问题
I've worked with GWT and eclipse for a while now and I wanted to play a bit with maven and the GWT plugin (gwt-maven-plugin, enter link description here). I tried to use it out of eclipse (Luna 4.4), but obviously I didn't do it correctly, as it was extremely brittle to the point that it broke on a regular basis as the IDE overwrote it's settings when I changed something small in the pom.xml. So I decided to take a step back and eliminate the black magic that eclipse is and start a new project from scratch from the command line.
However, I cannot seem to be getting the hang of running the actual application, because when I execute the code server, navigate to the page, I see the following message:
Can't find any GWT Modules on this page.
Obviously, the code server is running, however the module files seem to not have been hosted. AFAIK I see after several hours of educating myself (and finding http://blog.ltgt.net/how-does-gwts-super-dev-mode-work/), there should be a second process actually hosting the code in parallel to the code server. What is the appropriate way of doing this with maven? Should I open a second terminal and run a jetty or something else in parallel to the code server? If so, could someone please give me a hint how I can do it most efficiently?
Thanks in advance!
Here is how I created the project:
mvn archetype:generate \
-DarchetypeGroupId=org.codehaus.mojo \
-DarchetypeArtifactId=gwt-maven-plugin \
-DarchetypeVersion=2.7.0
[INFO] Scanning for projects...
[INFO]
[INFO] ------------------------------------------------------------------------
[INFO] Building Maven Stub Project (No POM) 1
[INFO] ------------------------------------------------------------------------
[INFO]
[INFO] >>> maven-archetype-plugin:2.2:generate (default-cli) > generate-sources @ standalone-pom >>>
[INFO]
[INFO] <<< maven-archetype-plugin:2.2:generate (default-cli) < generate-sources @ standalone-pom <<<
[INFO]
[INFO] --- maven-archetype-plugin:2.2:generate (default-cli) @ standalone-pom ---
[INFO] Generating project in Interactive mode
[INFO] Archetype repository missing. Using the one from [org.codehaus.mojo:gwt-maven-plugin:2.7.0] found in catalog remote
Define value for property 'groupId': : com.mytest
Define value for property 'artifactId': : gwtmvntest
Define value for property 'version': 1.0-SNAPSHOT: :
Define value for property 'package': com.mytest: : com.mytest.gwtmvntest
Define value for property 'module': : GwtMvnTest
Confirm properties configuration:
groupId: com.mytest
artifactId: gwtmvntest
version: 1.0-SNAPSHOT
package: com.mytest.gwtmvntest
module: GwtMvnTest
Y: :
[INFO] ----------------------------------------------------------------------------
[INFO] Using following parameters for creating project from Archetype: gwt-maven-plugin:2.7.0
[INFO] ----------------------------------------------------------------------------
[INFO] Parameter: groupId, Value: com.mytest
[INFO] Parameter: artifactId, Value: gwtmvntest
[INFO] Parameter: version, Value: 1.0-SNAPSHOT
[INFO] Parameter: package, Value: com.mytest.gwtmvntest
[INFO] Parameter: packageInPathFormat, Value: com/mytest/gwtmvntest
[INFO] Parameter: package, Value: com.mytest.gwtmvntest
[INFO] Parameter: version, Value: 1.0-SNAPSHOT
[INFO] Parameter: module, Value: GwtMvnTest
[INFO] Parameter: groupId, Value: com.mytest
[INFO] Parameter: artifactId, Value: gwtmvntest
[INFO] project created from Archetype in dir: /private/tmp/mvn/gwtmvntest
[INFO] ------------------------------------------------------------------------
[INFO] BUILD SUCCESS
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 08:12 min
[INFO] Finished at: 2015-01-14T12:59:17+01:00
[INFO] Final Memory: 15M/310M
[INFO] ------------------------------------------------------------------------
Here is how I compiled the project:
mvn compile gwt:compile
[INFO] Scanning for projects...
[INFO]
[INFO] ------------------------------------------------------------------------
[INFO] Building GWT Maven Archetype 1.0-SNAPSHOT
[INFO] ------------------------------------------------------------------------
[INFO]
[INFO] --- gwt-maven-plugin:2.7.0:generateAsync (default) @ gwtmvntest ---
[INFO]
[INFO] --- maven-resources-plugin:2.6:resources (default-resources) @ gwtmvntest ---
[INFO] Using 'UTF-8' encoding to copy filtered resources.
