Development Mode in Eclipse stopped working - no errors, nothing on console

[tanteanni]

On integrating a library on server side of my gwt app (maven, gwt 2.4) the development/hosted mode stopped working. The app works fine if deployed and all unit tests and integration tests pass as before. 

If i start development mode (run/debug as web application) the develpoment mode view pops up but nothing else happens. normally the console should show some output but console keeps empty. So i don't even have a hint whats going wrong.

Can you give some advice where to look / what to do to get at least a hint what's wrong?

(if i check out the revision before the development mode works! - so some code changes should be the cause?!)

Background about library i added (don't know if my problem relates to this):I had some problem on integrating the library. the library uses eclipse birt charting engine. This engine has a dependency to apachy derby db, this conflicted with another library. i solved this by excluding the derby dependency via maven. the second problem was a "command line too long" error on unit test - this was solved by updating the maven-surefire-plugin.

[tanteanni]

i did some researches: the hosted mode stops working if i only add the dependency - without using it. as mentioned above i checked out the revision before adding and using this lib. based on that revision i only added the dependency to pom and the hosted mode stops working. on deleting the dependency it is working again.

[Thomas Broyer]

On Wednesday, September 12, 2012 2:07:06 PM UTC+2, tanteanni wrote:

i did some researches: the hosted mode stops working if i only add the dependency - without using it. as mentioned above i checked out the revision before adding and using this lib. based on that revision i only added the dependency to pom and the hosted mode stops working. on deleting the dependency it is working again.

Incompatibility with some (embedded) dependency of GWT? (ECJ/JDT maybe, or some Apache Commons)

Short-term solution: exclude BiRT from the DevMode classpath (try using "mvn gwt:run" or "mvn gwt:debug" to launch the DevMode, and use runClasspathExcludes to exclude BiRT: http://mojo.codehaus.org/gwt-maven-plugin/debug-mojo.html#runClasspathExcludes)

Long-term solution: use separate modules for client-side and server-side (and shared) code, so that your client-side module only has dependencies on client-side libraries, that are much less likely to collide with the DevMode (and Compiler, BTW).

[tanteanni]

thx thomas,

i should mention that gwt:run works fine. is there a way to see conflicting dependencies? to get rid of the conflicting derby dependency i used "mvn dependency:tree -Dverbose". This shows only one conflict for gwt stuff:

[INFO] |  +- (javax.validation:validation-api:jar:1.0.0.GA:provided - omitted for duplicate)

[INFO] |  \- (javax.validation:validation-api:jar:sources:1.0.0.GA:provided - omitted for duplicate)

(Maven should handle all conflicts)

i just tried to added 

<configuration>

<runClasspathExcludes>

<excludes>org.eclipse.birt.runtime-4.2.0.jar</excludes>

</runClasspathExcludes>

<configuration>

to gwt-maven-plugin's configuration but it changes nothing. - not sure if i 've done it right?

Is there an example for the long term solution you suggested? I guess with modules you mean maven modules? - Such an big change in projects configuration i only want to do if i am sure that this solves my current problem and there's no easier way.

[Thomas Broyer]

On Wednesday, September 12, 2012 3:51:49 PM UTC+2, tanteanni wrote:

thx thomas,

i should mention that gwt:run works fine. is there a way to see conflicting dependencies? to get rid of the conflicting derby dependency i used "mvn dependency:tree -Dverbose". This shows only one conflict for gwt stuff:

[INFO] |  +- (javax.validation:validation-api:jar:1.0.0.GA:provided - omitted for duplicate)

[INFO] |  \- (javax.validation:validation-api:jar:sources:1.0.0.GA:provided - omitted for duplicate)

(Maven should handle all conflicts)

See http://code.google.com/p/google-web-toolkit/issues/detail?id=4484 (among others)

i just tried to added 

<configuration>

<runClasspathExcludes>

<excludes>org.eclipse.birt.runtime-4.2.0.jar</excludes>

</runClasspathExcludes>

<configuration>

to gwt-maven-plugin's configuration but it changes nothing. - not sure if i 've done it right?

Forgot to say that it only works with gwt-maven-plugin 2.5.0-rc1; see http://jira.codehaus.org/browse/MGWT-286

Also, I suppose the offending JAR is not org.eclipse.birt.runtime-4.2.0.jar directly but one of its dependencies.

Is there an example for the long term solution you suggested?

https://github.com/tbroyer/gwt-maven-archetypes for example.

 

I guess with modules you mean maven modules?

Absolutely.

[tanteanni]

How does the issue you mentioned explains why all is running fine (gwt:run, deployed) but it fails in eclipse hosted mode? Or how to get know the name of the conflicting jar to be excluded via "runClasspathExcludes"? 

is gwt-maven-plugin 2.5-rc1 working with gwt 2.4?

because my "only" problem is eclipse' hosted mode i want to be sure that refactoring to multi modules is the only but sure way to solve this problem.

[Thomas Broyer]

On Wednesday, September 12, 2012 4:46:57 PM UTC+2, tanteanni wrote:

How does the issue you mentioned explains why all is running fine (gwt:run, deployed) but it fails in eclipse hosted mode? Or how to get know the name of the conflicting jar to be excluded via "runClasspathExcludes"? 

is gwt-maven-plugin 2.5-rc1 working with gwt 2.4?

because my "only" problem is eclipse' hosted mode i want to be sure that refactoring to multi modules is the only but sure way to solve this problem.

Ah sorry, didn't see that gwt:run works OK. runClasspathExcludes won't change anything then, as it only applies to gwt:run.

If your only problem is with Eclipse, then I don't see any other thing to do than compare the classpaths (run "mvn -X gwt:run", it should then display the classpath used for launching the DevMode; and compare to what's being used in the Eclipse launcher; there should be a mean –some process explorer, or maybe JConsole– to see what command line has been used by Eclipse to launch the DevMode and see what it put in the classpath)

Also maybe try connecting to the DevMode even if nothing appears in Eclipse.

As a last resort, create a "Java Application" run configuration in Eclipse, choosing com.google.gwt.dev.DevMode as the main class; that way you'll have complete control over what happens, and you can use "Debug as..." in Eclipse (much better than gwt:debug)

[tanteanni]

thx thomas,

if you hav no answer who else could :-( ?

I've got some new info: On of us could run dev mode from eclipse (indigo), on at least two machines - helios, juno it is not working. The one that has the working config is thze only one whoe uses java 7 as execution environment. I also tried to connect to dev-mode process via jconsole but this fails ("connecting to ..." runs forever) but on process selection i could see the commandline used: it has no "-classpath" it start with "com.google.gwt.DevMode -war ...".

Since i neither could connect to dev-mode process nor eclipse is showing any error i think it is some odd java problem?! do you have any ideas about that?

over night i thought about your multi module idea - i am beginning to like it. are there any disadvantages about that - especially in interoperability with eclipse (i want my eclipse dev mode back). In such a multi-module project i guess the dev mode is launched from client module?

[tanteanni]

It is running with java 7! 

 (don't ask why)