/*
* Copyright (c) MuleSoft, Inc. All rights reserved. http://www.mulesoft.com
* The software in this package is published under the terms of the CPAL v1.0
* license, a copy of which has been included with this distribution in the
* LICENSE.txt file.
*/
package org.mule.runtime.core.internal.streaming.object;
import static java.util.Optional.empty;
import static java.util.Optional.ofNullable;
import java.util.ArrayList;
import java.util.List;
import java.util.Optional;
/**
* A zero-based indexed group of items.
* <p>
* Buckets have a fixed capacity. Once reached, the bucket will accept no more items
*
* @param <T> the generic type of the items
* @since 4.0
*/
public class Bucket<T> {
private final List<T> items;
private final int capacity;
private final int index;
/**
* Creates a new instance
*
* @param index the bucket's index.
* @param capacity the bucket's capacity.
*/
public Bucket(int index, int capacity) {
this.index = index;
this.capacity = capacity;
this.items = new ArrayList<>(capacity);
}
/**
* Obtains the value that was added at the given {@code index} through the {@link #add(Object)} method.
* If no such value was added, it will return an empty value.
*
* @param index the item's index
* @return an {@link Optional} value
*/
public Optional<T> get(int index) {
if (index < items.size()) {
return ofNullable(items.get(index));
}
return empty();
}
/**
* @param position a {@link Position}
* @return Whether this bucket contains an item for the given {@code position}
*/
public boolean contains(Position position) {
return index == position.getBucketIndex() && position.getItemIndex() < items.size();
}
/**
* @return {@code this} bucket's index
*/
public int getIndex() {
return index;
}
/**
* Adds the given {@code item} if the bucket still has capacity.
*
* @param item the item to be added
* @return whether the item was accepted or not
*/
public boolean add(T item) {
if (items.size() < capacity) {
items.add(item);
return true;
}
return false;
}
}