I have a project which i need to be made as an executable jar file. I used clean and build option in project, right-click menu and it built normally. The problem is, I cant run the executable jar file in project's dist folder (giving an error saying it could not find the main class, but believe me, I have given the main class correctly). I tried this using an example project (Just a Jframe) and gave me the same error. It can be solved by lowering the JDK version into JDK 6 (current version is JDK 7)but for that i have to do major changes in my actual project (such as replacing all switches into for loops and replacing all multi catches in to single catches...etc). is there any way to make executable jar without changing JDK version?
My netbeans version is 8.0.2
Assuming you have a "private static void main" in you main class.
If you open (not run) the Jar file in the dist folder.
Open the MANIFEST.MF file in /META-INF folder.
Do you see something like Main-Class: com.satra.satra_finacials.view.main.MainFrame ?
If not you can define your main class in Menu File -> Project Properties (Satra_Financials) -> Category Run -> Main Class TextField
Related
Using Java8, Eclipse Mars 4.5
I have a simple Maven project with a pom and a single java file, in a folder. I do the File -> Import -> Existing Maven Project -> Point to my folder. Eclipse does its thing sucessfully creates the project (no errors). But with somewhat of a complex folder structure that I am able to edit (with some difficulty). My project file structure is:
Project
/classes
/pkg
/.class
/src
/pkg
/.java
I originally see my java file (but not in the /src), I see all my dependent jars. After some doing (open/new etc) I am able finally compile my java class- I see all the generated class files.
But I am unable to run it. I do have my main class specified in the eclipse run configuration.
I don't have the Run As enabled.
I try run java application, get error:
Could not find or load main class 'myclass' (I do have the main method)
If I try Maven build (M2 the red icon), initially I got 'no goal specified' error, added <defaultGoal>install</defaultGoal> to the pom. I do get BUILD SUCCESS
But still no run? What am I missing.
I went the maven project route to simplify, but
Thanks
This problem was finally solved by conforming (submitting) to the default file structure of the eclipse/maven project- <classpathentry kind="src" output="target/classes" path="src/main/java">. I re-created the file structure (as this) put/copied my .java and .classes in those directories - it ran fine finally.
I could see this problem when I opened the .classpath file - it had the original /classes and /src directory and not he one I had edited in eclipse (as I indicated in my Question). Even though I was actually successfully compiling into my /classes.
I would certainly not expect this behavior, there is clear edit option for /src and /classes and it should take effect- but maybe not.
Another observation to add- when I look at my run configuration - I see the correct class but eclipse does not show the location. So one would never know.
So long story short it finally worked after much frustration and effort and loss of a couple of days (And I just had exactly one java file to compile and run - wondering how much pain would be if I had a few more).
I am not a regular eclipse user (any longer) so some of it would be getting used to etc - but some of these quarks need to be taken care of (It is the No1 tool)
The structure is as follows:
Actually deployed module is EAR.
EAR contains WAR module, and WAR module contains another JAR module.
In this last JAR, there are some generated classes and their parent folder is also used as source folder. Its path is "target/generated-sources/java".
The problem that is killing me, is that the deployed application throws ClassNotFoundException on server start, and the classes in question are the generated ones.
Now the trick:
if I explicitly change the Deployment Assembly in WAR project in Eclipse not to contain JAR project as "project", but as an archive from the JAR's project "target" folder, JBoss sees the generated classes and starts.
This solution however works only until next eclipse maven project update, so manual edit of deployment assembly is not really a solution.
Any ideas how to deploy or reorganise packages correctly?
OK, seems I have found the solution.
I looked through the build-path of the mentioned JAR file and saw that the entry Output folder pointed to target/test-classes.
After changing this entry to target/classes the application deploys and starts without any missing generated classes.
This is what worked for me:
Expand the 'target' folder of your maven project inside Eclipse (Project Explorer View);
Refresh it (F5);
Right click on your project on 'Servers' tab, then select "Full Publish";
Start your JBoss.
I had to enforce the JBoss Tool "Full Publish" to get an updated version of my target folder by Refreshing it manually on eclipse.
I don't know why but sometimes the Publishing from maven projects (even Full Publishes) do not copy classes from the target Project as it is in the file system. Maybe it's using some outdated memory info or some cache...
Anyway, this is what works for me.
After an update to Eclipse 4.15 and JBoss tools I got this problem too.
My solution: project -> properties -> Java Build Path --> Source
There my Output folder from my source was linked to project/target/classes, I changed this to project/target/project-projectversion/WEB-INF/classes
When I looked into the standalone JBoss folder I saw the folder structure of my source, but the classes where missing, when I changed the output folder the classes pop up and everything worked like before.
I am pretty sure the update made the problems.
As soon as I create a java file in eclipse it creates the corresponding class file in the bin directory which I assume is because eclipse compiles any java file as soon as it is created?Am I right?And later does it compile any java project again when I run it?
If you have Project > Build Automatically checked then Eclipse compiles your Java code as you go.
The code is not compiled again when you Run the program.
You are right for the first part (eg: a *.class in the bin directory).
Eclipse does incremental compilation (eg: almost like compile as you type).
For the second part, I don't understand your question.
