| /* |
| * $Id$ |
| * |
| * 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.tiles.el; |
| |
| import java.beans.FeatureDescriptor; |
| import java.util.ArrayList; |
| import java.util.Iterator; |
| import java.util.List; |
| import java.util.Map; |
| |
| import javax.el.ELContext; |
| import javax.el.ELResolver; |
| |
| import org.apache.tiles.request.Request; |
| |
| /** |
| * Resolves beans in request, session and application scope. |
| * |
| * @version $Rev$ $Date$ |
| * @since 2.2.1 |
| */ |
| public class TilesContextBeanELResolver extends ELResolver { |
| |
| /** {@inheritDoc} */ |
| @Override |
| public Class<?> getCommonPropertyType(ELContext context, Object base) { |
| // only resolve at the root of the context |
| if (base != null) { |
| return null; |
| } |
| |
| return String.class; |
| } |
| |
| /** {@inheritDoc} */ |
| @Override |
| public Iterator<FeatureDescriptor> getFeatureDescriptors(ELContext context, |
| Object base) { |
| List<FeatureDescriptor> list = new ArrayList<FeatureDescriptor>(); |
| |
| Request request = (Request) context |
| .getContext(Request.class); |
| for (String scope : request.getAvailableScopes()) { |
| collectBeanInfo(request.getContext(scope), list); |
| } |
| return list.iterator(); |
| } |
| |
| /** {@inheritDoc} */ |
| @Override |
| public Class<?> getType(ELContext context, Object base, Object property) { |
| if (base != null) { |
| return null; |
| } |
| |
| Object obj = findObjectByProperty(context, property); |
| if (obj != null) { |
| context.setPropertyResolved(true); |
| return obj.getClass(); |
| } |
| return null; |
| } |
| |
| /** {@inheritDoc} */ |
| @Override |
| public Object getValue(ELContext context, Object base, Object property) { |
| if (base != null) { |
| return null; |
| } |
| |
| Object retValue = findObjectByProperty(context, property); |
| |
| if (retValue != null) { |
| context.setPropertyResolved(true); |
| } |
| |
| return retValue; |
| } |
| |
| /** {@inheritDoc} */ |
| @Override |
| public boolean isReadOnly(ELContext context, Object base, Object property) { |
| if (context == null) { |
| throw new NullPointerException(); |
| } |
| |
| return true; |
| } |
| |
| /** {@inheritDoc} */ |
| @Override |
| public void setValue(ELContext context, Object base, Object property, |
| Object value) { |
| // Does nothing for the moment. |
| } |
| |
| /** |
| * Collects bean infos from a map's values and filling a list. |
| * |
| * @param map The map containing the bean to be inspected. |
| * @param list The list to fill. |
| * @since 2.2.1 |
| */ |
| protected void collectBeanInfo(Map<String, ? extends Object> map, |
| List<FeatureDescriptor> list) { |
| if (map == null || map.isEmpty()) { |
| return; |
| } |
| |
| for (Map.Entry<String, ? extends Object> entry : map.entrySet()) { |
| FeatureDescriptor descriptor = new FeatureDescriptor(); |
| descriptor.setDisplayName(entry.getKey()); |
| descriptor.setExpert(false); |
| descriptor.setHidden(false); |
| descriptor.setName(entry.getKey()); |
| descriptor.setPreferred(true); |
| descriptor.setShortDescription(""); |
| descriptor.setValue("type", String.class); |
| descriptor.setValue("resolvableAtDesignTime", Boolean.FALSE); |
| list.add(descriptor); |
| } |
| } |
| |
| /** |
| * Finds an object in request, session or application scope, in this order. |
| * |
| * @param context The context to use. |
| * @param property The property used as an attribute name. |
| * @return The found bean, if it exists, or <code>null</code> otherwise. |
| * @since 2.2.1 |
| */ |
| protected Object findObjectByProperty(ELContext context, Object property) { |
| Object retValue = null; |
| |
| Request request = (Request) context |
| .getContext(Request.class); |
| |
| String prop = property.toString(); |
| |
| String[] scopes = request.getAvailableScopes().toArray(new String[0]); |
| int i = 0; |
| do { |
| retValue = getObject(request.getContext(scopes[i]), prop); |
| i++; |
| } while (retValue == null && i < scopes.length); |
| |
| return retValue; |
| } |
| |
| /** |
| * Returns an object from a map in a null-safe manner. |
| * |
| * @param map The map to use. |
| * @param property The property to use as a key. |
| * @return The object, if present, or <code>null</code> otherwise. |
| * @since 2.2.1 |
| */ |
| protected Object getObject(Map<String, ? extends Object> map, |
| String property) { |
| Object retValue = null; |
| if (map != null) { |
| retValue = map.get(property); |
| } |
| return retValue; |
| } |
| } |