code: public static String extractToString(final DeviceAttribute deviceAttributeRead)
  	    throws DevFailed {
  	final Object value = AttributeHelper.extract(deviceAttributeRead);
  	String argout = null;
  	if (value instanceof Short) {
  	    argout = ((Short) value).toString();
  	} else if (value instanceof String) {
  	    argout = (String) value;
  	} else if (value instanceof Integer) {
  	    argout = ((Integer) value).toString();
  	} else if (value instanceof Long) {
  	    argout = ((Long) value).toString();
  	} else if (value instanceof Float) {
  	    argout = ((Float) value).toString();
  	} else if (value instanceof Boolean) {
  	    argout = ((Boolean) value).toString();
  	} else if (value instanceof Double) {
  	    argout = ((Double) value).toString();
  	} else if (value instanceof DevState) {
  	    argout = StateUtilities.getNameForState((DevState) value);
  	} else {
  	    Except.throw_exception("TANGO_WRONG_DATA_ERROR", "output type " + value.getClass()
  		    + " not supported",
  		    "AttributeHelper.extractToString(Object value,deviceAttributeWritten)");
  	}
  
  	return argout;
      }
docs: Extract data from DeviceAttribute to a String
  
  @param deviceAttributeRead
  the DeviceAttribute attribute to read
  @return String, the result in String format
  @throws DevFailed