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SquidLib platform-independent logic and utility code. Please refer to
https://github.com/SquidPony/SquidLib .
/*******************************************************************************
* Copyright 2011 See AUTHORS file.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
******************************************************************************/
package squidpony.squidmath;
import java.io.Serializable;
import java.util.Arrays;
/** A resizable, ordered or unordered short variable-length array. Avoids the boxing that occurs with {@code ArrayList}.
* If unordered, this class avoids a memory copy when removing elements (the last element is moved to the removed
* element's position). Used internally by CoordPacker, and unlikely to be used outside of it.
*
* Was called IntArray in libGDX; to avoid confusion with the fixed-length primitive array type, VLA (variable-length
* array) was chosen as a different name. Also uses short instead of int, of course.
* Copied from LibGDX by Tommy Ettinger on 10/1/2015.
* @author Nathan Sweet */
public class ShortVLA implements Serializable{
private static final long serialVersionUID = -2948161891082748626L;
public short[] items;
public int size;
public boolean ordered;
/** Creates an ordered array with a capacity of 16. */
public ShortVLA() {
this(true, 16);
}
/** Creates an ordered array with the specified capacity. */
public ShortVLA(int capacity) {
this(true, capacity);
}
/** @param ordered If false, methods that remove elements may change the order of other elements in the array, which avoids a
* memory copy.
* @param capacity Any elements added beyond this will cause the backing array to be grown. */
public ShortVLA(boolean ordered, int capacity) {
this.ordered = ordered;
items = new short[capacity];
}
/** Creates a new array containing the elements in the specific array. The new array will be ordered if the specific array is
* ordered. The capacity is set to the number of elements, so any subsequent elements added will cause the backing array to be
* grown. */
public ShortVLA(ShortVLA array) {
ordered = array.ordered;
size = array.size;
items = new short[size];
System.arraycopy(array.items, 0, items, 0, size);
}
/** Creates a new ordered array containing the elements in the specified array. The capacity is set to the number of elements,
* so any subsequent elements added will cause the backing array to be grown. */
public ShortVLA(short[] array) {
this(true, array, 0, array.length);
}
/** Creates a new ordered array containing the elements in the specified array, converted to short. The capacity is set to
* the number of elements, so any subsequent elements added will cause the backing array to be grown. */
public ShortVLA(int[] array) {
this(true, array.length);
for (int i = 0; i < array.length; i++) {
items[size + i] = (short) array[i];
}
size += array.length;
}
/** Creates a new array containing the elements in the specified array. The capacity is set to the number of elements, so any
* subsequent elements added will cause the backing array to be grown.
* @param ordered If false, methods that remove elements may change the order of other elements in the array, which avoids a
* memory copy.
*/
public ShortVLA(boolean ordered, short[] array, int startIndex, int count) {
this(ordered, count);
size = count;
System.arraycopy(array, startIndex, items, 0, count);
}
public void add (short value) {
short[] items = this.items;
if (size == items.length) items = resize(Math.max(8, (int)(size * 1.75f)));
items[size++] = value;
}
public void addAll (ShortVLA array) {
addAll(array, 0, array.size);
}
public void addAll (ShortVLA array, int offset, int length) {
if (offset + length > array.size)
throw new IllegalArgumentException("offset + length must be <= size: " + offset + " + " + length + " <= " + array.size);
addAll(array.items, offset, length);
}
public void addAll (short... array) {
addAll(array, 0, array.length);
}
public void addAll (short[] array, int offset, int length) {
short[] items = this.items;
int sizeNeeded = size + length;
if (sizeNeeded > items.length) items = resize(Math.max(8, (int)(sizeNeeded * 1.75f)));
System.arraycopy(array, offset, items, size, length);
size += length;
