001 package org.apache.turbine.modules;
002
003 /*
004 * Licensed to the Apache Software Foundation (ASF) under one
005 * or more contributor license agreements. See the NOTICE file
006 * distributed with this work for additional information
007 * regarding copyright ownership. The ASF licenses this file
008 * to you under the Apache License, Version 2.0 (the
009 * "License"); you may not use this file except in compliance
010 * with the License. You may obtain a copy of the License at
011 *
012 * http://www.apache.org/licenses/LICENSE-2.0
013 *
014 * Unless required by applicable law or agreed to in writing,
015 * software distributed under the License is distributed on an
016 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
017 * KIND, either express or implied. See the License for the
018 * specific language governing permissions and limitations
019 * under the License.
020 */
021
022 import org.apache.turbine.Turbine;
023 import org.apache.turbine.pipeline.PipelineData;
024 import org.apache.turbine.util.RunData;
025
026 /**
027 * The purpose of this class is to allow one to load and execute Page
028 * modules.
029 *
030 * @author <a href="mailto:mbryson@mont.mindspring.com">Dave Bryson</a>
031 * @author <a href="mailto:hps@intermeta.de">Henning P. Schmiedehausen</a>
032 * @author <a href="mailto:peter@courcoux.biz">Peter Courcoux</a>
033 * @version $Id: PageLoader.java 1078552 2011-03-06 19:58:46Z tv $
034 */
035 public class PageLoader
036 extends GenericLoader<Page>
037 implements Loader<Page>
038 {
039 /** The single instance of this class. */
040 private static PageLoader instance = new PageLoader();
041
042 /**
043 * These ctor's are private to force clients to use getInstance()
044 * to access this class.
045 */
046 private PageLoader()
047 {
048 super();
049 }
050
051 /**
052 * Attempts to load and execute the external page.
053 * @deprecated Use PipelineData version instead.
054 * @param data Turbine information.
055 * @param name Name of object that will execute the page.
056 * @exception Exception a generic exception.
057 */
058 @Deprecated
059 @Override
060 public void exec(RunData data, String name)
061 throws Exception
062 {
063 // Execute page
064 getAssembler(name).build(data);
065 }
066
067 /**
068 * Attempts to load and execute the external page.
069 *
070 * @param data Turbine information.
071 * @param name Name of object that will execute the page.
072 * @exception Exception a generic exception.
073 */
074 @Override
075 public void exec(PipelineData pipelineData, String name)
076 throws Exception
077 {
078 // Execute page
079 getAssembler(name).build(pipelineData);
080 }
081
082
083
084 /**
085 * Pulls out an instance of the object by name. Name is just the
086 * single name of the object. This is equal to getInstance but
087 * returns an Assembler object and is needed to fulfil the Loader
088 * interface.
089 *
090 * @param name Name of object instance.
091 * @return A Screen with the specified name, or null.
092 * @exception Exception a generic exception.
093 */
094 public Page getAssembler(String name)
095 throws Exception
096 {
097 return getAssembler(Page.NAME, name);
098 }
099
100 /**
101 * @see org.apache.turbine.modules.Loader#getCacheSize()
102 */
103 public int getCacheSize()
104 {
105 return PageLoader.getConfiguredCacheSize();
106 }
107
108 /**
109 * The method through which this class is accessed.
110 *
111 * @return The single instance of this class.
112 */
113 public static PageLoader getInstance()
114 {
115 return instance;
116 }
117
118 /**
119 * Helper method to get the configured cache size for this module
120 *
121 * @return the configure cache size
122 */
123 private static int getConfiguredCacheSize()
124 {
125 return Turbine.getConfiguration().getInt(Page.CACHE_SIZE_KEY,
126 Page.CACHE_SIZE_DEFAULT);
127 }
128 }