If you are using Eclipse and your development server is running in the debugger, when you save your changes to this file, Eclipse compiles the new code automatically, then attempts to insert the new code into the already-running server. Changes to classes, JSPs, static files and appengine-web.xml are reflected immediately in the running server without needing to restart
plz any one can explain this ??????????
For classes like JSP-files:
Its debugging using JPDA.
The IDE attach via socket to the JVM your running app and hot-redeploy the not-permanent-code (aka PermGen).
There are different techiques and frameworks for that:
http://en.wikipedia.org/wiki/Java_Platform_Debugger_Architecture
It doesn't happen automatically. Check Project --> Build Automatically option. It should have been checked.
If you un-check it; then project will not be build/deployed automatically.
Related
I have recently started developing an Eclipse plugin (which is basic stuff for now) and I am struggling with "default" way to run Eclipse plugin ("Run as Eclipse application").
The Eclipse is starting another instance with my plugin already installed in it (this is default behaviour).
The problem is that when I want to re-run my plugin project and I press "run" button again (or Ctrl + F11) (and the another Eclipse instance still running) I get following message:
"Could not launch the application because the associated workspace is currently in use by another Eclipse application".
The error makes sense, and when I close "testing" Eclipse instance I am able to run my plugin again.
The question is - "is it normal routine for plugin development?". Maybe I am missing something, e.g. special arguments for Eclipse?
This seems all pretty normal. The error message is since the run configuration is specifing a workspace and when you start a second instance using the same workspace it is locked and considered in use.
What I usually do when testing a plugin is to create a run configuration (click "Run...") where I disable all the plugins I wont need when testing. This makes sure that the test starts up a couple of seconds quicker. Make sure you save that run configuration as a *.launch file aswell, that makes it quicker to test the next time. Or it can be used to share the configuration.
There's a lot you can configure in the run configuration, such as eclipse arguments, vm argument, if you want environment variables set, etc. So be sure to experiment a little.
In your run configuration. Main tab->Workspace Data ->Location text box add this:
${workspace_loc}/../runtime-EclipseApplication${current_date:yyyyMMdd_HHmmss}
Note the suffix ${current_date:yyyyMMdd_HHmmss} by this every time you launch your application new workspace will be created. So you will not get any error message saying workspace is locked.
But be careful as the folder .metadata will be different for different instances as their work-spaces are different. Thus preferences stored/retrieved by different instances are NOT in sync.
You are probably missing one important point: Eclipse supports the Java hot code replacement. Therefore in many cases you can modify your Java code while your application Eclipse instance is running, save the code and continue without restarting.
If hot code replacement is not possible, Eclipse will tell you, so you always know whether the editing changes are applied to the running instance.
This works best with more recent versions of the JVM, so consider upgrading to the latest Java 7 version, even if you write code to be compliant with Java 1.5 or 6.
I am trying to use eclipse kepler for Java EE 7.I already installed JBoss Tools and added JBoss Wildfly successfully as a server. However my changes are not automatically deployed. Is there anyway the app can be deployed automatically just as when using glassfish?
Using Eclipse, click twice on your WildFly Server to edit the following properties:
Publishing: choose "Automatically publish after a build event". I like to change the publishing interval to 1 second too.
Application Reload Behavior: check the "Customize application reload ..." checkbox and edit the regex pattern to \.jar$|\.class$
That's it. Good luck!
Both #varantes and #Sean are essentially correct, but these answers are not full.
Unfortunately the only way in a Java server environment to have full, zero-downtime hot deployment is to use paid JRebel or free spring-loaded tool.
But for small project there are some ways to speed up work by partial hot-deployment. Essentially:
When enabled option Automatically publish when resource change
then changes inside *.html, *.xhtml files are immediately
reflected as soon as you refresh the browser.
To make hot deployment work for *.jsp files too, then you should
inside ${wildfly-home}/standalone/configuration/standalone.xml
make following change:
<jsp-config/>
replace with:
<jsp-config development="true"/>
restart the server and enjoy hot deployment of web files.
But when modifying *.java source files, then only partial hot deployment is possible. As #varantes stated in his answer, enabling Application Reload Behavior with regex pattern set to \.jar$|\.class$ is an option, but has serious downside: whole module is restarted, thus:
It takes some time (depending on how big is a module).
Whole application state is lost.
