ExpressionImpl


1   /*
2    * Copyright (c) 1998-2006 Caucho Technology -- all rights reserved
3    *
4    * This file is part of Resin(R) Open Source
5    *
6    * Each copy or derived work must preserve the copyright notice and this
7    * notice unmodified.
8    *
9    * Resin Open Source is free software; you can redistribute it and/or modify
10   * it under the terms of the GNU General Public License as published by
11   * the Free Software Foundation; either version 2 of the License, or
12   * (at your option) any later version.
13   *
14   * Resin Open Source is distributed in the hope that it will be useful,
15   * but WITHOUT ANY WARRANTY; without even the implied warranty of
16   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE, or any warranty
17   * of NON-INFRINGEMENT.  See the GNU General Public License for more
18   * details.
19   *
20   * You should have received a copy of the GNU General Public License
21   * along with Resin Open Source; if not, write to the
22   *   Free SoftwareFoundation, Inc.
23   *   59 Temple Place, Suite 330
24   *   Boston, MA 02111-1307  USA
25   *
26   * @author Scott Ferguson
27   */
28  
29  package com.caucho.jsp.el;
30  
31  import com.caucho.el.Expr;
32  
33  import javax.servlet.jsp.PageContext  ;
34  import javax.servlet.jsp.el.ELException  ;
35  import javax.servlet.jsp.el.Expression  ;
36  import javax.servlet.jsp.el.VariableResolver  ;
37  
38  /**
39   * Implementation of the expression evaluator.
40   */
41  public class ExpressionImpl extends Expression   {
42    private Expr _expr;
43  
44    /**
45     * Implements the expression.
46     */
47    ExpressionImpl(Expr expr)
48    {
49      _expr = expr;
50    }
51    
52    /**
53     * Evaluates an expression.
54     */
55    public Object   evaluate(VariableResolver   resolver)
56      throws ELException  
57    {
58      if (resolver instanceof PageContext  )
59        return _expr.evalObject(((PageContext  ) resolver).getELContext());
60      else
61        return _expr.evalObject(new ELContextAdapter(resolver));
62    }
63  }
64
A to Z: JavaDoc & Examples Daily Java News & Articles Open Source Projects Open Source Codes Free Computer Books Remove Frame
Popular Tags