dorkbox.util.collections.IntArray Maven / Gradle / Ivy
Go to download
Show more of this group Show more artifacts with this name
Show all versions of Network-Dorkbox-Util Show documentation
Show all versions of Network-Dorkbox-Util Show documentation
Utilities for the Network project.
The newest version!
/*******************************************************************************
* Copyright 2010 Mario Zechner ([email protected]), Nathan Sweet ([email protected])
*
* 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.
*/
// from libGDX
package dorkbox.util.collections;
import dorkbox.util.MathUtil;
import java.util.Arrays;
/** A resizable, ordered or unordered int array. Avoids the boxing that occurs with ArrayList. 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;
this.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;
this.size = array.size;
this.items = new int[this.size];
System.arraycopy(array.items, 0, this.items, 0, this.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, 0, 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 IntArray (boolean ordered, int[] array, int startIndex, int count) {
this(ordered, array.length);
this.size = count;
System.arraycopy(array, startIndex, this.items, 0, count);
}
public void add (int value) {
int[] items = this.items;
if (this.size == items.length) {
items = resize(Math.max(8, (int)(this.size * 1.75f)));
}
items[this.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 = this.size + length;
if (sizeNeeded >= items.length) {
items = resize(Math.max(8, (int)(sizeNeeded * 1.75f)));
}
System.arraycopy(array, offset, items, this.size, length);
this.size += length;
}
public int get (int index) {
if (index >= this.size) {
throw new IndexOutOfBoundsException(String.valueOf(index));
}
return this.items[index];
}
public void set (int index, int value) {
if (index >= this.size) {
throw new IndexOutOfBoundsException(String.valueOf(index));
}
this.items[index] = value;
}
public void insert (int index, int value) {
if (index > this.size) {
throw new IndexOutOfBoundsException(String.valueOf(index));
}
int[] items = this.items;
if (this.size == items.length) {
items = resize(Math.max(8, (int)(this.size * 1.75f)));
}
if (this.ordered) {
System.arraycopy(items, index, items, index + 1, this.size - index);
} else {
items[this.size] = items[index];
}
this.size++;
items[index] = value;
}
public void swap (int first, int second) {
if (first >= this.size) {
throw new IndexOutOfBoundsException(String.valueOf(first));
}
if (second >= this.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 = this.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 = this.size; i < n; i++) {
if (items[i] == value) {
return i;
}
}
return -1;
}
public int lastIndexOf (int value) {
int[] items = this.items;
for (int i = this.size - 1; i >= 0; i--) {
if (items[i] == value) {
return i;
}
}
return -1;
}
public boolean removeValue (int value) {
int[] items = this.items;
for (int i = 0, n = this.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 >= this.size) {
throw new IndexOutOfBoundsException(String.valueOf(index));
}
int[] items = this.items;
int value = items[index];
this.size--;
if (this.ordered) {
System.arraycopy(items, index + 1, items, index, this.size - index);
} else {
items[index] = items[this.size];
}
return value;
}
/** Removes from this array all of elements contained in the specified array.
* @return true if this array was modified. */
public boolean removeAll (IntArray array) {
int size = this.size;
int startSize = size;
int[] items = this.items;
for (int i = 0, n = array.size; i < n; i++) {
int 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 int pop () {
return this.items[--this.size];
}
/** Returns the last item. */
public int peek () {
return this.items[this.size - 1];
}
/** Returns the first item. */
public int first () {
if (this.size == 0) {
throw new IllegalStateException("Array is empty.");
}
return this.items[0];
}
public void clear () {
this.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(this.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 = this.size + additionalCapacity;
if (sizeNeeded >= this.items.length) {
resize(Math.max(8, sizeNeeded));
}
return this.items;
}
protected int[] resize (int newSize) {
int[] newItems = new int[newSize];
int[] items = this.items;
System.arraycopy(items, 0, newItems, 0, Math.min(this.size, newItems.length));
this.items = newItems;
return newItems;
}
public void sort () {
Arrays.sort(this.items, 0, this.size);
}
public void reverse () {
for (int i = 0, lastIndex = this.size - 1, n = this.size / 2; i < n; i++) {
int ii = lastIndex - i;
int temp = this.items[i];
this.items[i] = this.items[ii];
this.items[ii] = temp;
}
}
public void shuffle () {
for (int i = this.size - 1; i >= 0; i--) {
int ii = MathUtil.randomInt(i);
int temp = this.items[i];
this.items[i] = this.items[ii];
this.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 (this.size > newSize) {
this.size = newSize;
}
}
/** Returns a random item from the array, or zero if the array is empty. */
public int random () {
if (this.size == 0) {
return 0;
}
return this.items[MathUtil.randomInt(0, this.size - 1)];
}
public int[] toArray () {
int[] array = new int[this.size];
System.arraycopy(this.items, 0, array, 0, this.size);
return array;
}
@Override
public int hashCode() {
final int prime = 31;
int result = 1;
result = prime * result + Arrays.hashCode(this.items);
result = prime * result + (this.ordered ? 1231 : 1237);
result = prime * result + this.size;
return result;
}
@Override
public boolean equals (Object object) {
if (object == this) {
return true;
}
if (!(object instanceof IntArray)) {
return false;
}
IntArray array = (IntArray)object;
int n = this.size;
if (n != array.size) {
return false;
}
for (int i = 0; i < n; i++) {
if (this.items[i] != array.items[i]) {
return false;
}
}
return true;
}
@Override
public String toString () {
if (this.size == 0) {
return "[]";
}
int[] items = this.items;
StringBuilder buffer = new StringBuilder(32);
buffer.append('[');
buffer.append(items[0]);
for (int i = 1; i < this.size; i++) {
buffer.append(", ");
buffer.append(items[i]);
}
buffer.append(']');
return buffer.toString();
}
public String toString (String separator) {
if (this.size == 0) {
return "";
}
int[] items = this.items;
StringBuilder buffer = new StringBuilder(32);
buffer.append(items[0]);
for (int i = 1; i < this.size; i++) {
buffer.append(separator);
buffer.append(items[i]);
}
return buffer.toString();
}
}
© 2015 - 2025 Weber Informatics LLC | Privacy Policy