[INFO] Copying 2 resources
[INFO]
[INFO] --- maven-compiler-plugin:3.1:compile (default-compile) @ gwtmvntest ---
[INFO] Changes detected - recompiling the module!
[INFO] Compiling 6 source files to /private/tmp/mvn/gwtmvntest/target/gwtmvntest-1.0-SNAPSHOT/WEB-INF/classes
[INFO]
[INFO] --- gwt-maven-plugin:2.7.0:compile (default-cli) @ gwtmvntest ---
[INFO] Compiling module com.mytest.gwtmvntest.GwtMvnTest
[INFO] Compiling 5 permutations
[INFO] Compiling permutation 0...
[INFO] Process output
[INFO] Compiling
[INFO] Compiling permutation 4...
[INFO] Process output
[INFO] Compiling
[INFO] Compiling permutation 3...
[INFO] Process output
[INFO] Compiling
[INFO] Compiling permutation 2...
[INFO] Process output
[INFO] Compiling
[INFO] Compiling permutation 1...
[INFO] Compile of permutations succeeded
[INFO] Compilation succeeded -- 13.866s
[INFO] Linking into /private/tmp/mvn/gwtmvntest/target/gwtmvntest-1.0-SNAPSHOT/GwtMvnTest
[INFO] Link succeeded
[INFO] Linking succeeded -- 0.171s
[INFO] ------------------------------------------------------------------------
[INFO] BUILD SUCCESS
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 18.228 s
[INFO] Finished at: 2015-01-14T13:07:07+01:00
[INFO] Final Memory: 22M/310M
[INFO] ------------------------------------------------------------------------
Here is how I ran the project:
mvn gwt:run-codeserver
[INFO] Scanning for projects...
[INFO]
[INFO] ------------------------------------------------------------------------
[INFO] Building GWT Maven Archetype 1.0-SNAPSHOT
[INFO] ------------------------------------------------------------------------
[INFO]
[INFO] >>> gwt-maven-plugin:2.7.0:run-codeserver (default-cli) > process-classes @ gwtmvntest >>>
[INFO]
[INFO] --- gwt-maven-plugin:2.7.0:generateAsync (default) @ gwtmvntest ---
[INFO]
[INFO] --- maven-resources-plugin:2.6:resources (default-resources) @ gwtmvntest ---
[INFO] Using 'UTF-8' encoding to copy filtered resources.
[INFO] Copying 2 resources
[INFO]
[INFO] --- maven-compiler-plugin:3.1:compile (default-compile) @ gwtmvntest ---
[INFO] Nothing to compile - all classes are up to date
[INFO]
[INFO] <<< gwt-maven-plugin:2.7.0:run-codeserver (default-cli) < process-classes @ gwtmvntest <<<
[INFO]
[INFO] --- gwt-maven-plugin:2.7.0:run-codeserver (default-cli) @ gwtmvntest ---
[INFO] Turning off precompile in incremental mode.
[INFO] Super Dev Mode starting up
[INFO] workDir: /var/folders/nk/58gyq85x7l3_mzb5rc0gw42w0000gn/T/gwt-codeserver-5859907708379954718.tmp
[INFO] Loading Java files in com.mytest.gwtmvntest.GwtMvnTest.
[INFO] Module setup completed in 11742 ms
[ERROR] 2015-01-14 13:14:35.800:INFO:oejs.Server:jetty-8.y.z-SNAPSHOT
[ERROR] 2015-01-14 13:14:35.833:INFO:oejs.AbstractConnector:Started SelectChannelConnector@127.0.0.1:9876
[INFO]
[INFO] The code server is ready at http://localhost:9876/
回答1:
With GWT 2.7+ all you need is to launch mvn gwt:run and it'll use SuperDevMode under the cover, with "recompile on load" (instead of using bookmarklets).
Note that gwt:run won't copy your src/main/webapp or your dependencies, so you'll likely have to run mvn war:exploded (or mvn package) as a prerequisite (and every time you change a file in src/main/webapp or you need to refresh your dependencies)
That being said, unless your project is really simple, you should start using distinct Maven modules early for client and server code; this is because Maven insists that you cannot manage a "GWT client-side classpath" and a "server-side classpath" in the same POM.
I published archetypes to help setting everything up: https://github.com/tbroyer/gwt-maven-archetypes (I unfortunately haven't had the time yet to update them to GWT 2.7)
Either that or use Gradle…
来源：https://stackoverflow.com/questions/27942953/gwt-code-server-not-finding-a-module-in-a-newly-generated-project-using-a-maven