package com.exsoinn.util;
   
   
   import java.util.*;
   
   /**
    * A forwarding {@code Set} which cannot be modified once built.
    *
    * <strong>WARNING:</strong> A malicious/careless client can still extend this class and override the methods that mutate
   *   the object, which in this implementation throw {@link UnsupportedOperationException}. Therefore this class
   *   can at best be considered conditionally thread safe. To provide more robust protection, child classes should be
   *   declared <code>final</code>.
   *
   * Created by QuijadaJ on 5/25/2017.
   */
  public class ForwardingImmutableSet<E> implements Set<E> {
      private final Set<E> list;
  
  
      public ForwardingImmutableSet(Set<? extends E> pSet) {
          list = new HashSet<>(pSet);
      }
  
      @Override
      public int size() {
          return list.size();
      }
  
      @Override
      public boolean isEmpty() {
          return list.isEmpty();
      }
  
      @Override
      public boolean contains(Object o) {
          return list.contains(o);
      }
  
      @Override
      public Iterator<E> iterator() {
          Set<E> newList = new HashSet<>(list);
          return newList.iterator();
      }
  
      @Override
      public Object[] toArray() {
          Set<E> newList = new HashSet<>(list);
          return newList.toArray();
      }
  
      @Override
      public <T> T[] toArray(T[] a) {
          Set<E> newList = new HashSet<>(list);
          return newList.toArray(a);
      }
  
      @Override
      public boolean add(E s) {
          throw new UnsupportedOperationException();
      }
  
      @Override
      public boolean remove(Object o) {
          throw new UnsupportedOperationException();
      }
  
      @Override
      public boolean containsAll(Collection<?> c) {
          return list.containsAll(c);
      }
  
      @Override
      public boolean addAll(Collection<? extends E> c) {
          throw new UnsupportedOperationException();
      }
  
      @Override
      public boolean retainAll(Collection<?> c) {
          throw new UnsupportedOperationException();
      }
  
      @Override
      public boolean removeAll(Collection<?> c) {
          throw new UnsupportedOperationException();
      }
  
      @Override
      public void clear() {
          throw new UnsupportedOperationException();
      }
  
      @Override
      public String toString() {
          return list.toString();
      }
  }