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HSQLDB - Lightweight 100% Java SQL Database Engine
/* Copyright (c) 2001-2019, 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.lang.reflect.Array;
import java.util.Comparator;
// fredt@users - 1.8.0, 1.9.0 - enhancements
/**
* Intended as an asynchronous alternative to Vector.
*
* @author dnordahl@users
* @version 2.3.3
* @since 1.7.0
*/
public class HsqlArrayList extends BaseList implements HsqlList {
//fredt@users
/*
private static Reporter reporter = new Reporter();
private static class Reporter {
private static int initCounter = 0;
private static int updateCounter = 0;
Reporter() {
try {
System.runFinalizersOnExit(true);
} catch (SecurityException e) {}
}
protected void finalize() {
System.out.println("HsqlArrayList init count: " + initCounter);
System.out.println("HsqlArrayList update count: "
+ updateCounter);
}
}
*/
private static final int DEFAULT_INITIAL_CAPACITY = 8;
private static final float DEFAULT_RESIZE_FACTOR = 2.0f;
Object[] elementData;
Object[] reserveElementData;
private boolean minimizeOnClear;
public HsqlArrayList(Object[] data, int count) {
elementData = data;
elementCount = count;
}
/** Creates a new instance of HsqlArrayList */
public HsqlArrayList() {
// reporter.initCounter++;
elementData = new Object[DEFAULT_INITIAL_CAPACITY];
}
/**
* Creates a new instance of HsqlArrayList that minimizes the size when
* empty
*/
public HsqlArrayList(int initialCapacity, boolean minimize) {
// reporter.initCounter++;
if (initialCapacity < DEFAULT_INITIAL_CAPACITY) {
initialCapacity = DEFAULT_INITIAL_CAPACITY;
}
elementData = new Object[initialCapacity];
minimizeOnClear = minimize;
}
/** Creates a new instance with the given initial capacity */
public HsqlArrayList(int initialCapacity) {
// reporter.initCounter++;
if (initialCapacity < 0) {
throw new NegativeArraySizeException(
"Invalid initial capacity given");
}
if (initialCapacity < DEFAULT_INITIAL_CAPACITY) {
initialCapacity = DEFAULT_INITIAL_CAPACITY;
}
elementData = new Object[initialCapacity];
}
/** Inserts an element at the given index */
public void add(int index, Object element) {
// reporter.updateCounter++;
if (index > elementCount) {
throw new IndexOutOfBoundsException("Index out of bounds: "
+ index + ">" + elementCount);
}
if (index < 0) {
throw new IndexOutOfBoundsException("Index out of bounds: "
+ index + " < 0");
}
if (elementCount >= elementData.length) {
increaseCapacity();
}
if (index < elementCount) {
System.arraycopy(elementData, index, elementData, index + 1, elementCount - index);
}
elementData[index] = element;
elementCount++;
}
/** Appends an element to the end of the list */
public boolean add(Object element) {
// reporter.updateCounter++;
if (elementCount >= elementData.length) {
increaseCapacity();
}
elementData[elementCount] = element;
elementCount++;
return true;
}
/** Gets the element at given position */
public Object get(int index) {
if (index >= elementCount) {
throw new IndexOutOfBoundsException("Index out of bounds: "
+ index + " >= "
+ elementCount);
}
if (index < 0) {
throw new IndexOutOfBoundsException("Index out of bounds: "
+ index + " < 0");
}
return elementData[index];
}
/** returns the index of given object or -1 if not found */
public int indexOf(Object o) {
if (o == null) {
for (int i = 0; i < elementCount; i++) {
if (elementData[i] == null) {
return i;
}
}
return -1;
}
for (int i = 0; i < elementCount; i++) {
if (o.equals(elementData[i])) {
return i;
}
}
return -1;
}
/** Removes and returns the element at given position */
public Object remove(int index) {
if (index >= elementCount) {
throw new IndexOutOfBoundsException("Index out of bounds: "
+ index + " >= "
+ elementCount);
}
if (index < 0) {
throw new IndexOutOfBoundsException("Index out of bounds: "
+ index + " < 0");
}
Object removedObj = elementData[index];
if (index < elementCount - 1) {
System.arraycopy(elementData, index + 1, elementData, index, elementCount - 1 - index);
}
elementCount--;
elementData[elementCount] = null;
if (elementCount == 0) {
clear();
}
return removedObj;
}
/** Replaces the element at given position */
public Object set(int index, Object element) {
if (index >= elementCount) {
throw new IndexOutOfBoundsException("Index out of bounds: "
+ index + " >= "
+ elementCount);
}
if (index < 0) {
throw new IndexOutOfBoundsException("Index out of bounds: "
+ index + " < 0");
}
Object replacedObj = elementData[index];
elementData[index] = element;
return replacedObj;
}
/** Returns the number of elements in the array list */
public final int size() {
return elementCount;
}
private void increaseCapacity() {
int baseSize = elementData.length == 0 ? 1
: elementData.length;
baseSize = (int) (baseSize * DEFAULT_RESIZE_FACTOR);
resize(baseSize);
}
private void resize(int baseSize) {
if (baseSize == elementData.length) {
return;
}
Object[] newArray = (Object[]) Array.newInstance(
elementData.getClass().getComponentType(), baseSize);
int count = elementData.length > newArray.length ? newArray.length
: elementData.length;
System.arraycopy(elementData, 0, newArray, 0, count);
if (minimizeOnClear && reserveElementData == null) {
ArrayUtil.clearArray(ArrayUtil.CLASS_CODE_OBJECT, elementData, 0,
elementData.length);
reserveElementData = elementData;
}
elementData = newArray;
}
/** Trims the array to be the same size as the number of elements. */
public void trim() {
// 0 size array is possible
resize(elementCount);
}
// fredt@users
public void clear() {
if (minimizeOnClear && reserveElementData != null) {
elementData = reserveElementData;
reserveElementData = null;
elementCount = 0;
return;
}
for (int i = 0; i < elementCount; i++) {
elementData[i] = null;
}
elementCount = 0;
}
/**
* Increase or reduce the size, setting discarded or added elements to null.
*/
public void setSize(int newSize) {
if (newSize == 0) {
clear();
return;
}
if (newSize <= elementCount) {
for (int i = newSize; i < elementCount; i++) {
elementData[i] = null;
}
elementCount = newSize;
return;
}
for (; newSize > elementData.length; ) {
increaseCapacity();
}
elementCount = newSize;
}
// fredt@users
public Object[] toArray() {
Object[] newArray = (Object[]) Array.newInstance(
elementData.getClass().getComponentType(), elementCount);
System.arraycopy(elementData, 0, newArray, 0, elementCount);
return newArray;
}
public Object[] toArray(int start, int limit) {
Object[] newArray = (Object[]) Array.newInstance(
elementData.getClass().getComponentType(), limit - start);
System.arraycopy(elementData, start, newArray, 0, limit - start);
return newArray;
}
/**
* Copies all elements of the list to a[]. It is assumed a[] is of the
* correct type. If a[] is too small, a new array or the same type is
* returned. If a[] is larger, only the list elements are copied and no
* other change is made to the array.
* Differs from the implementation in java.util.ArrayList in the second
* aspect.
*/
public Object toArray(Object a) {
if (Array.getLength(a) < elementCount) {
a = Array.newInstance(a.getClass().getComponentType(),
elementCount);
}
System.arraycopy(elementData, 0, a, 0, elementCount);
return a;
}
public void sort(Comparator c) {
if (elementCount < 2) {
return;
}
ArraySort.sort(elementData, elementCount, c);
}
public Object[] getArray() {
return elementData;
}
}