So personally, I discourage this solution. JVM supports (in debug mode) code-swapping for methods' bodies. So as long as you are modifying only bodies of existing methods, you are at home (zero downtime, changes are reflected immediately). But you have to disable automatic publishing inside server settings otherwise the application's state will still be destroyed by that republish.
But if you are heavily crafting Java code (adding classes, annotations, constructors) then unfortunately I can only recommend set publishing into Never publish automatically (or shutdown server) and when you finish your work in Java files, then restart by hand your module (or turn-on server). Up to you.
It works for small Java projects, but for bigger ones, JRebel is invaluable (or just spring-loaded), because all approaches described above are not sufficient. Also because of such problems, solutions like Rails/ Django /Play! Framework gained so huge popularity.
I am assuming you are using the latest version of Wildfly (8.0 Beta 1 as of writing).
In the standalone.xml config file, look for <jsp-config/>. Add the attribute development="true" and it should hot-deploy. The resulting config will look like this:
<jsp-config development="true"/>
Add attributes (development, check-interval, modification-test-interval, recompile-on-fail) in configuration file in xPath = //servlet-container/jsp-config/
<servlet-container name="default" default-buffer-cache="default" stack-trace-on-error="local-only">
<jsp-config development="true" check-interval="1" modification-test-interval="1" recompile-on-fail="true"/>
</servlet-container>
(It works in WildFly-8.0.0.Final)
Start server in debug mode and It will track chances inside methods. Other changes It will ask to restart the server.
I've got a Android AppEngine Connected Project I'm trying to build using GWT2.4 RequestFactory and Objectify on my Eclipse IDE.
Apparently I need to run the RequestFactory Validation Tool because I'm using ServiceName and ProxyForName annotations (these are required especially when working on the Android client side). My problem is the Eclipse can't validate it and the solution provided at http://code.google.com/p/google-web-toolkit/wiki/RequestFactoryInterfaceValidation#IDE_configuration is enough to make me rip my eyes out.
Since I'm working on a Windows machine, the shell script provided is not very useful. Trying to run Validation Tool from a cmd propt returns the error message:"This tool must be run with a JDK, not a JRE"
Can someone explain how this Tool is supposed to be run? Is there a way to use it as an External Tool in eclipse?
Normally if you follow carefully the instructions in the link you show, and run the GWT Development Mode from Eclipse, the Validation should be done automatically at the time you access the development URL with your browser.
For the record, I've actually had some problems with it, but launching the application several times maked it work.
Well, I ran into the same problem as well. When I tried annotation processing (under Java Compiler-> Annotation processing )was being disabled. So RequestFactoryDeobfuscatorBuilder was not being generated. Try enabling that and rebuilding your project.
I've just recovered from two days of hunting this bug down in a project that used to run validation properly but stopped.
In my case I had a new-ish generic BaseRequestContext and a specific sub-interface that extended it. My parent interface declared a method that didn't match the Locator's exactly (e.g. getThing(T) vs get(T)) and this wasn't reported as an error but did stop the validation tool from completing.
Apt is also removed in Java 8 : http://openjdk.java.net/jeps/117 . So beware.
Switching back to Java 7 will fix the issue if you are using Java 8.
I understood why the error happens sometimes in a project: the compiler was complaining it cannot find the directory .apt . But when I tried to create it manually it was not possible (under windows). I think the validation tool mutes the exception of not being able to create the directory: try renaming .apt in your validation tool calls (do a text search in your project)
I recently attempted to set new breakpoints in eclipse to debug service side code in GWT. For some reason eclipse refused to see the breakpoints or the new code changes I had made. In the debugger it would open up what appeared to be an ear file from somewhere. Even though I had deleted the old ears, compiled and redeployed the new ear files. We are using GWT 2.1, JBoss 4.3, java 1.6 and Eclipse Helios. Finally, when I created a new environment with the code from scratch it started working. Any ideas as to what was holding on to the old code? BTW, I had rebooted my machine and restarted eclipse, but it also didn't make any difference.
Thanks,
James
Current state of debugging GWT apps is ... well not really good. Sometimes it's incredibly slow (development mode), sometimes lot of rubbish stays at webserver.
This might not solve your problem directly, but here are some advices from me:
Writing new client code (/client) at GWT means refreshing browser
Writing new server code means "Reloading web server". You have little yellow "refresh" button in Eclipse in "Development Mode" tab. This should reflect all the changes done at server side.
