KickJava   Java API By Example, From Geeks To Geeks.

Java > Open Source Codes > com > sun > el > parser > AstEmpty


1 /*
2  * The contents of this file are subject to the terms
3  * of the Common Development and Distribution License
4  * (the "License"). You may not use this file except
5  * in compliance with the License.
6  *
7  * You can obtain a copy of the license at
8  * glassfish/bootstrap/legal/CDDLv1.0.txt or
9  * https://glassfish.dev.java.net/public/CDDLv1.0.html.
10  * See the License for the specific language governing
11  * permissions and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL
14  * HEADER in each file and include the License file at
15  * glassfish/bootstrap/legal/CDDLv1.0.txt. If applicable,
16  * add the following below this CDDL HEADER, with the
17  * fields enclosed by brackets "[]" replaced with your
18  * own identifying information: Portions Copyright [yyyy]
19  * [name of copyright owner]
20  *
21  * Copyright 2005 Sun Microsystems, Inc. All rights reserved.
22  *//* Generated By:JJTree: Do not edit this line. AstEmpty.java */
23
24 package com.sun.el.parser;
25
26 import java.util.Collection JavaDoc;
27 import java.util.Map JavaDoc;
28
29 import javax.el.ELException;
30
31 import com.sun.el.lang.EvaluationContext;
32
33 /**
34  * @author Jacob Hookom [jacob@hookom.net]
35  * @version $Change: 181177 $$DateTime: 2001/06/26 08:45:09 $$Author: kchung $
36  */
37 public final class AstEmpty extends SimpleNode {
38     public AstEmpty(int id) {
39         super(id);
40     }
41
42     public Class JavaDoc getType(EvaluationContext ctx)
43             throws ELException {
44         return Boolean JavaDoc.class;
45     }
46
47     public Object JavaDoc getValue(EvaluationContext ctx)
48             throws ELException {
49         Object JavaDoc obj = this.children[0].getValue(ctx);
50         if (obj == null) {
51             return Boolean.TRUE;
52         } else if (obj instanceof String JavaDoc) {
53             return Boolean.valueOf(((String JavaDoc) obj).length() == 0);
54         } else if (obj instanceof Object JavaDoc[]) {
55             return Boolean.valueOf(((Object JavaDoc[]) obj).length == 0);
56         } else if (obj instanceof Collection JavaDoc) {
57             return Boolean.valueOf(((Collection JavaDoc) obj).isEmpty());
58         } else if (obj instanceof Map JavaDoc) {
59             return Boolean.valueOf(((Map JavaDoc) obj).isEmpty());
60         }
61         return Boolean.FALSE;
62     }
63 }
64
Popular Tags