I'm looking to run my Dropwizard 0.8.5 app in debug mode whereby:
The app is running locally, using JPDA; and
In my IDE (Eclipse) I set breakpoints and use a JPDA client to connect to my locally running app (I think this is how it goes)
For the server debug mode:
Typically my DW app runs from the command-line like so:
java -jar build/libs/myapp.jar server src/test/resources/myapp-local.yml
So what are the command-line args to get this running in debug mode (JPDA), or what are the modifications to myapp-local.yml needed to accomplish this?
For Eclipse/JPDA Client
I assume I just set breakpoints and then create a new Debug Configuration inside Eclipse, but not sure what arguments/configs to set this Configuration up with. Any ideas?
Just run the main class (the one that extends Application<T>) in debug mode. You will need to set the program parameters as "server src/test/resources/myapp-local.yml" in your run configurations.
Related
I got stuck in the steps to deploy the play-java application to standalone server. I am using Ubuntu instance running onEc2 machine. After reading the official documentation I followed these steps:
Install typesafe activator to $Home/activator
Copy my project folder to $Home/activator/projects using Jenkins
Run cd $Home/activator/projects/project
Run dist command. It generate the project sh file
Run cd $HOME/activator/projects/sample/target/universal. It shows me three things i.e. sample-1.0.zip , tmp.
Run unzip sample-1.0.zip
Run cd $Home/activator/sample/target/universal/sample-1.0/bin. It shows me two scripts i.e. sample (for mac and linux) and smaple.bat (for windows).
Now, I tried to run this command as documentation says: sample-1.0/bin/sample -Dplay.crypto.secret="abcdefghijk" but it got stuck and shows nothing except a prompt on terminal.
What next steps are required to run the application in daemon mode. So that server will continue to run always?
Another question is why do I need to follow these steps because just after copying the project I can easily run activator run command to sample folder to run the server.
EDIT-1
Now I am getting Error: Could not find or load main class play.core.server.ProdServerStart while running sample -Dplay.crypto.secret="abcdefghijk" command
Play Framework modes
Play like other frameworks can run in different modes because we are usually like to run our program in different situation and these situations need their configuration. Production is one of play modes. In this mode as the name suggested we are ready to deploy our application where user can use.As a result requirements are different.
Some common configuration in Production mode :
We are confining https
Using production data base not testing one
Play doesn't show errors
Play framework run as long term process and if you are log out of your server your application will run
If your app fails Play will clone another application and run that so your app run forever except you turn it off.
and so on (it is based on your Production config file)
Your answer :
If you just want to test your app in remote server and see what happened, it's okay to use activator run this command runes Play app in development mode and application will killed if you exit or log off (error will shows up and so on). But if you want to use your app for Production it is necessary to run all of these steps.
I am trying to debug remote java application in Intellij but unable to get sucess, The steps which I am doing is
Run>Edit Configuration> Defaults> Remote
What is/are I am missing?
First, create a new Remote debugging configuration:
ALT + U + R
Take note of the port which IntelliJ plans to listen in Tomcat. On my setup the port is 8000, which is the default and this should be fine for your setup as well. To change the Tomcat JPDA port, edit catalina.bat (or whatever your startup script is) and find a line which looks like the following:
set JPDA_ADDRESS=8000
Second, make sure that you are building your project with javac -g .... The -g option means that debugging information will be turned on in your Spring WAR.
Finally, when you start Tomcat, use catalina jpda start, which will tell Tomcat to connect the debugger to port 8000. When you want to connect to IntelliJ then use ALT + SHIFT + F9 and select your remote configuration from the menu. Of course, you should add some breakpoints, without which it doesn't make much sense to be in debug mode.
You don't need to edit the defaults. You need to use the [+] button to create a new Remote run configuration and specify its settings.
this functionality used to work and now it seems broken, I a do not know how to diagnose it.
I am developing a java Applet that runs in a browser. I used to set up the runtime parameters in the java console to (Windows platform):
-Djava.compiler=NONE -Xnoagent -Xdebug -Xrunjdwp:transport=dt_socket,address=8000,server=n,suspend=n
This setting appears both in the User and System tabs in the Java console.
