package com.esotericsoftware.kryo.util;
import java.util.Arrays;
/** A resizable, ordered or unordered int array. Avoids the boxing that occurs with ArrayList<Integer>. If unordered, this class
* avoids a memory copy when removing elements (the last element is moved to the removed element's position).
* @author Nathan Sweet */
public class IntArray {
public int[] items;
public int size;
public boolean ordered;
/** Creates an ordered array with a capacity of 16. */
public IntArray () {
this(true, 16);
}
/** Creates an ordered array with the specified capacity. */
public IntArray (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 IntArray (boolean ordered, int capacity) {
this.ordered = ordered;
items = new int[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 IntArray (IntArray array) {
this.ordered = array.ordered;
size = array.size;
items = new int[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 IntArray (int[] array) {
this(true, array);
}
/** 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 IntArray (boolean ordered, int[] array) {
this(ordered, array.length);
size = array.length;
System.arraycopy(array, 0, items, 0, size);
}
public void add (int value) {
int[] items = this.items;
if (size == items.length) items = resize(Math.max(8, (int)(size * 1.75f)));
items[size++] = value;
}
public void addAll (IntArray array) {
addAll(array, 0, array.size);
}
public void addAll (IntArray 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 (int[] array) {
addAll(array, 0, array.length);
}
public void addAll (int[] array, int offset, int length) {
int[] items = this.items;
int sizeNeeded = size + length - offset;
if (sizeNeeded >= items.length) items = resize(Math.max(8, (int)(sizeNeeded * 1.75f)));
System.arraycopy(array, offset, items, size, length);
size += length;
}
public int get (int index) {
if (index >= size) throw new IndexOutOfBoundsException(String.valueOf(index));
return items[index];
}
public void set (int index, int value) {
if (index >= size) throw new IndexOutOfBoundsException(String.valueOf(index));
items[index] = value;
}
public void insert (int index, int value) {
int[] 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(String.valueOf(first));
if (second >= size) throw new IndexOutOfBoundsException(String.valueOf(second));
int[] items = this.items;
int firstValue = items[first];
items[first] = items[second];
items[second] = firstValue;
}
public boolean contains (int value) {
int i = size - 1;
int[] items = this.items;
while (i >= 0)
if (items[i--] == value) return true;
return false;
}
public int indexOf (int value) {
int[] items = this.items;
for (int i = 0, n = size; i < n; i++)
if (items[i] == value) return i;
return -1;
}
public boolean removeValue (int value) {
int[] 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 int removeIndex (int index) {
if (index >= size) throw new IndexOutOfBoundsException(String.valueOf(index));
int[] items = this.items;
int value = items[index];
size--;
if (ordered)
System.arraycopy(items, index + 1, items, index, size - index);
else
items[index] = items[size];
return value;
}
/** Removes and returns the last item. */
public int pop () {
return items[--size];
}
/** Returns the last item. */
public int peek () {
return items[size - 1];
}
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. */
public void shrink () {
resize(size);
}
/** Increases the size of the backing array to acommodate the specified number of additional items. Useful before adding many
* items to avoid multiple backing array resizes.
* @return {@link #items} */
public int[] ensureCapacity (int additionalCapacity) {
int sizeNeeded = size + additionalCapacity;
if (sizeNeeded >= items.length) resize(Math.max(8, sizeNeeded));
return items;
}
protected int[] resize (int newSize) {
int[] newItems = new int[newSize];
int[] items = this.items;
System.arraycopy(items, 0, newItems, 0, Math.min(items.length, newItems.length));
this.items = newItems;
return newItems;
}
public void sort () {
Arrays.sort(items, 0, size);
}
public void reverse () {
for (int i = 0, lastIndex = size - 1, n = size / 2; i < n; i++) {
int ii = lastIndex - i;
int 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 int[] toArray () {
int[] array = new int[size];
System.arraycopy(items, 0, array, 0, size);
return array;
}
public String toString () {
if (size == 0) return "[]";
int[] items = this.items;
StringBuilder buffer = new StringBuilder(32);
buffer.append('[');
buffer.append(items[0]);
for (int i = 1; i < size; i++) {
buffer.append(", ");
buffer.append(items[i]);
}
buffer.append(']');
return buffer.toString();
}
public String toString (String separator) {
if (size == 0) return "";
int[] items = this.items;
StringBuilder buffer = new StringBuilder(32);
buffer.append(items[0]);
for (int i = 1; i < size; i++) {
buffer.append(separator);
buffer.append(items[i]);
}
return buffer.toString();
}
}