Deployment Descriptors Referencing External DTDs

[Kiran Kumar]

Hello Experts,

We all know that web.xml and application.xml have


code:
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<!DOCTYPE web-app PUBLIC "-//Sun Microsystems, Inc.//DTD Web Application 2.3//EN" "http://java.sun.com/dtd/web-app_2_3.dtd">

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and

code:
--------------------------------------------------------------------------------

<!DOCTYPE application PUBLIC "-//Sun Microsystems, Inc.//DTD J2EE Application 1.3//EN" "http://java.sun.com/dtd/application_1_3.dtd">

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.. respectively.

They reference the DTDs on java.sun.com. So, my application depends on the DTD's on an external site. How do I maintain fail over as I don't want my applications to fail incase the DTDs are temporarily down at java.sun.com.

I know that I can have the DTDs copied and put as inline DTDs in my deployment descriptors, but I was thinking about hosting these DTDs on my company's servers and making my deployment descriptors point to them. But, my deployment fails for some reason. Is there more configuration to do in this regard?

In my investigation I read about Catalog files etc. Is that the way to go? If yes, how is it done?

Any pointers appreciated!
Thanks in advance,
Kiran

[Chengwei Lee]

Have you tried to change the <DOCTYPE> to something like these:

    
  <!DOCTYPE web-app PUBLIC "-//Sun Microsystems, Inc.//DTD Web Application 2.3//EN" "http://www.mycompany.com/dtd/web-app_2_3.dtd">
 
  <!DOCTYPE application PUBLIC "-//Sun Microsystems, Inc.//DTD J2EE Application 1.3//EN" "http://www.mycompany.com/dtd/application_1_3.dtd">

Of course you must have the two DTDs physically available at that URL. But, keeping them on your own website doesn't means that your server won't have downtime.

Ideally you should put the DTDs to your EAR/WAR, that way, you won't have to worry if someone accidentally removed the files from the server. If you've fail-over, even if 1 server is down, the other will still work, since the DTDs are inside your WAR/EAR.

[Kiran Kumar]

Chengwei,

Thanks for the reply!

I guess having DTDs in the war/ear is the way to go. In that case, how does my <!DOCTYPE looks like?

I tried

   <!DOCTYPE application SYSTEM "application_1_3.dtd"> 

and putting application_1_3.dtd in my META-INF directory. But it fails.

Thanks,
Kiran

[Pratheep Nair]

Did you try putting it in the WEB-INF\lib folder?

[Kiran Kumar]

Pratheep,

I am talking about application.xml which is a DD for Enterprise Application and not web application project. I tried putting it in META-INF together with application.xml and used "application_1_3.dtd" as the system identifier. I also tried using "file://application_1_3.dtd" but nothing works.

Thanks,
Kiran

[Michael Ernest]

This sounds like an XML topic to me. Moving it accordingly.