code: public IntBuffer getIntVec(String attributeName)
      {
          int size = getAttributeSize(attributeName);
          if (size <= 0)
          {
              return null;
          }
          size *= 4 * getVertexCount();
          ByteBuffer buffer = ByteBuffer.allocateDirect(size).order(ByteOrder.nativeOrder());
          IntBuffer data = buffer.asIntBuffer();
          if (!NativeVertexBuffer.getIntVec(getNative(), attributeName, data, 0, 0))
          {
              throw new IllegalArgumentException("Attribute name " + attributeName + " cannot be accessed");
          }
          return data;
      }
docs: Retrieves a vertex attribute as an integer buffer.
  The attribute name must be one of the
  attributes named in the descriptor passed to the constructor.
  @param attributeName name of the attribute to update
  @throws IllegalArgumentException if attribute name not in descriptor vertex attribute is not <i>int</i>
  @see #setIntArray(String, int[])
  @see #getIntVec(String)