Set接口源码解析

Set
无须集合
元素不可以重复
接口内源码和上面其他接口很类似

package java.util;

public interface Set<E> extends Collection<E> {

    int size();

    boolean isEmpty();

    boolean contains(Object o);

    Iterator<E> iterator();

    Object[] toArray();

    <T> T[] toArray(T[] a);

    boolean add(E e);

    boolean remove(Object o);

    boolean containsAll(Collection<?> c);

    boolean addAll(Collection<? extends E> c);

    boolean retainAll(Collection<?> c);

    boolean removeAll(Collection<?> c);

    void clear();

    boolean equals(Object o);

    int hashCode();
}