1 package org.apache.turbine.modules;
2
3 /*
4 * Licensed to the Apache Software Foundation (ASF) under one
5 * or more contributor license agreements. See the NOTICE file
6 * distributed with this work for additional information
7 * regarding copyright ownership. The ASF licenses this file
8 * to you under the Apache License, Version 2.0 (the
9 * "License"); you may not use this file except in compliance
10 * with the License. You may obtain a copy of the License at
11 *
12 * http://www.apache.org/licenses/LICENSE-2.0
13 *
14 * Unless required by applicable law or agreed to in writing,
15 * software distributed under the License is distributed on an
16 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
17 * KIND, either express or implied. See the License for the
18 * specific language governing permissions and limitations
19 * under the License.
20 */
21
22 import org.apache.turbine.Turbine;
23 import org.apache.turbine.pipeline.PipelineData;
24
25 /**
26 * The purpose of this class is to allow one to load and execute Page
27 * modules.
28 *
29 * @author <a href="mailto:mbryson@mont.mindspring.com">Dave Bryson</a>
30 * @author <a href="mailto:hps@intermeta.de">Henning P. Schmiedehausen</a>
31 * @author <a href="mailto:peter@courcoux.biz">Peter Courcoux</a>
32 * @version $Id: PageLoader.java 1706239 2015-10-01 13:18:35Z tv $
33 */
34 public class PageLoader
35 extends GenericLoader<Page>
36 implements Loader<Page>
37 {
38 /** The single instance of this class. */
39 private static PageLoader instance = new PageLoader();
40
41 /**
42 * These ctor's are private to force clients to use getInstance()
43 * to access this class.
44 */
45 private PageLoader()
46 {
47 super();
48 }
49
50 /**
51 * Attempts to load and execute the external page.
52 *
53 * @param pipelineData Turbine information.
54 * @param name Name of object that will execute the page.
55 * @exception Exception a generic exception.
56 */
57 @Override
58 public void exec(PipelineData pipelineData, String name)
59 throws Exception
60 {
61 // Execute page
62 getAssembler(name).build(pipelineData);
63 }
64
65 /**
66 * Pulls out an instance of the object by name. Name is just the
67 * single name of the object.
68 *
69 * @param name Name of object instance.
70 * @return A Screen with the specified name, or null.
71 * @exception Exception a generic exception.
72 */
73 @Override
74 public Page getAssembler(String name)
75 throws Exception
76 {
77 return getAssembler(Page.class, name);
78 }
79
80 /**
81 * @see org.apache.turbine.modules.Loader#getCacheSize()
82 */
83 @Override
84 public int getCacheSize()
85 {
86 return PageLoader.getConfiguredCacheSize();
87 }
88
89 /**
90 * The method through which this class is accessed.
91 *
92 * @return The single instance of this class.
93 */
94 public static PageLoader getInstance()
95 {
96 return instance;
97 }
98
99 /**
100 * Helper method to get the configured cache size for this module
101 *
102 * @return the configure cache size
103 */
104 private static int getConfiguredCacheSize()
105 {
106 return Turbine.getConfiguration().getInt(Page.CACHE_SIZE_KEY,
107 Page.CACHE_SIZE_DEFAULT);
108 }
109 }