Is there a best approach to debug maven GWT application at Eclipse Che?
Whenever I run gwt:run-codeserver it maps to a random external port on docker in order to serve multiple users, and the client is expecting to use the port, specified at pom configuration.
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I want to know the difference in running an application in eclipse by both ways below:
1)Run the application as maven build with 'tomcat' dependency in the pom.xml
2)download tomcat from apache site and add the server, run the tomcat and then run the application as server.
Lets say, my project name is 'messenger'. When I did using first step, i can access with below link"
http://localhost:8080/
but when i did as second step, i can access using below link:
http://localhost:8080/messenger/
can someone, please explain why the difference? arent both the same?
I am currently working on a project which has a GWT frontend and a seperate Java module with servlets and a REST interface on the backend. The project when deployed runs on a single JBoss server.
I am running into difficulties though as when I run the GWT app in hosted mode (in eclipse) the jetty server does not have a deployed Java module to interact with.
My idea was to setup a JBoss server which eclipse could deploy into for development purposes, the problem with this is that the installer for the product sets up a JBoss server with a GWT app already embedded in it, so redeploying into this JBoss instance might cause problems?
My other idea would be to create a second JBoss server to host the GWT app, with some sort of url redirect for the rest calls which would redirect to the first JBoss instance. Is this possible?
EDIT: Can I do this with the built in jetty server in eclipse and not have to worry about using a seperate JBoss server. In other words can I somehow get the jetty server in eclipse to redirect particular requests to a different URL?
I'm setting up a project to use MySQL as the datasource and I'm running into a couple problems.
It appears the MySQL drivers for the Java side are incompatible with the built in GWT Jetty instance. Really?
I can configure a TomCat instance and get MySQL Driver working, but I can't debug inline (Client & server together) like I normally would be able to do using the Jetty instance in dev mode, according to Google Docs.
I spent quite a while deciding between a PHP or Java backend, and one of the main advantages besides the GWT RPC mechanism was the fact that GWT provides a nice Development environment if you use Java.
Has anyone encountered the need to use a data source other than appEngine? How did you setup dev environment?
I do believe the MySQL JDBC driver is "compatible" with the embedded Jetty; but maybe you were in an AppEngine project, in which case the embedded Jetty server forbids the use of classes that are not compatible with AppEngine (so you have at dev time a behavior as similar as possible with the production environment on Google's servers).
To debug your server code running in Tomcat, you either need to launch it (the server code) using Eclipse WTP (or equivalent if you don't use Eclipse), or launch your Tomcat instance with the appropriate debug arguments e.g. -agentlib:jdwp=transport=dt_socket,address=8788,server=y,suspend=y, and then debug it as a "Remote Java Application" (in Eclipse, I don't now how they name it in other IDEs).
You can then launch your DevMode in -noserver mode (and in debug) to debug your server and client at the same time (yes, you'll actually have 2 debug sessions).
Note that the doc you refer to (whose latest version can be found here) doesn't deal with debugging the server-side code, as it's highly dependent on the server you use, how and where it's deployed, etc. GWT code on the server side is just a standard servlet, so there's nothing specific to GWT re. how to debug the server-side code.
FYI, we do use a standalone Jetty instance (not the embedded Jetty server) for more than a year using the above setup.
You can use GWT and Tomcat and still be able to debug both client and server side. Look at the jetty startup parameters in Eclipse.
I have been in a similar position few years ago and decided to use Jetty for development and tomcat for testing.
I have a Maven project which is a web project and is packaged as a war.
I use tomcat-maven-plugin v1.2-SNAPSHOT to do a tomcat:deploy when i want to deploy.
But my question is how do i debug it / set breakpoints like i can do for normal web projects in eclipse (where a Debugging perceptive is shown and the server is paused.)
(i am a noob in this field)
[EDIT] I am not asking how to deploy to TOMCAT. i am rather asking how to setup the debug mode .FYI i am not able to right click on my project and select run> run on server, even though i have generated WTP specific files through maven.
mvn tomcat:deploy deploys an app to an external Tomcat server. If you want to debug that, you'll need to run that Tomcat server with debugging enabled and set up a remote debugging profile in Eclipse.
