hu.akarnokd.rxjava2.internal.util.AppendOnlyLinkedArrayList Maven / Gradle / Ivy
Show all versions of rxjava2-backport Show documentation
/**
* Copyright 2015 David Karnok and Netflix, Inc.
*
* 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 hu.akarnokd.rxjava2.internal.util;
import hu.akarnokd.rxjava2.functions.*;
/**
* A linked-array-list implementation that only supports appending and consumption.
*
* @param the value type
*/
public class AppendOnlyLinkedArrayList {
final int capacity;
Object[] head;
Object[] tail;
int offset;
/**
* Constructs an empty list with a per-link capacity
* @param capacity the capacity of each link
*/
public AppendOnlyLinkedArrayList(int capacity) {
this.capacity = capacity;
this.head = new Object[capacity + 1];
this.tail = head;
}
/**
* Append a non-null value to the list.
* Don't add null to the list!
* @param value the value to append
*/
public void add(T value) {
final int c = capacity;
int o = offset;
if (o == c) {
Object[] next = new Object[c + 1];
tail[c] = next;
tail = next;
o = 0;
}
tail[o] = value;
offset = o + 1;
}
/**
* Set a value as the first element of the list.
* @param value the value to set
*/
public void setFirst(T value) {
head[0] = value;
}
/**
* Loops through all elements of the list.
* @param consumer the consumer of elements
*/
@SuppressWarnings("unchecked")
public void forEach(Consumer consumer) {
Object[] a = head;
final int c = capacity;
while (a != null) {
for (int i = 0; i < c; i++) {
Object o = a[i];
if (o == null) {
return;
}
consumer.accept((T)o);
}
a = (Object[])a[c];
}
}
/**
* Loops over all elements of the array until a null element is encountered or
* the given predicate returns true.
* @param consumer the consumer of values that returns true if the forEach should terminate
*/
@SuppressWarnings("unchecked")
public void forEachWhile(Predicate consumer) {
Object[] a = head;
final int c = capacity;
while (a != null) {
for (int i = 0; i < c; i++) {
Object o = a[i];
if (o == null) {
return;
}
if (consumer.test((T)o)) {
return;
}
}
a = (Object[])a[c];
}
}
@SuppressWarnings("unchecked")
public void forEachWhile(S state, BiPredicate consumer) {
Object[] a = head;
final int c = capacity;
while (a != null) {
for (int i = 0; i < c; i++) {
Object o = a[i];
if (o == null) {
return;
}
if (consumer.test(state, (T)o)) {
return;
}
}
a = (Object[])a[c];
}
}
}