code: public String readClass(final int index, final char[] buf) {
          // computes the start index of the CONSTANT_Class item in b
          // and reads the CONSTANT_Utf8 item designated by
          // the first two bytes of this CONSTANT_Class item
          String name = readUTF8(items[readUnsignedShort(index)], buf);
          return (name != null ? name.intern() : null);
      }
docs: Reads a class constant pool item in {@link #b b}. <i>This method is
  intended for {@link Attribute} sub classes, and is normally not needed by
  class generators or adapters.</i>
  
  @param index
  the start index of an unsigned short value in {@link #b b},
  whose value is the index of a class constant pool item.
  @param buf
  buffer to be used to read the item. This buffer must be
  sufficiently large. It is not automatically resized.
  @return the String corresponding to the specified class item.