Embedded Jetty works usually well with GWT debugging. If you are not doing something jboss-server-specific, it should also work fine at production server. Just make sure your unit tests pass ;-)
You can ofcourse debug GWT application on external server, see this section of documentation (I guess you do on JBoss)
Be sure to remove all old files when reloading web server. It happened to me, that sometimes there were some weird old mixed up files (I was using Tomcat though). So you might want to write own clean script.
You must be absolutely sure that your serever code even launched! Use lot of GWT.log() at client side, that will ensure you in this. Don't worry, GWT.log are ommitted in production mode.
Be sure to inspect client-side page, it sometimes help to find out that your server code didn't manage to launch.
Log every public void onFailure(final Throwable caught) { of your AsyncCallbacks to get more info.
Don't use Google Chrome in development mode. It's MUCH slower than Firefox.
Otherwise, if you're using most recent version of your application, Eclipse must stop at breakpoint correctly.
I think JBoss was somehow caching things in it's temporary files and then I had forgotten about adding source in. This may be a JBoss thing as I don't recall seeing it with other application servers before.
So after I cleared out the cache, what got me thinking about the source was the fact that eclipse would stop on the breakpoints in the debugger that I had just set, but I couldn't see the source files.
Prior to this I was apparently hitting the breakpoints in the cached files and I couldn't alter them by setting new breakpoints. That was the root cause of the issue. Then by adding in the source from the ear, I got the debugger in sync with the code and it started working fine.
I'm ramping up on Vaadin and I'm getting this javascript alert whenever I try and run the demo apps.
GWT module 'com.vaadin.terminal.gwt.DefaultWidgetSet' may need to be recompiled
I've tried cleaning the project to no avail.
As I said, I'm ramping up so I'm sure there's some simple step I'm missing or a concept I haven't grasped.
I don't know anything about Vaadin, but there's a more general context in which this error occurs:
So long as you're testing in Eclipse, the dynamic coding of your app is still real Java coding being run in a JVM. This coding is made available through debugger that's accessible via a socket. You get a URL that looks like this:
http://127.0.0.1:8888/MyApp.html?gwt.codesvr=127.0.0.1:9997
with this codesvr thing being your eclipse-hosted debugger process for your Java code.
Before your app can run standalone, GWT has to translate your Java code to JavaScript; separate versions of the code are produced for each browser type (Firefox, WebKit, Opera, ...) and language that you want to support. Only once this is done can you access your app the usual way via
http://127.0.0.1:8888/MyApp.html
After weeks of running my app only in Eclipse, I'd managed to forget about the compiling-for-browsers step and wondered about the message. The way to fire up the compiler, if you're not using the Ant task, is to hit Google|GWT Compile in the project's context menu. That done, the JS in your app gets fleshed out and your app can run without Java on the client side.
And of course the message goes away.
It is a warning not an error. Does the app work? Otherwise you have to recompile the Vaadin widgetset. These might help too: http://vaadin.com/directory/help/using-vaadin-add-ons
Often this message meens:
you're missing the ?gwt.codesvr=127.0.0.1:9997 parameter in the URL (or have misspelled it).
your module uses the xs linker <add-linker name="xs" />. This is a known limitation and will be fixed in the future: Issue 4232: Allow Development Mode to work with XS Linker
You may need to clear the browser cache. It is possible that the compiled js that the browser is using is not the js that has most recently been compiled.
In Chrome you can see if the cached js is being used in the developer tools windows (ctrl + shift + i). In the size column it will say (from cache) instead of the actual size. You can then right click and clear the browser cache. ctrl + r to reload and the error should be gone.
Carl Smotricz is absolutely right.
Just Cleaning and Build Project on the topmost menu doesn't work.
You must use "Google | GWT Compile" on the context menu generated when right-clicking on your GWT project, prior to deployment.
The error may not be about not-adding "?gwt.codesvr=127.0.0.1:9997" at the end of host web page if he or she tried to deploy the GWT-based webapp on WAS external to Eclipse.
Server restart did the job for me.
I had tried clearing cache, clean and rebuild .. but i was still getting the same warning message.
Server restart made it reload all the stull from the latest compiled war.
It was a hit and trial and i am glad it worked :) :)