137 lines
3.7 KiB
Java
137 lines
3.7 KiB
Java
package queue;
|
|
|
|
import java.util.function.Predicate;
|
|
|
|
/**
|
|
* @author Doschennikov Nikita (me@fymio.us)
|
|
*/
|
|
public class ArrayQueueModule {
|
|
private static Object[] queue = new Object[4];
|
|
private static int head = 0;
|
|
private static int size = 0;
|
|
|
|
public static void enqueue(Object element) {
|
|
assert element != null : "Element must not be null";
|
|
ensureCapacity();
|
|
queue[(head + size) % queue.length] = element;
|
|
size++;
|
|
}
|
|
|
|
public static void push(Object element) {
|
|
assert element != null : "Element must not be null";
|
|
ensureCapacity();
|
|
head = (head - 1 + queue.length) % queue.length;
|
|
queue[head] = element;
|
|
size++;
|
|
}
|
|
|
|
public static Object element() {
|
|
assert size > 0 : "Queue is empty";
|
|
return queue[head];
|
|
}
|
|
|
|
public static Object peek() {
|
|
assert size > 0 : "Queue is empty";
|
|
return queue[(head + size - 1) % queue.length];
|
|
}
|
|
|
|
public static Object dequeue() {
|
|
assert size > 0 : "Queue is empty";
|
|
Object result = queue[head];
|
|
queue[head] = null;
|
|
head = (head + 1) % queue.length;
|
|
size--;
|
|
return result;
|
|
}
|
|
|
|
public static Object remove() {
|
|
assert size > 0 : "Queue is empty";
|
|
int tail = (head + size - 1) % queue.length;
|
|
Object result = queue[tail];
|
|
queue[tail] = null;
|
|
size--;
|
|
return result;
|
|
}
|
|
|
|
public static int size() {
|
|
return size;
|
|
}
|
|
|
|
public static boolean isEmpty() {
|
|
return size == 0;
|
|
}
|
|
|
|
public static void clear() {
|
|
queue = new Object[4];
|
|
head = 0;
|
|
size = 0;
|
|
}
|
|
|
|
public static int count(Object element) {
|
|
assert element != null : "Element must not be null";
|
|
int cnt = 0;
|
|
for (int i = 0; i < size; i++) {
|
|
if (element.equals(queue[(head + i) % queue.length])) {
|
|
cnt++;
|
|
}
|
|
}
|
|
return cnt;
|
|
}
|
|
|
|
public static int countIf(Predicate<Object> predicate) {
|
|
assert predicate != null : "Predicate must not be null";
|
|
int cnt = 0;
|
|
for (int i = 0; i < size; i++) {
|
|
if (predicate.test(queue[(head + i) % queue.length])) {
|
|
cnt++;
|
|
}
|
|
}
|
|
return cnt;
|
|
}
|
|
|
|
public static int indexIf(Predicate<Object> predicate) {
|
|
assert predicate != null : "Predicate must not be null";
|
|
for (int i = 0; i < size; i++) {
|
|
if (predicate.test(queue[(head + i) % queue.length])) {
|
|
return i;
|
|
}
|
|
}
|
|
return -1;
|
|
}
|
|
|
|
public static int lastIndexIf(Predicate<Object> predicate) {
|
|
assert predicate != null : "Predicate must not be null";
|
|
for (int i = size - 1; i >= 0; i--) {
|
|
if (predicate.test(queue[(head + i) % queue.length])) {
|
|
return i;
|
|
}
|
|
}
|
|
return -1;
|
|
}
|
|
|
|
public static int indexOf(Object element) {
|
|
assert element != null : "Predicate must not be null";
|
|
for (int i = 0; i < size; i++) {
|
|
if (queue[(head + i) % queue.length].equals(element)) return i;
|
|
}
|
|
return -1;
|
|
}
|
|
|
|
public static int lastIndexOf(Object element) {
|
|
assert element != null : "Predicate must not be null";
|
|
for (int i = size - 1; i >= 0; i--) {
|
|
if (queue[(head + i) % queue.length].equals(element)) return i;
|
|
}
|
|
return -1;
|
|
}
|
|
|
|
private static void ensureCapacity() {
|
|
if (size < queue.length) return;
|
|
Object[] newQueue = new Object[queue.length * 2];
|
|
for (int i = 0; i < size; i++) {
|
|
newQueue[i] = queue[(head + i) % queue.length];
|
|
}
|
|
queue = newQueue;
|
|
head = 0;
|
|
}
|
|
} |