@Override
  public boolean contains(Object o) {
    return indexOf(o) >= 0;
  }
Returns <tt>true</tt> if this list contains the specified element. More formally, returns
<tt>true</tt> if and only if this list contains at least one element <tt>e</tt> such that
<tt>(o==null&nbsp;?&nbsp;e==null&nbsp;:&nbsp;o.equals(e))</tt>.

@param o element whose presence in this list is to be tested
@return <tt>true</tt> if this list contains the specified element
geode-core/src/main/java/org/apache/geode/cache/query/internal/index/IndexElemArray.java