content: /*
   * Licensed to the Apache Software Foundation (ASF) under one or more
   * contributor license agreements. See the NOTICE file distributed with
   * this work for additional information regarding copyright ownership.
   * The ASF licenses this file to You 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 org.apache.kafka.server.mutable;
  
  import java.util.ArrayList;
  import java.util.Collection;
  import java.util.Collections;
  import java.util.Iterator;
  import java.util.List;
  import java.util.ListIterator;
  
  /**
   * A list which cannot grow beyond a certain length. If the maximum length would be exceeded by an
   * operation, the operation throws a BoundedListTooLongException exception rather than completing.
   * For simplicity, mutation through iterators or sublists is not allowed.
   *
   * @param <E> the element type
   */
  public class BoundedList<E> implements List<E> {
      private final int maxLength;
      private final List<E> underlying;
  
      public static <E> BoundedList<E> newArrayBacked(int maxLength) {
          return new BoundedList<>(maxLength, new ArrayList<>());
      }
  
      public static <E> BoundedList<E> newArrayBacked(int maxLength, int initialCapacity) {
          if (initialCapacity <= 0) {
              throw new IllegalArgumentException("Invalid non-positive initialCapacity of " + initialCapacity);
          }
          return new BoundedList<>(maxLength, new ArrayList<>(initialCapacity));
      }
  
      private BoundedList(int maxLength, List<E> underlying) {
          if (maxLength <= 0) {
              throw new IllegalArgumentException("Invalid non-positive maxLength of " + maxLength);
          }
  
          if (underlying.size() > maxLength) {
              throw new BoundedListTooLongException("Cannot wrap list, because it is longer than " +
                  "the maximum length " + maxLength);
          }
          this.maxLength = maxLength;
          this.underlying = underlying;
      }
  
      @Override
      public int size() {
          return underlying.size();
      }
  
      @Override
      public boolean isEmpty() {
          return underlying.isEmpty();
      }
  
      @Override
      public boolean contains(Object o) {
          return underlying.contains(o);
      }
  
      @Override
      public Iterator<E> iterator() {
          return Collections.unmodifiableList(underlying).iterator();
      }
  
      @Override
      public Object[] toArray() {
          return underlying.toArray();
      }
  
      @Override
      public <T> T[] toArray(T[] a) {
          return underlying.toArray(a);
      }
  
      @Override
      public boolean add(E e) {
          if (underlying.size() >= maxLength) {
              throw new BoundedListTooLongException("Cannot add another element to the list " +
                  "because it would exceed the maximum length of " + maxLength);
          }
          return underlying.add(e);
      }
  
      @Override
      public boolean remove(Object o) {
          return underlying.remove(o);
      }
  
      @Override
      public boolean containsAll(Collection<?> c) {
          return underlying.containsAll(c);
      }
  
      @Override
      public boolean addAll(Collection<? extends E> c) {
          int numToAdd = c.size();
          if (underlying.size() > maxLength - numToAdd) {
              throw new BoundedListTooLongException("Cannot add another " + numToAdd +
                  " element(s) to the list because it would exceed the maximum length of " +
                  maxLength);
          }
          return underlying.addAll(c);
      }
  
      @Override
      public boolean addAll(int index, Collection<? extends E> c) {
          int numToAdd = c.size();
          if (underlying.size() > maxLength - numToAdd) {
              throw new BoundedListTooLongException("Cannot add another " + numToAdd +
                  " element(s) to the list because it would exceed the maximum length of " +
                  maxLength);
          }
          return underlying.addAll(index, c);
      }
  
      @Override
      public boolean removeAll(Collection<?> c) {
          return underlying.removeAll(c);
      }
  
      @Override
      public boolean retainAll(Collection<?> c) {
          return underlying.retainAll(c);
      }
  
      @Override
      public void clear() {
          underlying.clear();
      }
  
      @Override
      public E get(int index) {
          return underlying.get(index);
      }
  
      @Override
      public E set(int index, E element) {
          return underlying.set(index, element);
      }
  
      @Override
      public void add(int index, E element) {
          if (underlying.size() >= maxLength) {
              throw new BoundedListTooLongException("Cannot add another element to the list " +
                      "because it would exceed the maximum length of " + maxLength);
          }
          underlying.add(index, element);
      }
  
      @Override
      public E remove(int index) {
          return underlying.remove(index);
      }
  
      @Override
      public int indexOf(Object o) {
          return underlying.indexOf(o);
      }
  
      @Override
      public int lastIndexOf(Object o) {
          return underlying.lastIndexOf(o);
      }
  
      @Override
      public ListIterator<E> listIterator() {
          return Collections.unmodifiableList(underlying).listIterator();
      }
  
      @Override
      public ListIterator<E> listIterator(int index) {
          return Collections.unmodifiableList(underlying).listIterator(index);
      }
  
      @Override
      public List<E> subList(int fromIndex, int toIndex) {
          return Collections.unmodifiableList(underlying).subList(fromIndex, toIndex);
      }
  
      @Override
      public boolean equals(Object o) {
          return underlying.equals(o);
      }
  
      @Override
      public int hashCode() {
          return underlying.hashCode();
      }
  
      @Override
      public String toString() {
          return underlying.toString();
      }
  }
  