}
public void addAll (int[] array) {
short[] items = this.items;
int sizeNeeded = size + array.length;
if (sizeNeeded > items.length) items = resize(Math.max(8, (int)(sizeNeeded * 1.75f)));
for (int i = 0; i < array.length; i++) {
items[size + i] = (short) array[i];
}
size += array.length;
}
public void addRange (int start, int end) {
short[] items = this.items;
int sizeNeeded = size + end - start;
if (sizeNeeded > items.length) items = resize(Math.max(8, (int)(sizeNeeded * 1.75f)));
for(int r = start, i = size; r < end; r++, i++)
{
items[i] = (short)r;
}
size += end - start;
}
public void addFractionRange (int start, int end, int fraction) {
short[] items = this.items;
int sizeNeeded = size + (end - start) / fraction + 2;
if (sizeNeeded > items.length) items = resize(Math.max(8, (int)(sizeNeeded * 1.75f)));
for(int r = start, i = size; r < end; r = fraction * ((r / fraction) + 1), i++, size++)
{
items[i] = (short) r;
}
}
public short get (int index) {
if (index >= size) throw new IndexOutOfBoundsException("index can't be >= size: " + index + " >= " + size);
return items[index];
}
public void set (int index, short value) {
if (index >= size) throw new IndexOutOfBoundsException("index can't be >= size: " + index + " >= " + size);
items[index] = value;
}
/**
* Adds value to the item in the ShortVLA at index. Calling it "add" would overlap with the collection method.
* @param index
* @param value
*/
public void incr (int index, short value) {
if (index >= size) throw new IndexOutOfBoundsException("index can't be >= size: " + index + " >= " + size);
items[index] += value;
}
public void mul (int index, short value) {
if (index >= size) throw new IndexOutOfBoundsException("index can't be >= size: " + index + " >= " + size);
items[index] *= value;
}
public void insert (int index, short value) {
if (index > size) throw new IndexOutOfBoundsException("index can't be > size: " + index + " > " + size);
short[] items = this.items;
if (size == items.length) items = resize(Math.max(8, (int)(size * 1.75f)));
if (ordered)
System.arraycopy(items, index, items, index + 1, size - index);
else
items[size] = items[index];
size++;
items[index] = value;
}
public void swap (int first, int second) {
if (first >= size) throw new IndexOutOfBoundsException("first can't be >= size: " + first + " >= " + size);
if (second >= size) throw new IndexOutOfBoundsException("second can't be >= size: " + second + " >= " + size);
short[] items = this.items;
short firstValue = items[first];
items[first] = items[second];
items[second] = firstValue;
}
public boolean contains (short value) {
int i = size - 1;
short[] items = this.items;
while (i >= 0)
if (items[i--] == value) return true;
return false;
}
public int indexOf (short value) {
short[] items = this.items;
for (int i = 0, n = size; i < n; i++)
if (items[i] == value) return i;
return -1;
}
public int lastIndexOf (short value) {
short[] items = this.items;
for (int i = size - 1; i >= 0; i--)
if (items[i] == value) return i;
return -1;
}
public boolean removeValue (short value) {
short[] items = this.items;
for (int i = 0, n = size; i < n; i++) {
if (items[i] == value) {
removeIndex(i);
return true;
}
}
return false;
}
/** Removes and returns the item at the specified index. */
public short removeIndex (int index) {
if (index >= size) throw new IndexOutOfBoundsException("index can't be >= size: " + index + " >= " + size);
short[] items = this.items;
short value = items[index];
size--;
if (ordered)
System.arraycopy(items, index + 1, items, index, size - index);
else
items[index] = items[size];
return value;
}
/** Removes the items between the specified indices, inclusive. */
public void removeRange (int start, int end) {
if (end >= size) throw new IndexOutOfBoundsException("end can't be >= size: " + end + " >= " + size);
if (start > end) throw new IndexOutOfBoundsException("start can't be > end: " + start + " > " + end);
short[] items = this.items;
int count = end - start + 1;
if (ordered)
System.arraycopy(items, start + count, items, start, size - (start + count));
else {
int lastIndex = size - 1;
for (int i = 0; i < count; i++)
items[start + i] = items[lastIndex - i];
}
size -= count;
}
/** Removes from this array all of elements contained in the specified array.
