org.antlr.v4.runtime.misc.IntegerList Maven / Gradle / Ivy
/*
* Copyright (c) 2012 The ANTLR Project. All rights reserved.
* Use of this file is governed by the BSD-3-Clause license that
* can be found in the LICENSE.txt file in the project root.
*/
package org.antlr.v4.runtime.misc;
import java.util.Arrays;
import java.util.Collection;
import java.util.List;
/**
*
* @author Sam Harwell
*/
public class IntegerList {
private static int[] EMPTY_DATA = new int[0];
private static final int INITIAL_SIZE = 4;
private static final int MAX_ARRAY_SIZE = Integer.MAX_VALUE - 8;
@NotNull
private int[] _data;
private int _size;
public IntegerList() {
_data = EMPTY_DATA;
}
public IntegerList(int capacity) {
if (capacity < 0) {
throw new IllegalArgumentException();
}
if (capacity == 0) {
_data = EMPTY_DATA;
}
else {
_data = new int[capacity];
}
}
public IntegerList(@NotNull IntegerList list) {
_data = list._data.clone();
_size = list._size;
}
public IntegerList(@NotNull Collection list) {
this(list.size());
for (Integer value : list) {
add(value);
}
}
public final void add(int value) {
if (_data.length == _size) {
ensureCapacity(_size + 1);
}
_data[_size] = value;
_size++;
}
public final void addAll(int[] array) {
ensureCapacity(_size + array.length);
System.arraycopy(array, 0, _data, _size, array.length);
_size += array.length;
}
public final void addAll(IntegerList list) {
ensureCapacity(_size + list._size);
System.arraycopy(list._data, 0, _data, _size, list._size);
_size += list._size;
}
public final void addAll(Collection list) {
ensureCapacity(_size + list.size());
int current = 0;
for (int x : list) {
_data[_size + current] = x;
current++;
}
_size += list.size();
}
public final int get(int index) {
if (index < 0 || index >= _size) {
throw new IndexOutOfBoundsException();
}
return _data[index];
}
public final boolean contains(int value) {
for (int i = 0; i < _size; i++) {
if (_data[i] == value) {
return true;
}
}
return false;
}
public final int set(int index, int value) {
if (index < 0 || index >= _size) {
throw new IndexOutOfBoundsException();
}
int previous = _data[index];
_data[index] = value;
return previous;
}
public final int removeAt(int index) {
int value = get(index);
System.arraycopy(_data, index + 1, _data, index, _size - index - 1);
_data[_size - 1] = 0;
_size--;
return value;
}
public final void removeRange(int fromIndex, int toIndex) {
if (fromIndex < 0 || toIndex < 0 || fromIndex > _size || toIndex > _size) {
throw new IndexOutOfBoundsException();
}
if (fromIndex > toIndex) {
throw new IllegalArgumentException();
}
System.arraycopy(_data, toIndex, _data, fromIndex, _size - toIndex);
Arrays.fill(_data, _size - (toIndex - fromIndex), _size, 0);
_size -= (toIndex - fromIndex);
}
public final boolean isEmpty() {
return _size == 0;
}
public final int size() {
return _size;
}
public final void trimToSize() {
if (_data.length == _size) {
return;
}
_data = Arrays.copyOf(_data, _size);
}
public final void clear() {
Arrays.fill(_data, 0, _size, 0);
_size = 0;
}
public final int[] toArray() {
if (_size == 0) {
return EMPTY_DATA;
}
return Arrays.copyOf(_data, _size);
}
public final void sort() {
Arrays.sort(_data, 0, _size);
}
/**
* Compares the specified object with this list for equality. Returns
* {@code true} if and only if the specified object is also an {@link IntegerList},
* both lists have the same size, and all corresponding pairs of elements in
* the two lists are equal. In other words, two lists are defined to be
* equal if they contain the same elements in the same order.
*
* This implementation first checks if the specified object is this
* list. If so, it returns {@code true}; if not, it checks if the
* specified object is an {@link IntegerList}. If not, it returns {@code false};
* if so, it checks the size of both lists. If the lists are not the same size,
* it returns {@code false}; otherwise it iterates over both lists, comparing
* corresponding pairs of elements. If any comparison returns {@code false},
* this method returns {@code false}.
*
* @param o the object to be compared for equality with this list
* @return {@code true} if the specified object is equal to this list
*/
@Override
public boolean equals(Object o) {
if (o == this) {
return true;
}
if (!(o instanceof IntegerList)) {
return false;
}
IntegerList other = (IntegerList)o;
if (_size != other._size) {
return false;
}
for (int i = 0; i < _size; i++) {
if (_data[i] != other._data[i]) {
return false;
}
}
return true;
}
/**
* Returns the hash code value for this list.
*
*
This implementation uses exactly the code that is used to define the
* list hash function in the documentation for the {@link List#hashCode}
* method.
*
* @return the hash code value for this list
*/
@Override
public int hashCode() {
int hashCode = 1;
for (int i = 0; i < _size; i++) {
hashCode = 31*hashCode + _data[i];
}
return hashCode;
}
/**
* Returns a string representation of this list.
*/
@Override
public String toString() {
return Arrays.toString(toArray());
}
public final int binarySearch(int key) {
return Arrays.binarySearch(_data, 0, _size, key);
}
public final int binarySearch(int fromIndex, int toIndex, int key) {
if (fromIndex < 0 || toIndex < 0 || fromIndex > _size || toIndex > _size) {
throw new IndexOutOfBoundsException();
}
if (fromIndex > toIndex) {
throw new IllegalArgumentException();
}
return Arrays.binarySearch(_data, fromIndex, toIndex, key);
}
private void ensureCapacity(int capacity) {
if (capacity < 0 || capacity > MAX_ARRAY_SIZE) {
throw new OutOfMemoryError();
}
int newLength;
if (_data.length == 0) {
newLength = INITIAL_SIZE;
}
else {
newLength = _data.length;
}
while (newLength < capacity) {
newLength = newLength * 2;
if (newLength < 0 || newLength > MAX_ARRAY_SIZE) {
newLength = MAX_ARRAY_SIZE;
}
}
_data = Arrays.copyOf(_data, newLength);
}
}