code: public double optDouble(String key){
  		LazyNode token=getOptionalFieldToken(key);
  		if(token==null)return 0.0;
  		if(token.type==LazyNode.VALUE_NULL)return 0.0;
  		return token.getDoubleValue();
  	}
docs: Returns the double value stored in this object for the given key.
  Returns 0.0 if there is no such key.
  
  @param key the name of the field on this object
  @return the requested double value or 0.0 if there was no such key