code: protected final void renderAttribute(AbstractRenderAppender buf, String name, String value)
      {
          assert (buf != null) : "Parameter 'buf' must not be null.";
          assert (name != null) : "Parameter 'name' must not be null";
  
          // without a value lets skip writting this out
          if (value == null)
              return;
  
          buf.append(" ");
          buf.append(name);
          buf.append("=\"");
          buf.append(value);
          buf.append("\"");
      }
docs: This method will append an attribute value to a InternalStringBuilder.
  The method assumes that the attr is not <code>null</code>.  If the
  <code>value</code> attribute is <code>null</code> the attribute will not be appended to the
  <code>InternalStringBuilder</code>.
  @param buf   The InternalStringBuilder to append the attribute into.
  @param name  The name of the attribute
  @param value The value of teh attribute.  If this is <code>null</code> the attribute will not be written.