Friday, October 27, 2017

Re: Bizzare "[ERROR] Invalid module name" Bug Upon Launching Dev Server

That happens to me when removed the dependencies in the plugin. I was using maven to organize the project, then by error, I removed the dependencies block inside the gwt-maven-plugin in the build part.

El martes, 18 de octubre de 2011, 22:47:47 (UTC+2), Simon escribió:
This is without a doubt one of the most bizzare/inexplicable issues
I've experienced since I've begun programming.

I'm developing a multi-module GWT project that formerly had one of its
modules contained entirely within a JAR file.  I decided that this
particular module (the "com.allen_sauer.gwt.dnd.gwt-dnd" module, to be
specific) needed more work, so I extracted it from its JAR, removed
said JAR from the project's classpath/ build path, and proceeded to
insert all the relevant Java packages and the .gwt,xml file into the
"src" directory of my Eclipse project (where the rest of my modules
currently live), ensuring to retain exactly the same directory
hierarchy the module had while it was contained in the JAR.

When I tried to run the project as a local Java Development server
from Eclipse, it immediately crashed with an error that read:

Loading modules
      [ERROR] Invalid module name: 'com.allen_sauer.gwt.dnd.gwt-dnd'
[ERROR] shell failed in doStartup method

Although I proceeded to attempt to troubleshoot this problem by double-
checking my work and trying various ways to achieve my goal of
bringing the gwt-dnd's source into my project without creating this
error, the error remains.

Here's where the plot thickens:  eventually I just used my SVN
server's revert command to restore my project back to exactly the way
it was working before attempting to bring the other JAR's module into
the main body of my project.  Surprisingly, when I tried to run it,
the " Invalid module name" error remained just as if I hadn't reverted
the project at all!  Interestingly enough, when I pulled a fresh copy
of that same project down from SVN, the error was gone and my project
ran just as well as it always had.

Determined to get to the bottom of this issue, I closed Eclipse and
used BeyondCompare3 to do a binary folder comparison between the
"broken" reversion and the working clean copy.  Although there were
subtle, minor differences between the two (mainly in the log files and
generated timestamps), I copied all these minor changes from the clean
copy back into the broken one.  Now, with both of these projects
BINARILY IDENTICAL, I re-opened Eclipse and lo-and-behold, the broken
project still gives me that same Invalid Module Name error and the
clean copy still works!

Because all the relevant project settings and properties files are
contained within the project directory in Eclipse,I'm at a total loss
on this one, does anyone have any suggestions or guidance?

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