2009/05/20 - Apache Shale has been retired.

For more information, please explore the Attic.


1   /*
2    * Licensed to the Apache Software Foundation (ASF) under one or more
3    * contributor license agreements.  See the NOTICE file distributed with
4    * this work for additional information regarding copyright ownership.
5    * The ASF licenses this file to you under the Apache License, Version 2.0
6    * (the "License"); you may not use this file except in compliance with
7    * the License.  You may obtain a copy of the License at
8    *
9    *      http://www.apache.org/licenses/LICENSE-2.0
10   *
11   * Unless required by applicable law or agreed to in writing, software
12   * distributed under the License is distributed on an "AS IS" BASIS,
13   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14   * See the License for the specific language governing permissions and
15   * limitations under the License.
16   */
17  
18  /*
19   * $Id: JSFRuntimeTracker.java 465411 2006-10-18 23:06:50Z gvanmatre $
20   */
21  
22  package org.apache.shale.clay.utils;
23  
24  /***
25   * <p>This utility class is used to determine the
26   * JSF runtime that will take presidency.</p>
27   */
28  public final class JSFRuntimeTracker {
29  
30      /***
31       * <p>Utility Class hides the default constructor.</p>
32       */
33      private JSFRuntimeTracker() {
34          super();
35      }
36  
37      /***
38       * <p>This enumeration indicates the JSF RI 1.1.x runtime is installed.</p>
39       */
40      public static final int RI_1_1 = 0;
41  
42      /***
43       * <p>This enumeration indicates the MyFaces 1.1.x runtime is installed.</p>
44       */
45      public static final int MYFACES_1_1 = 1;
46  
47      /***
48       * <p>This enumeration indicates the JSF RI 1.2.x runtime is installed.</p>
49       */
50      public static final int RI_1_2 = 2;
51  
52      /***
53       * <p>Captures the active runtime once determined.</p>
54       */
55      private static int activeRuntime = -1;
56  
57      /***
58       * <p>This method will try to load some key classes in the various runtimes
59       * to determine the active runtime.  The enumerations are as follows:
60       * <code>RI_1_1</code>, <code>MYFACES_1_1</code>, <code>RI_1_2</code>.</p>
61       *
62       * @return an enumeration that indicates the active JSF runtime
63       */
64      public static int getJsfRuntime() {
65          if (activeRuntime > 0) {
66              return activeRuntime;
67          }
68          try {
69              // JSF RI 1.2
70              Class.forName("com.sun.faces.config.JSFVersionTracker");
71              activeRuntime = RI_1_2;
72          } catch (ClassNotFoundException e1) {
73              try {
74                  Class.forName("org.apache.myfaces.application.jsp.JspViewHandlerImpl");
75                  activeRuntime = MYFACES_1_1;  //myfaces 1.1.x
76              } catch (ClassNotFoundException e2) {
77                  activeRuntime = RI_1_1; //JSF RI 1.1
78              }
79          }
80  
81          return activeRuntime;
82      }
83  }