPE);
FeatureDescriptor descriptor = new FeatureDescriptor();
descriptor.setName(name);
descriptor.setDisplayName(name);
descriptor.setExpert(false);
descriptor.setHidden(false);
descriptor.setPreferred(true);
descriptor.setShortDescription("application scoped attribute");
descriptor.setValue("type", value.getClass());
descriptor.setValue("resolvableAtDesignTime", Boolean.FALSE);
list.add(descriptor);
}
return list.iterator();
}
private static void appendEnumeration(Collection c, Enumeration e) {
while (e.hasMoreElements()) {
c.add(e.nextElement());
}
}
public Class<String> getCommonPropertyType(ELContext context, Object base) {
if (base == null) {
return String.class;
}
return null;
}
}