HSQLDB example source code file (BaseList.java)

This example HSQLDB source code file (BaseList.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Java - HSQLDB tags/keywords

baselist, baselistiterator, baselistiterator, iterator, iterator, list, nosuchelementexception, nosuchelementexception, object, object, string, stringbuffer, util

The HSQLDB BaseList.java source code

/* Copyright (c) 2001-2008, The HSQL Development Group
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 * Redistributions of source code must retain the above copyright notice, this
 * list of conditions and the following disclaimer.
 *
 * 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.
 *
 * Neither the name of the HSQL Development Group nor the names of its
 * contributors may be used to endorse or promote products derived from this
 * software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS 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 HSQL DEVELOPMENT GROUP, HSQLDB.ORG,
 * OR 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.
 */


package org.hsqldb.lib;

import java.util.NoSuchElementException;

/**
 * Abstract base for Lists
 *
 * @author Fred Toussi (fredt@users dot sourceforge.net)
 * @version 1.9.0
 * @since 1.7.0
 */
abstract class BaseList {

    protected int elementCount;

    abstract Object get(int index);

    abstract Object remove(int index);

    abstract boolean add(Object o);

    abstract int size();

    public boolean contains(Object o) {
        return indexOf(o) == -1 ? false
                             : true;
    }

    public boolean remove(Object o) {

        int i = indexOf(o);

        if (i == -1) {
            return false;
        }

        remove(i);

        return true;
    }

    public int indexOf(Object o) {

        for (int i = 0, size = size(); i < size; i++) {
            Object current = get(i);

            if (current == null) {
                if (o == null) {
                    return i;
                }
            } else if (current.equals(o)) {
                return i;
            }
        }

        return -1;
    }

    public boolean addAll(Collection other) {

        boolean  result = false;
        Iterator it     = other.iterator();

        while (it.hasNext()) {
            result = true;

            add(it.next());
        }

        return result;
    }

    public boolean addAll(Object[] array) {

        boolean  result = false;
        for (int i = 0; i < array.length; i++) {
            result = true;

            add(array[i]);
        }

        return result;
    }

    public boolean isEmpty() {
        return elementCount == 0;
    }

    /** Returns a string representation */
    public String toString() {

        StringBuffer sb = new StringBuffer(32 + elementCount * 3);

        sb.append("List : size=");
        sb.append(elementCount);
        sb.append(' ');
        sb.append('{');

        Iterator it = iterator();

        while (it.hasNext()) {
            sb.append(it.next());

            if (it.hasNext()) {
                sb.append(',');
                sb.append(' ');
            }
        }

        sb.append('}');

        return sb.toString();
    }

    public Iterator iterator() {
        return new BaseListIterator();
    }

    private class BaseListIterator implements Iterator {

        int     counter = 0;
        boolean removed;

        public boolean hasNext() {
            return counter < elementCount;
        }

        public Object next() {

            if (counter < elementCount) {
                removed = false;

                Object returnValue = get(counter);

                counter++;

                return returnValue;
            }

            throw new NoSuchElementException();
        }

        public int nextInt() {
            throw new NoSuchElementException();
        }

        public long nextLong() {
            throw new NoSuchElementException();
        }

        public void remove() {

            if (removed) {
                throw new NoSuchElementException("Iterator");
            }

            removed = true;

            if (counter != 0) {
                BaseList.this.remove(counter - 1);

                counter--;    // above can throw, so decrement if successful

                return;
            }

            throw new NoSuchElementException();
        }

        public void setValue(Object value) {
            throw new NoSuchElementException();
        }
    }
}