Java tutorial
/* * * The Apache Software License, Version 1.1 * * Copyright (c) 1999-2003 The Apache Software Foundation. All rights * reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in * the documentation and/or other materials provided with the * distribution. * * 3. The end-user documentation included with the redistribution, if * any, must include the following acknowlegement: * "This product includes software developed by the * Apache Software Foundation (http://www.apache.org/)." * Alternately, this acknowlegement may appear in the software itself, * if and wherever such third-party acknowlegements normally appear. * * 4. The names "The Jakarta Project", "Jakarta Element Construction Set", * "Jakarta ECS" , and "Apache Software Foundation" must not be used * to endorse or promote products derived * from this software without prior written permission. For written * permission, please contact apache@apache.org. * * 5. Products derived from this software may not be called "Apache", * "Jakarta Element Construction Set" nor "Jakarta ECS" nor may "Apache" * appear in their names without prior written permission of the Apache Group. * * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE * DISCLAIMED. IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * */ public class Array implements java.util.Enumeration, java.io.Serializable { private int current = 0; private int size = 10; private int grow = 2; private int place = 0; private Object[] elements = null; private Object[] tmpElements = null; public Array() { init(); } public Array(int size) { setSize(size); init(); } public Array(int size, int grow) { setSize(size); setGrow(grow); init(); } private void init() { elements = new Object[size]; } public Object nextElement() throws java.util.NoSuchElementException { if (elements[place] != null && place != current) { place++; return elements[place - 1]; } else { place = 0; throw new java.util.NoSuchElementException(); } } public boolean hasMoreElements() { if (place < elements.length && current != place) return true; return false; } public void setSize(int size) { this.size = size; } public int getCurrentSize() { return current; } public void rehash() { tmpElements = new Object[size]; int count = 0; for (int x = 0; x < elements.length; x++) { if (elements[x] != null) { tmpElements[count] = elements[x]; count++; } } elements = (Object[]) tmpElements.clone(); tmpElements = null; current = count; } public void setGrow(int grow) { this.grow = grow; } public void grow() { size = size += (size / grow); rehash(); } public void add(Object o) { if (current == elements.length) grow(); try { elements[current] = o; current++; } catch (java.lang.ArrayStoreException ase) { } } public void add(int location, Object o) { try { elements[location] = o; } catch (java.lang.ArrayStoreException ase) { } } public void remove(int location) { elements[location] = null; } public int location(Object o) throws NoSuchObjectException { int loc = -1; for (int x = 0; x < elements.length; x++) { if ((elements[x] != null && elements[x] == o) || (elements[x] != null && elements[x].equals(o))) { loc = x; break; } } if (loc == -1) throw new NoSuchObjectException(); return (loc); } public Object get(int location) { return elements[location]; } public java.util.Enumeration elements() { return this; } } class NoSuchObjectException extends Exception { public NoSuchObjectException() { super("No such object found."); } }