It will happen in case Build Automatically option is checked (Menu-->Project-->Build Automatically). If you uncheck that option .class file will not be created when you save java file.
I have an eclipse plug-in working fine within eclipse environment.
I wanted to export it into a jar file, so I chose Export > Deployable plug-ins and fragments.
I could get a jar file, but an error was reported.
Opening the log file, it reports that I have 1242 problems (191 errors, 1051 warnings). This is some copy from the error log.
2. ERROR in /Users/LSclipse/src/lsclipse/LSDiffRunner.java (at line 61)
import edu.washington.cs.induction.OnePipeLineScript;
^^^
The import edu cannot be resolved
----------
3. ERROR in /Users/LSclipse/src/lsclipse/LSDiffRunner.java (at line 261)
OnePipeLineScript.getMatchingForRefFinder(projName, proj1, proj1Loc
^^^^^^^^^^^^^^^^^
OnePipeLineScript cannot be resolved
Why I got errors? I had 2049 warnings, but no error when I compile the plugin in eclipse IDE.
ADDED
The main project references two other projects, and references many external libraries. I attach the package view and Java build path.
There were multiple issues involved for this problem. However, the core issue was that the project apimatching and originanalysis were not eclipse plugins but just java projects. As a result, those two projects were not included in the final jar file to break the build.
Symbolic linking the two projects into the main project
I solved this issue by symbolic link the src directory into the main eclipse plugin project.
ln -s /workspace/seal/edu.ucsc.originanalysis/src /LSclipse/originanalysis
ln -s /workspace/seal/edu.ucsc.apimatching/src /LSclipse/apimatching
From the Java Build Path/Source tab, I added those two included projects as source. Eclipse Java Missing required source folder: 'src'
Now I have eclipse plugin jar file without error.
Then click F-5 to refresh the project explorer and check they are java src directory.
Select the included projects in Build tab.
Updating bin.include and source.. in build.properties tab is important. One should understand that in bin.include the ordering is also critical. lib/cdtparser.jar and lib/cdtcore.jar should be placed prior to the user of them - origin analysis/.
Copying jar files for included project into main project
I also had to copy some jar files in those projects file into the main project, and select them in Binary Build tab.
And add tim in Runtime/Classpath tab.
Select the JavaSE-1.6 in Execution Environments.
I have lots of "Must Override a Superclass Method" errors. With the hint from this post - 'Must Override a Superclass Method' Errors after importing a project into Eclipse , I removed the J2SE-1.5 to resolve this issue.
You can not add third party libraries into class path of Java when developing a plug-in. It is the way to build standard Java application, but plug-in is a kind of OSGi bundle that has itself rule for class loading.
The correct way is adding third party libraries into the class path of your plug-in.
Add below declaration into MANIFEST.MF of your plug-in,
Bundle-ClassPath: lib/log4j-1.2.7.jar,
xml-apis.jar,
...
Check those links [1], [2] for understanding it.
This is what have a question on and see as potential solutions to potential problems.
Is this class comfing from a referenced jar or is it in the actual plugin edu.washington.cs.induction.OnePipeLineScript;
You seem to have a lot of soure folders and wondering if your build.properties file is showing any warnings and that you also have this defined for each of the source folders in your build.properties source.. = src/
Your external jar libraries appear to be in a folder that is of type source which is not correct. It should be a non-source folder (which you can tell a source folder by the package icon decorator) and you should make sure in your manifest editor that for runtime you have the lib checked so that it includes the jars in the build. To unmark it as a source folder select the drop down menu in your navigator view go to filters and uncheck .resources which will then show the .classpath file in that file you will see the folder to be kind="src" (i believe) remove that.
Somehow it also looks like you have linked source folders which is a practice I would not suggest and am not sure if that will cause problems when exporting the plugin. If you can avoid linked source folders that would be better.
Also it seems like you are confusing java build path configuration for plain java applications with plugins running in OSGI which is not configured through java build path but your manifest.editor So as a rule of thumb if its a plugin don't even bother trying to configure the java build path because OSGI is different, that could be causing issues as well
Select "Use class files complied in the workspace" in Options works for me.
I'm learning to use Springsource Tool Suite (STS) and the Spring framework for development. I am trying out the Amazon AWS SDK for eclipse and decided to install it into STS. When I follow create a new AWS project, it puts the .java file under src instead of src/main/java and when I try to build that, it says
"There is no main"
or something like that.
But, when I move the AwsConsoleApp.java and the AwsCredentials.properties to src/main/java then (default package), I can run the file as a Java application.
My question is, what is the difference between src/main/java -> default package and src -> main. I've attached an image to clarify things:
Answer:
Each Java project in Eclipse (and STS as well), has associated build path, where it is specified, which folders in the project contains java classes. Thus, the difference between src/ and src/main/java is that src/main/java is configured as a folder, containing java classes (or source folder in Eclipse terminology), while src/ folder just contains the source folder.
More information can be found in Eclipse Help.
I'm not sure what has caused that your Java classes end up in the wrong folder, but this means that they are not in the classpath of the project. So, when you run your application as Java application, it complains that it cannot find main() method (which is the default entry point for any Java application).
Everything comes into place, when you move your classes under the default package in src/main/java: Eclipse finds your Java classes and the main() method.