Class AbstractCollection

classpath/java/util/AbstractCollection.java:17–108

@author zsombor

 * 
 */
public abstract class AbstractCollection<T> implements Collection<T> {
  public boolean add(T element) {
    throw new UnsupportedOperationException("adding to "
                                            + this.getClass().getName());
  }

  public boolean addAll(Collection<? extends T> collection) {
    boolean result = false;
    for (T obj : collection) {
      result |= add(obj);
    }
    return result;
  }

  public void clear() {
    throw new UnsupportedOperationException("clear() in "
                                            + this.getClass().getName());
  }

  public boolean contains(Object element) {
    if (element != null) {
      for (Iterator<T> iter = iterator(); iter.hasNext();) {
        if (element.equals(iter.next())) {
          return true;
        }
      }
    } else {
      for (Iterator<T> iter = iterator(); iter.hasNext();) {
        if (iter.next()==null) {
          return true;
        }
      }
                        
    }
    return false;
  }

  public boolean containsAll(Collection<?> c) {
    if (c == null) {
      throw new NullPointerException("Collection is null");
    }

    Iterator<?> it = c.iterator();
    while (it.hasNext()) {
      if (! contains(it.next())) {
        return false;
      }
    }

    return true;
  }

  public boolean isEmpty() {
    return size() == 0;
  }

  public boolean remove(Object element) {
    throw new UnsupportedOperationException("remove(T) in "