B4A Library JTidy library - Convert HTML pages to XML

This library wraps JTidy open source project.
It is supported by B4A and B4J.

It allows you to convert a HTML page to XHTML page. XHTML can be parsed with a XML parser.

This approach is better than trying to parse HTML with regular expressions.

Usage is simple:

Sub Process_Globals
   Dim sax As SaxParser
   Dim tid As Tidy
End Sub

Sub Activity_Create(FirstTime As Boolean)
   tid.Initialize
   'parse the Html page and create a new xml document.
   tid.Parse(File.OpenInput(File.DirAssets, "index.html"), File.DirRootExternal, "1.xml")
   sax.Initialize
   sax.Parse(File.OpenInput(File.DirRootExternal, "1.xml"), "sax")
End Sub

Tips: By default jTidy will not output anything if it encounter an error. You can see the errors in the unfiltered logs.

You can force it to always make output with:

tid.Initialize
Dim jo As JavaObject = tid
jo.GetFieldJO("tidy").RunMethod("setForceOutput", Array(True))

If parsing of the generated document is very slow then follow this post: https://www.b4x.com/android/forum/t...seems-very-slow-long-delay.91627/#post-578641

 

[NJDude]

This lib should be added to the Extras or Internal libraries directory?

I'm asking to keep the "official" libs where they belong in case of a B4A upgrade.

Thanks

 

[Erel]

You can add it to any one of these folders. Libraries that are based on open source projects are usually not distributed together with the IDE so it doesn't matter.

 

[NJDude]

Thank you.

 

[Inman]

Great news. Coming from VB with DOM parser, HTML parsing had been always an issue for me on B4A.

Not any more!

 

[walterf25]

Quick question about jtidy

Hello Erel and NJ, i was giving this library a try, i need to update one of my apps and thought i would use this library to make the parsing a little faster, anyhow i gave it a go but when it creates the file "1.xml" when i open the file is empty, is there a reason as to why this would be, attached is the html file i'm using, maybe one of you guys can tell me or help me figure this out, I know the html tags on the file may not be very well formatted, this is the only reason i can think the created xml file will be empty.

Any thoughts, or ideas!

here is the file

View attachment 1.zip

 

[Erel]

JTidy fails to parse this file. It outputs many warnings in the unfiltered logs. However there is also 1 error which is not printed for some reason. I tried to manually run JTidy from the command line and the result is the same.

 

[walterf25]

Jtidy

Hi Erel, sorry for not following up on this sooner, I'am now back to trying to update this app, i was wondering can you maybe suggest an easy way to fix this issue, i still can't seem to make jtidy work with the html file i'm using.

 

[Erel]

I'm sorry but it seems to be a problem in JTidy itself. I wasn't able to find the source of this error.

 

[merlin2049er]

That's great. So extracting tags from xml is easier than html?

I need to extract some links to put into my download manager.

 

[Erel]

Yes. Once you convert the html text to proper XML you can use one of the XML parsers to parse it.

 

[Cableguy]

What would be the correct syntax to convert a webpage on the fly, meaning, doing something like

   tid.Parse(WebPage, File.DirRootExternal, "1.xml")

????

 

[Erel]

You need to download the page with HttpUtils2 and then parse it with this library.

 

[Cableguy]

Thanks Erel

 

[mouhaddab]

hi erel:

I want to convert a web page "index.html" to "index.xml" using the example above, but fails parsser and it gives me this error:

"Org.apache.harmony.xml.ExpatParser $ ParseException: At line 16, column 815: not well-formed (invalid token)"

You can find attached the file xlm I had, using JTidy.

tanks

 

[DonManfred]

the paser can not parse javascript

Edit: i guess. I just saw javascript at this line

 

[mouhaddab]

what can i do so, i need to parse any web page loaded in my app, in order to retrive URLs in it.

 

[DonManfred]

i would like to suggest using DOM-Parser. Much easier to find URLs in the document

 

[mouhaddab]

there is a librery on B4A that uses Dom , or I shall do it with javascript ????

 

[DonManfred]

there is a librery on B4A that uses Dom

Have you tried to search the forum before you ask here?

https://www.b4x.com/android/forum/threads/lib-xom.23551/#content