Resolving Conflicting Jar Files in Informatica Platform using Jar Jar Links

Aug 15, 2023

Resolving Conflicting Jar Files in Informatica Platform using Jar Jar Links

If you use different versions of the same Java libraries as Informatica, you may get an exception NoSuchMethodError . This happens when method signatures do not match between different library versions.

This video shows how to use a tool to manipulate and re-package your jar files so they can be loaded into Informatica’s JVM without error.

Example files can be found on the Informatica Communities site.
Jar Jar Links can be found here: https://code.google.com/p/jarjar/

Content

0.7 -> Hi, this Tim Smith and this another video in the "10 Minute Expert" series.

4.65 -> Today I'm going to talk with you about how to resolve conflicts

8.04 -> in jar files when you're doing Java development work inside Informatica.

12.19 -> Now whether you're developing

18.13 -> Java code inside the Java transformation in

21.24 -> PowerCenter, data services or data quality...

24.869 -> The way that gets executed is inside the environment there's a

29.38 -> Java Virtual Machine or JVM.

32.649 -> And inside of it is a classloader. When you request

36.579 -> a class, the class loader is responsible for finding

41.07 -> it and it looks down the classpath. It looks in jar files and in class files.

44.59 -> These files are organized not just

49.92 -> within jar files to group them together but also

53.46 -> in package names in this example you see a job a transformation that's importing

57.89 -> from the package

58.84 -> org.example. When a request is made

62.899 -> to create an object of this type the class loader goes out

66.68 -> and searches the disk for the file that contains that class

71.97 -> and it will load that class. All the definitions

76.369 -> and executable code and allowed it to be executed. This works fine until

81.11 -> you are using different versions.

84.68 -> When you're not able to maintain compatibility. For example,

88.35 -> the method might get deprecated. And another example,

92.549 -> I might have a case where the first example

95.97 -> here we have a findData()

99.22 -> that's being passed a long, now

102.78 -> I a need to pass a string. Because I'm using a new version

106.29 -> of the method and it only expects a string. Well the class loader can go out and

111.93 -> find that as long as you've got the jar file.

114.509 -> And again this works fine.

118.219 -> But what happens if you need to use

122.28 -> the old and the new version of the jar file?

125.43 -> So in that case your first execution might work (or may not depending on

131.459 ->

132.69 -> which classes it finds first. But if we find the

136.93 -> classname and that's loaded, and we try to use the

140.92 -> other version then the class loader will get a conflict

145.3 -> with the two different versions. And will not allow

148.87 -> a duplicate class being loaded. And the request will fail.

152.75 -> because you can't find something to fulfil the method signatures

156.04 -> so the core problem is that

159.09 -> job does not like the same class name being loaded twice

163.41 -> arm so their couple of ways you can

166.819 -> met deal with is the first is if you have access to the source code you can

170.59 -> change the source code

172.349 -> for your library's so in this example will change

176.459 -> or sample to work example B-two's

179.73 -> Pakistan guess change in there won't be a conflict anymore there's another

184.06 -> little utility that I found called George or links in this is very useful

188.14 -> when you're using libraries like apache commons or

191.7 -> lot for J or other

195.03 -> library such as that if you're using those libraries and Informatica uses

200.239 -> those libraries

201.22 -> then it's very possible to hit a conflict if one is using a new were

206.459 -> package than the other newer version library

210.299 -> so what George Arliss does is it allows you to change

215.62 -> the packaging

218.79 -> for a package and for example

223.18 -> I can then have a jar file that contains

226.319 -> workday example and my first job transformation work

230.18 -> then my second job from transformation will

233.68 -> import or did not example underscore be too

236.989 -> so I've renamed it to be too in inside the jar file

240.409 -> in my appropriate folder are

243.59 -> have org example: v2 so even though the original class file

249.799 -> referred to org example: this is able to go

253.269 -> into the jar file just rename the

257.06 -> the different class packages

262.25 -> let me give you a quick example quick demonstration

267.639 -> I've created an example to show how this works I have

271.11 -> a class called shared class that's in the package

274.46 -> or that bogus it has two different methods the first is version

279.31 -> and every turns a strain that is the version so v1

283.18 -> the second is say something and say something accepts

286.57 -> two parameters to strings and all it does is can't make those together

291.35 -> I have another java file called share class and this is my second version so

296.9 -> this is my new version

298.6 -> and when I ask for version I should get the two

301.759 -> but now instead hard-wired two strains I now take an array of strings

307.449 -> and these get concatenate together in return and it also has a space in

312.32 -> between

312.94 -> the different parts so to

316.25 -> classes with the same name and Tom

319.33 -> now above that I have a test harness

322.34 -> the test harness is just test one

326.03 -> contest to you both assume different versions of shared classed s1

330.539 -> has run test and you specify

333.85 -> or that is yet it calls the shared class

337.389 -> concatenate virgin with

342.44 -> a concatenated string first and second so-called say something

345.66 -> with first and second the second

348.93 -> does the same thing but accepts expects a different method signature

353.58 -> it is passing the string array

356.759 -> now I can't compile these and Ryan test line with this shared class and it's

361.47 -> going to XQ

362.36 -> fine I can run test to do with the share classes going to execute fine

366.509 -> and if thou that's all I need to do inside have

369.96 -> you for Mac I was call one of these then I would be fine as long as

373.86 -> nothing else was referring to the the a different version

379.22 -> but I want to force the failure so that's the way I did that

383.699 -> the I have to Java transformations inside the mapping

387.59 -> in a logical object: and these are

391.49 -> Pauline the two different s you'll see here I'm calling test one

396.639 -> in here I'm calling test to and it takes those values whatever those return and