Edit: There's a succinct guide to doing this on the Tomcat wiki. The simplest approach is to start Tomcat with catalina jpda start. That will start Tomcat in debug mode listening on port 8000 for debugger connections. Then in Eclipse, you create a "remote" launcher configuration and tell it to connect to localhost:8000.
It doesn't matter whether you deploy it with maven or with Eclipse WTP as long as you started the server to which you deploy from eclipse and eclipse knows where the sources of the code you deployed are placed.
Keep attention if you have set the CATALINA_HOME environment variable, this will used to deploy to with mvn tomcat:deploy. But you can also define this in the configuration of the pom.xml.
<configuration>
<url>http://www.mydomain.com:1234/mymanager</url>
</configuration>
I'm not sure that it is feasible through the Maven plugin.
But you can generate eclipse specific files: mvn eclipse:eclipse -Dwtp.version=2.0 (The WTP version depends on the WTP version of your Eclipse).
Then, you can update your project and deploying it into a Tomcat like you can do for normal web projects.
This solution worked in my case, you can try this
Add module to Server
Go to the Servers view.
Double click on the Tomcat server.
You will get the server editor view.
Click on Modules tab in view (at bottom)
Click add External Web Module enter the path to your built files (e.g., C:\svn\projectName\trunk\test\project\target\webapp) and give a path.
Save.
Debug Server
Right-click on Tomcat in Servers view.
Choose Debug.
Debugging Startup
If you are debugging the startup of your application you might need to increase the startup timeout in the server view.
Thanks.
I'm developing a web UI using GWT. While working only with the widgets I could debug from Eclipse using the Firefox extension, but now that I'm integrating the UI with other OSGi bundles I cannot use this solution.
For deploying the GWT application I create the .war and convert it to an OSGi bundle using BND. Then I launch the OSGi container with all the bundles using Pax Runner and Pax Web and the application works correctly, but when something fails in the generated javascript code I don't have any decent output error or debugging facility.
Is there any way to launch the GWT application in "debug mode" from OSGi?
Any other idea that could help in this scenario?
Update: Could it be possible to instantiate com.google.gwt.dev.DevMode or its part with the browser connector from the Activator?
I've finally managed to launch development mode using OSGi, GWT and optionally eclipse. The solution was on the -noserver flag of the GWT dev mode, it's not aware of the changes in code while the application is running, but it can be used for debugging the compiled code and to receive the exception traces.
I also managed to run the development shell without eclipse, but if you are not interested on this solution you can directly jump to the eclipse integration section.
Without Eclipse (only exceptions, no debug)
You need to know the following information:
Where do you have your source ($SRC)
Where do you have your GWT libraries ($GWT_PATH), specially gwt-user.jar and gwt-dev.jar.
(Optionally) the port from wich your HTTP OSGi server serves the application ($PORT).
The startUp url of your application ($URL)
The package containing the .gwt.xml file for your application ($PACKAGE).
Then you need to run:
java -cp $SRC:$GWT_PATH/gwt-user.jar:$GWT_PATH/gwt-dev.jar \
com.google.gwt.dev.DevMode -noserver -port $PORT \
-startupUrl $URL $PACKAGE
E.g.:
java -cp src/:lib/gwt-2.0.3/gwt-user.jar:lib/gwt-2.0.3/gwt-dev.jar \
com.google.gwt.dev.DevMode -noserver -port 8080 \
-startupUrl httplocalgui.html es.warp.samples.httplocalgui
And finally you only need to deploy your application as usual, in my example I do it with pax-runner and pax-web, using the default port 8080.
With Eclipse
Open the debug configuration for your project
Go to Server tab and uncheck "Run built-in server"
Go to Attributes tab and add "-port 8080" (if 8080 is the port used by your web container). I think that this argument without the built-in server is only used to create the url that the development mode generates to invoke the browser (or that elipse uses to generate an url you can copy and paste in your browser's address bar).
Deploy your application.
Access it from a browser with the GWT extension installed (and don't forget to add ?gwt.codesvr=127.0.0.1:9997)
I had the same problem lately and unfortunately I haven't found any good solution.
Eventually I created mock implementations of all GWT services I am using in my client side code. When I need to debug client side code I am just switching to these services instead of real services using OSGi underneath. Then in Eclipse I can run GWT application in debug mode. This is far from perfect and requires some work with mocks but it works for me (at least now).