* @return true if this array was modified. */
public boolean removeAll (ShortVLA array) {
int size = this.size;
int startSize = size;
short[] items = this.items;
for (int i = 0, n = array.size; i < n; i++) {
short item = array.get(i);
for (int ii = 0; ii < size; ii++) {
if (item == items[ii]) {
removeIndex(ii);
size--;
break;
}
}
}
return size != startSize;
}
/** Removes and returns the last item. */
public short pop () {
return items[--size];
}
/** Returns the last item. */
public short peek () {
return items[size - 1];
}
/** Returns the first item. */
public short first () {
if (size == 0) throw new IllegalStateException("IntVLA is empty.");
return items[0];
}
public void clear () {
size = 0;
}
/** Reduces the size of the backing array to the size of the actual items. This is useful to release memory when many items have
* been removed, or if it is known that more items will not be added.
* @return {@link #items} */
public short[] shrink () {
if (items.length != size) resize(size);
return items;
}
/** Increases the size of the backing array to accommodate the specified number of additional items. Useful before adding many
* items to avoid multiple backing array resizes.
* @return {@link #items} */
public short[] ensureCapacity (int additionalCapacity) {
int sizeNeeded = size + additionalCapacity;
if (sizeNeeded > items.length) resize(Math.max(8, sizeNeeded));
return items;
}
protected short[] resize (int newSize) {
short[] newItems = new short[newSize];
short[] items = this.items;
System.arraycopy(items, 0, newItems, 0, Math.min(size, newItems.length));
this.items = newItems;
return newItems;
}
public int[] asInts () {
int[] newItems = new int[size];
short[] items = this.items;
for (int i = 0; i < size; i++) {
newItems[i] = items[i] & 0xffff;
}
return newItems;
}
public void sort () {
Arrays.sort(items, 0, size);
}
public void reverse () {
short[] items = this.items;
for (int i = 0, lastIndex = size - 1, n = size / 2; i < n; i++) {
int ii = lastIndex - i;
short temp = items[i];
items[i] = items[ii];
items[ii] = temp;
}
}
/** Reduces the size of the array to the specified size. If the array is already smaller than the specified size, no action is
* taken. */
public void truncate (int newSize) {
if (size > newSize) size = newSize;
}
public short[] toArray () {
short[] array = new short[size];
System.arraycopy(items, 0, array, 0, size);
return array;
}
@Override
public int hashCode () {
if (!ordered) return super.hashCode();
short[] items = this.items;
int h = 1;
for (int i = 0, n = size; i < n; i++)
h = h * 31 + items[i];
return h;
}
@Override
public boolean equals (Object object) {
if (object == this) return true;
if (!ordered) return false;
if (!(object instanceof ShortVLA)) return false;
ShortVLA array = (ShortVLA)object;
if (!array.ordered) return false;
int n = size;
if (n != array.size) return false;
for (int i = 0; i < n; i++)
if (items[i] != array.items[i]) return false;
return true;
}
@Override
public String toString () {
if (size == 0) return "[]";
short[] items = this.items;
StringBuilder buffer = new StringBuilder(32);
buffer.append('[')
.append(items[0]);
for (int i = 1; i < size; i++) {
buffer.append(", ")
.append(items[i]);
}
buffer.append(']');
return buffer.toString();
}
public String toString (String separator) {
if (size == 0) return "";
short[] items = this.items;
StringBuilder buffer = new StringBuilder(32);
buffer.append(items[0]);
for (int i = 1; i < size; i++) {
buffer.append(separator)
.append(items[i]);
}
return buffer.toString();
}
/** @see #ShortVLA(short[]) */
public static ShortVLA with (short... array) {
return new ShortVLA(array);
}
}