01: /***** BEGIN LICENSE BLOCK *****
02: * Version: CPL 1.0/GPL 2.0/LGPL 2.1
03: *
04: * The contents of this file are subject to the Common Public
05: * License Version 1.0 (the "License"); you may not use this file
06: * except in compliance with the License. You may obtain a copy of
07: * the License at http://www.eclipse.org/legal/cpl-v10.html
08: *
09: * Software distributed under the License is distributed on an "AS
10: * IS" basis, WITHOUT WARRANTY OF ANY KIND, either express or
11: * implied. See the License for the specific language governing
12: * rights and limitations under the License.
13: *
14: * Copyright (C) 2007 Ola Bini <ola.bini@gmail.com>
15: *
16: * Alternatively, the contents of this file may be used under the terms of
17: * either of the GNU General Public License Version 2 or later (the "GPL"),
18: * or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
19: * in which case the provisions of the GPL or the LGPL are applicable instead
20: * of those above. If you wish to allow use of your version of this file only
21: * under the terms of either the GPL or the LGPL, and not to allow others to
22: * use your version of this file under the terms of the CPL, indicate your
23: * decision by deleting the provisions above and replace them with the notice
24: * and other provisions required by the GPL or the LGPL. If you do not delete
25: * the provisions above, a recipient may use your version of this file under
26: * the terms of any one of the CPL, the GPL or the LGPL.
27: ***** END LICENSE BLOCK *****/package org.jvyamlb;
28:
29: /**
30: * @author <a href="mailto:ola.bini@ki.se">Ola Bini</a>
31: */
32: public class IntStack {
33: private int[] values;
34: private int capacity;
35: private int index;
36:
37: public IntStack() {
38: this (27);
39: }
40:
41: public IntStack(int size) {
42: this .values = new int[size];
43: this .capacity = size - 1;
44: this .index = -1;
45: }
46:
47: public boolean isEmpty() {
48: return index == -1;
49: }
50:
51: public int pop() {
52: if (index == -1) {
53: throw new IllegalStateException(
54: "Can't pop from an empty stack");
55: }
56: return values[index--];
57: }
58:
59: public void push(int value) {
60: values[++index] = value;
61: if (index == capacity) {
62: int[] newValues = new int[this .values.length * 2];
63: System.arraycopy(values, 0, newValues, 0,
64: this .values.length);
65: capacity = newValues.length - 1;
66: values = newValues;
67: }
68: }
69: }// IntStack
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