402.36 -> help but

403.759 -> so I can preview

409.46 -> and the here I'm getting version B one

412.88 -> with the result first and second so those go got cagney

416.169 -> concatenated together now let's call this one

419.77 -> and you'll see a very got the error message there

422.789 -> it says no such method air so it loaded

426.849 -> the class in it went ahead and loaded this

431.169 -> class and now

434.46 -> that it's loaded can't see the other class

438.94 -> the location the jar files is found in the services shared jars third-party

444.289 -> that's where you can add your own jar files

447.3 -> and I have compiled those four different files into four different jars

453.389 -> and those are the B-one B-two test harness the want src to you

459.27 -> so we have a conflict with the B-one and B-two you that we need to resolve

465.27 -> the whale resolve that is by combining

468.669 -> the test harness the two with might be to GR

471.879 -> and then changing the contents of that so that the package is different for the

475.789 -> BT joke

477.15 -> you can see what is inside the jar

480.58 -> what the packages are by

483.9 -> ok using jar

487.729 -> and see have got or bogus share class there

491.65 -> and the inside my test harness the two

496.37 -> I have worked as hard as test to

499.43 -> so I'm going to change and want to combine these two together

503.099 -> into one jar file and then I'm going to you

507.53 -> change or bogus to another

510.919 -> path or another package let's go ahead and get ready have

515.76 -> v2 jar

520.719 -> in the test harness the two

528.49 -> and I'll copy the the to you acts dot jar so

533.029 -> the v2 axe

538.55 -> I have renamed or bogus to be

541.92 -> organics or bogus so I've added another layer on top a bit

548.06 -> the test to class was inside the same folder

552.08 -> and that when I win I

555.18 -> ran the the utility on this JAR file yet

558.62 -> change the test to class to look at

561.83 -> this path instead of the previous path for package

565.42 -> so everything's combined together now got one

568.519 -> jar file that has everything that I need I should be able

572.97 -> have done something very wrong should now be able to preview this

578.76 -> and you'll see that my version one is working

583.29 -> and my version two is working be

586.97 -> note that the first and second has a space in between and BTU

590.839 -> got return now how did it work

594.339 -> how does this magic work going to you show you a

597.63 -> batch file that I created and

602.04 -> in this what I'm doing is I compiled the various

605.67 -> files the shared class is compiled

609.149 -> the test harness version 1 /version to you

612.3 -> are compiled and they are then jarred so I jar to b1 b2

618.24 -> night src want SRC to use the class files each going their own separate

622.459 -> files

624 -> then I test to make sure that my test harness is working

627.97 -> I XQ test1 test2 and that does

632.589 -> now they're that that got me too those four jar files that I started out with

637.42 -> when I'm show you

638.14 -> now and going to combine

641.98 -> the jar files for the Virgin to so the test harness version to you and Tess

646.589 -> harsh version 1 the way that I do that

649.3 -> is I have a folder called combine and I

652.47 -> extract all the information and v2 Jr

656.24 -> in the test car sweetie jar and I combine it all back together

660.66 -> into you a temporary

664.089 -> file called pre test harness the 2x

667.8 -> and %ah the final stab

673.209 -> is to you run the Jar Jar to

677.149 -> so under the tools folder I have the Jar Jar

681.16 -> application this execute it I say process

685.32 -> in roles that txt which tells it how to manipulate the

689.2 -> jar file I give it my pre filed

692.519 -> input file and the output file

695.709 -> there's my test times the 2x jar

698.769 -> last step is to copy the file which I didn't wanna do you

702.44 -> indiscriminately so I've got this comment

705.73 -> next thing I want to show you is what the input here

709.12 -> the input rules for charger and lynx is

712.26 -> that is this last file very simple I said

715.839 -> here's the rule I want you look for anything that's in the

719.529 -> org not bogus and I want you to prefix it

722.99 -> with organics that's it

726.339 -> so Jar Jar links reads this text file

731.37 -> executes the all the rules that you can specify there and there's different

735.1 -> types of roles you can create but I only need a simple

737.6 -> your and yet takes the input jar

741.089 -> writes the output jar with modifications

744.94 -> so finally weekend look one more time

749.079 -> and I can say jar he have

752.769 -> you will like it the free

756.37 -> so that's before

763.29 -> and that's after so before everything was under

766.51 -> or bogus now it's under organics were bogus

770.67 -> and that's the way it works some final notes for you

775.079 -> this is this will not work the example using charger links will not work yes

780.779 -> classes are being mainly loaded

783.339 -> the classloader so if that is the case

787.029 -> there's a static string bean used and charger links does not

791.72 -> identify or do anything with that you might be able to use a class file

796.36 -> editor I've seen some out there I didn't need to do that so I haven't tried it

800.97 -> I'm I imagine it would work by that's up to you to you

805.38 -> experiment with that the URL for the judge Orleans

809.06 -> project is on the Google Code site

812.57 -> and if you have any questions about this feel free to post questions from

815.79 -> to the Informatica community by I remember I didn't write this so

820.55 -> I don't support it if you

823.769 -> arm are having problems P please post to the site

827.24 -> I may be able to respond others might respond but

831.769 -> as a community if everyone contributes then

834.93 -> we all benefit from that

838.29 -> and I'll last night lease please let me know if you found this

841.62 -> recording useful the 10 min expert series take some time and I

846.089 -> appreciate any feedback so thanks for your time I hope this was helpful

850.72 -> and until next time

Source: https://www.youtube.com/watch?v=o_9q1Xmld2I