/* 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;
/*
* This class introduces iterator functionality to Result.
*
* @author fredt@users
* @version 1.7.2
* @since 1.7.2
*/
public class ResultBase {
public Record rRoot;
protected Record rTail;
protected int iSize;
public ResultBase() {}
public ResultIterator iterator() {
return new ResultIterator();
}
public class ResultIterator {
boolean removed;
int counter;
Record current = rRoot;
Record last;
public boolean hasNext() {
return counter < iSize;
}
public boolean next() {
if (hasNext()) {
removed = false;
if (counter != 0) {
last = current;
current = current.next;
}
counter++;
return true;
} else {
return false;
}
}
public boolean previous() {
return false;
}
public boolean absolute(int rows) {
return false;
}
public boolean relative(int rows) {
return false;
}
public boolean beforeFirst() {
return false;
}
public boolean afterLast() {
return false;
}
public boolean isBeforeFirst() {
return false;
}
public boolean isAfterLast() {
return false;
}
public void remove() {
if (counter <= iSize && counter != 0 &&!removed) {
removed = true;
if (current == rTail) {
rTail = last;
}
if (current == rRoot) {
current = rRoot = rRoot.next;
} else {
current = last;
last = null;
current.next = current.next.next;
}
iSize--;
counter--;
return;
}
}
}
}