Re: [Htmlparser-developer] Method to check if TextNode is just whitespace

[Derrick O. <Der...@Ro...>]

IMHO, the text shouldn't ever be null, but if it is, toHtml() would 
(should?) return an empty string, so isWhitespace() should also return true.

Ian Macfarlane wrote:

>>Conversion of character references like   is already performed by the util.Translate class.
>>    
>>
>Oh good! No need for me to write it then :)
>
>  
>
>>There is no &tab; character reference as far as I'm aware
>>    
>>
>You're right, I just guessed a whitespace entity name, typed it into
>Google and found references to it. Sorry, I ought to have checked it
>out a bit better first.
>
>Derrick, for a isWhiteSpace() method, what do you think it ought to do
>when the String is null?
>
>Ian
>
>On 11/3/05, Derrick Oswald <Der...@ro...> wrote:
>  
>
>>Conversion of character references like &nbsp; is already performed by
>>the util.Translate class.
>>There is no &tab; character reference as far as I'm aware (see
>>http://www.w3.org/TR/REC-html40/sgml/entities.html).
>>
>>Ian Macfarlane wrote:
>>
>>    
>>
>>>Thanks for your reply,
>>>
>>>I wasn't suggesting trimming the actual text of the text nodes
>>>permanently, merely wondering if using the trim() method to see if the
>>>resulting string was empty would be sufficient, or whether we should
>>>also look for various white-space HTML entities (e.g. &tab; also) for
>>>purposes of determining this.
>>>
>>>Now I think about it some more, white space alone is probably what we
>>>want to do. If we want to get things like &tab; we ought to write some
>>>sort of method that would replace those types of HTML character
>>>references with the actual characters, if that's feasible.
>>>
>>>The only other question I've got - what do you all think should happen
>>>if the contents of the text node is null? Should it return true
>>>(because there's no characters), false (because it's not actually a
>>>white space String) or throw a NullPointerException (which would
>>>negate the value of this method by forcing the end-user to write lots
>>>of code to use this method)? Can a text node ever be null without the
>>>user changing the text ot be null?
>>>
>>>Ian
>>>
>>>String is immutable so String.trim().equals("") won't change the
>>>original String object.
>>>
>>>On 11/2/05, Axel <ax...@gm...> wrote:
>>>
>>>
>>>      
>>>
>>>>On 11/1/05, Ian Macfarlane <ian...@gm...> wrote:
>>>>
>>>>
>>>>        
>>>>
>>>>>I was thinking it might be worthwhile adding a method to Text/TextNode
>>>>>along the lines of:
>>>>>
>>>>>boolean isWhiteSpace()
>>>>>
>>>>>Which would return if the TextNode consisted of solely white space
>>>>>characters (or was the empty String).
>>>>>
>>>>>Now this could simply be done using String.trim().equals(""), however
>>>>>that wouldn't account for:
>>>>>
>>>>>- the non-breaking space character (#160)
>>>>>- The HTML code &nbsp; (also &nbsp as Firefox/IE do)
>>>>>- The HTML code &#160; (also &#160 as Firefox/IE do)
>>>>>
>>>>>So my question is, do you think should this method should treat those
>>>>>as spaces and remove/ignore them also for purposes of determining if
>>>>>the TextNode is white space? Or should it only trim normal whitespace
>>>>>(space, tab, carriage returns, etc).
>>>>>
>>>>>
>>>>>          
>>>>>
>>>>I think, if every character (or entity converted to a
>>>>unicode-character) in the TextNode is true for
>>>>Character#isWhitespace() the boolean isWhiteSpace() should return
>>>>true;
>>>>IMO the TextNode shouldn't be trimmed automatically. Only a special
>>>>function should allow this to do.
>>>>
>>>>--
>>>>Axel Kramer
>>>>http://www.plog4u.org - Wikipedia Eclipse Plugin
>>>>
>>>>
>>>>-------------------------------------------------------
>>>>SF.Net email is sponsored by:
>>>>Tame your development challenges with Apache's Geronimo App Server. Download
>>>>it for free - -and be entered to win a 42" plasma tv or your very own
>>>>Sony(tm)PSP.  Click here to play: http://sourceforge.net/geronimo.php
>>>>_______________________________________________
>>>>Htmlparser-developer mailing list
>>>>Htm...@li...
>>>>https://lists.sourceforge.net/lists/listinfo/htmlparser-developer
>>>>
>>>>
>>>>
>>>>        
>>>>
>>>-------------------------------------------------------
>>>SF.Net email is sponsored by:
>>>Tame your development challenges with Apache's Geronimo App Server. Download
>>>it for free - -and be entered to win a 42" plasma tv or your very own
>>>Sony(tm)PSP.  Click here to play: http://sourceforge.net/geronimo.php
>>>_______________________________________________
>>>Htmlparser-developer mailing list
>>>Htm...@li...
>>>https://lists.sourceforge.net/lists/listinfo/htmlparser-developer
>>>
>>>
>>>
>>>      
>>>
>>
>>-------------------------------------------------------
>>SF.Net email is sponsored by:
>>Tame your development challenges with Apache's Geronimo App Server. Download
>>it for free - -and be entered to win a 42" plasma tv or your very own
>>Sony(tm)PSP.  Click here to play: http://sourceforge.net/geronimo.php
>>_______________________________________________
>>Htmlparser-developer mailing list
>>Htm...@li...
>>https://lists.sourceforge.net/lists/listinfo/htmlparser-developer
>>
>>    
>>
>
>
>-------------------------------------------------------
>SF.Net email is sponsored by:
>Tame your development challenges with Apache's Geronimo App Server. Download
>it for free - -and be entered to win a 42" plasma tv or your very own
>Sony(tm)PSP.  Click here to play: http://sourceforge.net/geronimo.php
>_______________________________________________
>Htmlparser-developer mailing list
>Htm...@li...
>https://lists.sourceforge.net/lists/listinfo/htmlparser-developer
>
>  
>