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Java > Open Source Codes > groovy > lang > SpreadMap


1 /*
2  $Id: SpreadMap.java,v 1.1 2005/05/11 01:17:38 phk Exp $
3
4  Copyright 2003 (C) James Strachan and Bob Mcwhirter. All Rights Reserved.
5
6  Redistribution and use of this software and associated documentation
7  ("Software"), with or without modification, are permitted provided
8  that the following conditions are met:
9
10  1. Redistributions of source code must retain copyright
11     statements and notices. Redistributions must also contain a
12     copy of this document.
13
14  2. Redistributions in binary form must reproduce the
15     above copyright notice, this list of conditions and the
16     following disclaimer in the documentation and/or other
17     materials provided with the distribution.
18
19  3. The name "groovy" must not be used to endorse or promote
20     products derived from this Software without prior written
21     permission of The Codehaus. For written permission,
22     please contact info@codehaus.org.
23
24  4. Products derived from this Software may not be called "groovy"
25     nor may "groovy" appear in their names without prior written
26     permission of The Codehaus. "groovy" is a registered
27     trademark of The Codehaus.
28
29  5. Due credit should be given to The Codehaus -
30     http://groovy.codehaus.org/
31
32  THIS SOFTWARE IS PROVIDED BY THE CODEHAUS AND CONTRIBUTORS
33  ``AS IS'' AND ANY EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT
34  NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
35  FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
36  THE CODEHAUS OR ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
37  INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
38  (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
39  SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
40  HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
41  STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
42  ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
43  OF THE POSSIBILITY OF SUCH DAMAGE.
44
45  */
46 package groovy.lang;
47
48 import java.util.HashMap JavaDoc;
49 import java.util.Map JavaDoc;
50 import java.util.Iterator JavaDoc;
51
52 import org.codehaus.groovy.runtime.InvokerHelper;
53
54 /**
55  * Represents a spreadable map which extends java.util.HashMap.
56  *
57  * @author Pilho Kim
58  * @version $Revision: 1.1 $
59  */
60 public class SpreadMap extends HashMap JavaDoc {
61
62     private Map JavaDoc mapData;
63     private int hashCode;
64
65     public SpreadMap(Object JavaDoc[] values) {
66         mapData = new HashMap JavaDoc(values.length / 2);
67         int i = 0;
68         while (i < values.length) {
69            /// System.out.println(" ... i = " + i);
70 mapData.put(values[i++], values[i++]);
71         }
72            /// System.out.println(" >>> i = " + i);
73 }
74
75     public SpreadMap(Map JavaDoc map) {
76         this.mapData = map;
77     }
78
79     public Object JavaDoc get(Object JavaDoc obj) {
80         return mapData.get(obj);
81     }
82
83     public Object JavaDoc put(Object JavaDoc key, Object JavaDoc value) {
84         throw new RuntimeException JavaDoc("SpreadMap: " + this + " is an immutable map, and so ("
85                                    + key + ": " + value + ") cannot be added.");
86     }
87
88     public Object JavaDoc remove(Object JavaDoc key) {
89         throw new RuntimeException JavaDoc("SpreadMap: " + this + " is an immutable map, and so the key ("
90                                    + key + ") cannot be deleteded.");
91     }
92
93     public void putAll(Map JavaDoc t) {
94         throw new RuntimeException JavaDoc("SpreadMap: " + this + " is an immutable map, and so the map ("
95                                    + t + ") cannot be put in this spreadMap.");
96     }
97
98     public int size() {
99         return mapData.keySet().size();
100     }
101
102     public boolean equals(Object JavaDoc that) {
103         if (that instanceof SpreadMap) {
104             return equals((SpreadMap) that);
105         }
106         return false;
107     }
108
109     public boolean equals(SpreadMap that) {
110         if (this == null && that == null)
111             return true;
112         else if (this != null && that == null)
113             return false;
114         else if (this == null && that != null)
115             return false;
116
117         if (size() == that.size()) {
118             SpreadMap other = (SpreadMap) that;
119             Iterator JavaDoc iter = mapData.keySet().iterator();
120             for (; iter.hasNext(); ) {
121                 Object JavaDoc key = iter.next();
122                 if (! InvokerHelper.compareEqual(get(key), other.get(key)) ) {
123                     return false;
124                 }
125             }
126             return true;
127         }
128         return false;
129     }
130
131
132     public int hashCode() {
133         if (hashCode == 0) {
134             Iterator JavaDoc iter = mapData.keySet().iterator();
135             for (; iter.hasNext(); ) {
136                 Object JavaDoc key = iter.next();
137                 int hash = (key != null) ? key.hashCode() : 0xbabe;
138                 hashCode ^= hash;
139             }
140         }
141         return hashCode;
142     }
143 }
144
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