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
028 * Layout 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: LayoutLoader.java 1078552 2011-03-06 19:58:46Z tv $
034 */
035 public class LayoutLoader
036 extends GenericLoader<Layout>
037 implements Loader<Layout>
038 {
039 /** The single instance of this class. */
040 private static LayoutLoader instance = new LayoutLoader();
041
042 /**
043 * These ctor's are private to force clients to use getInstance()
044 * to access this class.
045 */
046 private LayoutLoader()
047 {
048 super();
049 }
050
051 /**
052 * Attempts to load and execute the external layout.
053 *
054 * @deprecated Use PipelineData version instead.
055 * @param data Turbine information.
056 * @param name Name of object that will execute the layout.
057 * @exception Exception a generic exception.
058 */
059 @Deprecated
060 @Override
061 public void exec(RunData data, String name)
062 throws Exception
063 {
064 // Execute layout
065 getAssembler(name).build(data);
066 }
067
068 /**
069 * Attempts to load and execute the external layout.
070 *
071 * @param pipelineData Turbine information.
072 * @param name Name of object that will execute the layout.
073 * @exception Exception a generic exception.
074 */
075 @Override
076 public void exec(PipelineData pipelineData, String name)
077 throws Exception
078 {
079 getAssembler(name).build(pipelineData);
080 }
081
082 /**
083 * Pulls out an instance of the object by name. Name is just the
084 * single name of the object. This is equal to getInstance but
085 * returns an Assembler object and is needed to fulfil the Loader
086 * interface.
087 *
088 * @param name Name of object instance.
089 * @return A Layout with the specified name, or null.
090 * @exception Exception a generic exception.
091 */
092 public Layout getAssembler(String name)
093 throws Exception
094 {
095 return getAssembler(Layout.NAME, name);
096 }
097
098 /**
099 * @see org.apache.turbine.modules.Loader#getCacheSize()
100 */
101 public int getCacheSize()
102 {
103 return LayoutLoader.getConfiguredCacheSize();
104 }
105
106 /**
107 * The method through which this class is accessed.
108 *
109 * @return The single instance of this class.
110 */
111 public static LayoutLoader getInstance()
112 {
113 return instance;
114 }
115
116 /**
117 * Helper method to get the configured cache size for this module
118 *
119 * @return the configure cache size
120 */
121 private static int getConfiguredCacheSize()
122 {
123 return Turbine.getConfiguration().getInt(Layout.CACHE_SIZE_KEY,
124 Layout.CACHE_SIZE_DEFAULT);
125 }
126 }