Signing a jar slows app when first time accessing data from servlet

wht do u mean by signing a jar ?

Hi karanw,

We have purchased a certificate for signing jar-files. So I'll sign the jar-file with that sertificate to avoid security warnings; which are otherwise shown to the user when he/she starts the app. Usually we use WebStart to start the app, but now for showcase and testing, the jar-file is started from the command prompt.

/ mika

> Does this delay come from cert trying to check that it is valid?

would say so

> Is there any workaround on this?

should just be a once off if user says to trust cert always

Hi Objects,

There is also difference when jar is started from command propmt vs. double clicking. If I start the program with java -jar prog.jar, the delay is not so long (maybe 2 - 3 sec which is good enough).

After a little testing I am not sure that the validating is the issue which is delaying the first acces to servlet (Maybe signing the jar makes some other changes to the jar). The cpu load is in 100 % when delay is on.

What am I missing here?

Cheers,
Mika

http://www.pankaj-k.net/archives/2004/06/who_or_what_is.html

Hi Objects,

Thanks for the link. I would think that this might be the same issue.
I use the javax.crypto.* classes to encrypt datatransfer over the internet. The jar size is about 5MB. I am using JRE 1.5.0_08.

Here are some timings:

no jar: 359 ms

Running from command prompt (java -jar app.jar):
=================================
unsigned jar: 953 ms
signed jar: 1437 ms

Running with double clicking the jar:
=======================
unsigned jar: 986 ms
signed jar: 23144 ms

My desktop is P4 3.00GHz, 1GB RAM.

Regards,
Mika

> signed jar: 23144 ms

thats the strange one, check what the .jar association is ie. what it runs

try this:

javaw -jar app.jar

Hi Objects,

It is opened by: Java(TM) 2 Platform Standard Edition binary. Have no idea where this links to..

The time with javaw -jar app.jar is: 1531 ms.

I don't see how that can take so much longer, you can check the file mappings in
Tools>Folder Options>File Types

The mapping is: Java(TM) 2 Platform Standard Edition binary, but have no idea where that is mapped to..

Standard Edition binary? java.exe? javaw.exe? which parameters does it use?

I'll try to debug the app deeper to find where the delay actually is..

you can check further and find the exact copmmand it executes.

Hi,

Sorry, had no time to test this earlier, but here it is:
The rows that consume lots time are:

     private Cipher cipherAES = null;
     private SecretKeySpec skeySpec = null;

     skeySpec = new SecretKeySpec(key, "AES");
     cipherAES = Cipher.getInstance("AES");
     cipherAES.init(Cipher.DECRYPT_MODE, skeySpec);
     return cipherAES.doFinal(toDec);

Expecially the row: 'cipherAES.init(Cipher.DECRYPT_MODE, skeySpec);' takes the 99.99% of the time (and only if the jar package is signed). Any suggestions?

/ mika

i meant the windows command it executes.
it appears javaw is taking considerably longer than java

Hi objects,

I think that I found what causes the problem. I previously told that I was using jre 1.5.0_08, but I think that the link from windows to .jar file was to version 1.5.0_06 even I had ver _08 installed.

When running the jar with _06, the delay is very long (appox. 25 sec), but when using jre ver _08, the delay is quite short (maybe that 1,5 sec). _07 is as fast as _08.

I'll try to find what Sun did with the _07 jre..

Cheers,
Mika

Hi,

Found this:

6354728       java       classes_security       Verification of signed JAR files is very slow (performance reduction)

Patched to _07.

/ mika

ah, thats explains the time discrepancy. was getting confused :)