code: public Object getValue(ELContext context,
                             Object base,
                             Object property) {
  
          if (context == null) {
              throw new NullPointerException();
          }
  
          if (base != null && base instanceof List) {
              context.setPropertyResolved(base, property);
              List list = (List) base;
              int index = toInteger(property);
              if (index < 0 || index >= list.size()) {
                  return null;
              } 
              return list.get(index);
          }
          return null;
      }
docs: If the base object is a list, returns the value at the given index.
  The index is specified by the <code>property</code> argument, and
  coerced into an integer. If the coercion could not be performed,
  an <code>IllegalArgumentException</code> is thrown. If the index is
  out of bounds, <code>null</code> is returned.
  
  <p>If the base is a <code>List</code>, the <code>propertyResolved</code>
  property of the <code>ELContext</code> object must be set to
  <code>true</code> by this resolver, before returning. If this property
  is not <code>true</code> after this method is called, the caller
  should ignore the return value.</p>
  
  @param context The context of this evaluation.
  @param base The list to be analyzed. Only bases of type
  <code>List</code> are handled by this resolver.
  @param property The index of the value to be returned. Will be coerced
  into an integer.
  @return If the <code>propertyResolved</code> property of
  <code>ELContext</code> was set to <code>true</code>, then
  the value at the given index or <code>null</code>
  if the index was out of bounds. Otherwise, undefined.
  @throws IllegalArgumentException if the property could not be coerced
  into an integer.
  @throws NullPointerException if context is <code>null</code>.
  @throws ELException if an exception was thrown while performing
  the property or variable resolution. The thrown exception
  must be included as the cause property of this exception, if
  available.