| /* |
| * Copyright 2004-2005 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 org.apache.tiles; |
| |
| import java.io.Serializable; |
| import java.util.Collections; |
| import java.util.HashMap; |
| import java.util.Iterator; |
| import java.util.Map; |
| import java.util.Set; |
| |
| import javax.servlet.ServletRequest; |
| import javax.servlet.jsp.PageContext; |
| |
| import org.apache.taglib.tiles.ComponentConstants; |
| |
| /** |
| * Component context. |
| */ |
| public class ComponentContext implements Serializable { |
| |
| /** |
| * Component attributes. |
| */ |
| private Map attributes=null; |
| |
| /** |
| * Constructor. |
| */ |
| public ComponentContext() { |
| super(); |
| } |
| |
| /** |
| * Constructor. |
| * Create a context and set specified attributes. |
| * @param attributes Attributes to initialize context. |
| */ |
| public ComponentContext(Map attributes) { |
| if (attributes != null) { |
| this.attributes = new HashMap(attributes); |
| } |
| } |
| |
| /** |
| * Add all attributes to this context. |
| * Copies all of the mappings from the specified attribute map to this context. |
| * New attribute mappings will replace any mappings that this context had for any of the keys |
| * currently in the specified attribute map. |
| * @param newAttributes Attributes to add. |
| */ |
| public void addAll(Map newAttributes) { |
| if (attributes == null) { |
| attributes = new HashMap(newAttributes); |
| return; |
| } |
| |
| attributes.putAll(newAttributes); |
| } |
| |
| /** |
| * Add all missing attributes to this context. |
| * Copies all of the mappings from the specified attributes map to this context. |
| * New attribute mappings will be added only if they don't already exist in |
| * this context. |
| * @param defaultAttributes Attributes to add. |
| */ |
| public void addMissing(Map defaultAttributes) { |
| if (defaultAttributes == null) { |
| return; |
| } |
| |
| if (attributes == null) { |
| attributes = new HashMap(defaultAttributes); |
| return; |
| } |
| |
| Set entries = defaultAttributes.entrySet(); |
| Iterator iterator = entries.iterator(); |
| while (iterator.hasNext()) { |
| Map.Entry entry = (Map.Entry) iterator.next(); |
| if (!attributes.containsKey(entry.getKey())) { |
| attributes.put(entry.getKey(), entry.getValue()); |
| } |
| } |
| } |
| |
| /** |
| * Get an attribute from context. |
| * @param name Name of the attribute. |
| * @return <{Object}> |
| */ |
| public Object getAttribute(String name) { |
| if (attributes == null){ |
| return null; |
| } |
| |
| return attributes.get(name); |
| } |
| |
| /** |
| * Get names of all attributes. |
| * @return <{Object}> |
| */ |
| public Iterator getAttributeNames() { |
| if (attributes == null) { |
| return Collections.EMPTY_LIST.iterator(); |
| } |
| |
| return attributes.keySet().iterator(); |
| } |
| |
| /** |
| * Put a new attribute to context. |
| * @param name Name of the attribute. |
| * @param value Value of the attribute. |
| */ |
| public void putAttribute(String name, Object value) { |
| if (attributes == null) { |
| attributes = new HashMap(); |
| } |
| |
| attributes.put(name, value); |
| } |
| |
| /** |
| * Find object in one of the contexts. |
| * Order : component then pageContext.findAttribute() |
| * @param beanName Name of the bean to find. |
| * @param pageContext Page context. |
| * @return Requested bean or <code>null</code> if not found. |
| */ |
| public Object findAttribute(String beanName, PageContext pageContext) { |
| Object attribute = getAttribute(beanName); |
| if (attribute == null) { |
| attribute = pageContext.findAttribute(beanName); |
| } |
| |
| return attribute; |
| } |
| |
| /** |
| * Get object from requested context. |
| * Context can be 'component'. |
| * @param beanName Name of the bean to find. |
| * @param scope Search scope (see {@link PageContext}). |
| * @param pageContext Page context. |
| * @return requested bean or <code>null</code> if not found. |
| */ |
| public Object getAttribute( |
| String beanName, |
| int scope, |
| PageContext pageContext) { |
| |
| if (scope == ComponentConstants.COMPONENT_SCOPE){ |
| return getAttribute(beanName); |
| } |
| |
| return pageContext.getAttribute(beanName, scope); |
| } |
| |
| /** |
| * Get component context from request. |
| * @param request ServletRequest. |
| * @return ComponentContext |
| */ |
| static public ComponentContext getContext(ServletRequest request) { |
| return (ComponentContext) request.getAttribute( |
| ComponentConstants.COMPONENT_CONTEXT); |
| } |
| |
| /** |
| * Store component context into request. |
| * @param context ComponentContext to store. |
| * @param request Request to store ComponentContext. |
| */ |
| static public void setContext( |
| ComponentContext context, |
| ServletRequest request) { |
| |
| request.setAttribute(ComponentConstants.COMPONENT_CONTEXT, context); |
| } |
| } |