Then I would start a debug session in eclipse for my applet project and set it to listen on port 8000. When I launch the browser and the applet is loaded, it would attach to eclipse and I was able to debug and set breakpoints, etc.
Now, it seems that this is no longer happening. When I launch the debug session in Eclipse, I do see port in LISTENING mode and owned by javaw.exe, which is correct. The only problem is that when the browser loads the Java plugin, it does not honor the "Runtime Parameters" and does not connect to the listening debug session in eclipse.
I have the latest Java update installed.
What else should I be looking into?
I just resolved my issue.
I edited:
C:\users\\AppData\LocalLow\Sun\Java\Deployment\deployment.properties
and added the pararameters as follows:
deployment.javaws.jre.0.args=-Djava.compiler\=NONE -Xnoagent -Xdebug -Xrunjdwp\:transport\=dt_socket,address\=8000,server\=n,suspend\=n
When i added the runtime parameters through the UI, they went to
"deployment.javaws.jre.1.args" so I duplicated them into "deployment.javaws.jre.0.args"
Can you attach to a running application using Eclipse, similar to how you attach using Visual Studio?
Yes.
If you start your server with the debug port open, by adding this into your java command:
-Xdebug -Xrunjdwp:transport=dt_socket,address=127.0.0.1:8888,server=y,suspend=n
And you have the source code in your project (technically this isn't required, but it's kind of useless unless you do), you can connect to the running server by setting up a "debug configuration"
with host = the machine the server is running on and port = 8888 (for example - see options above)
You can then set break points and the debug session will halt the server there and you can inspect variables/fields, and even set their values.
Update
The more modern command-line options for the JVM to do this are
-agentlib:jdwp=transport=dt_socket,address=127.0.0.1:8888,server=y,suspend=n
The Debug Configurations panel has a menu item Remote Java Application:
How about just do this:
"Open the DDMS perspective, select the device and attach to your app's process (you will see the package name listed)"
.. thanks to this post: https://stackoverflow.com/a/10074263/2162226
I would like to debug my separately running JSP/Struts/Tomcat/Hibernate application stack using the Eclipse IDE debugger. How do I setup the java JVM and eclipse so that I can set breakpoints, monitor variable values, and see the code that is currently executing?
I just Googled it. :)
http://bugs.sakaiproject.org/confluence/display/BOOT/Setting+Up+Tomcat+For+Remote+Debugging
Many more on google.
Effectively, set your JPDA settings:
set JPDA_ADDRESS=8000
set JPDA_TRANSPORT=dt_socket
bin/catalina.bat jpda start
Then, in Eclipse, Run->Debug Configurations...->Remote Applications.
Follow these steps:
Add the following arguments to the java command that is used to launch Tomcat (on Windows, I think this is in TOMCAT\bin\catalina.bat)
-Xdebug -Xrunjdwp:transport=dt_socket,address=8787,server=y,suspend=n
In Eclipse, create a 'Remote Java Application' debug configuration and set the port to 8787 and the host to the name (or IP address) of the machine where Tomcat is running. If Tomcat is running on the same machine as Eclipse, use 'localhost'.
In the 'source' tab of the debug configuration, add any projects that you want to debug into
Start Tomcat
Launch the debug configuration you created in step 2
Eclipse should now stop at any breakpoints that you've set in the projects you added in step 3.
Notes:
You can change the port to any other available port if for some reason you can't use 8787
If you want Tomcat to wait for the remote debugger to start, use 'suspend=n' in the command above to 'suspend=y'
You could do what they suggest, or use this Eclipse plugin, which makes it easier to configure Tomcat to begin with: Eclipse Tomcat Plugin
When launching tomcat via this plugin, it starts in debug mode by default, you must explicitly disable debugging mode if you want it to not allow Eclipse to connect a remote debugger.
For Tomcat 5.5 on Windows:
Edit bin/startup.bat
Find the line that reads:
call "%EXECUTABLE%" start %CMD_LINE_ARGS%
Replace it with these lines:
set JPDA_ADDRESS=8000
set JPDA_TRANSPORT=dt_socket
call "%EXECUTABLE%" jpda start %CMD_LINE_ARGS%