I would like to compile my Java program in Eclipse but not to run it. I can't understand how to do it.
How can I compile a Java program to .class files in Eclipse without running it?
You can un-check the build automatically in Project menu and then build by hand by type Ctrl + B, or clicking an icon the appears to the right of the printer icon.
You will need to go to Project->Clean...,then build your project. This will work, even when your source code does not contain any main method to run as an executable program. The .class files will appear in the bin folder of your project, in your workspace.
Right click on Yourproject(in project Explorer)-->Build Project
It will compile all files in your project and updates your build folder, all without running.
In the case that you delete your .class file in Eclipse and then try to build it again from the .java file it will do nothing. If you try to run the .java file without the .class file you will get an error that it can not find the main class.
You will either have to change and re-save the .java file then build it again, or else you have to run Clean on the project then build again.
Try this in your console:
javac {$PathToYourProyect}/*
If you also need any external library, try:
javac -cp {$PathToYourLibrary}.jar {$PathToYourProyect}/*
Right click on the file on package Explorer
Then go to Show in
Under it go to terminal
Eclipse will have a terminal then
Use javac fileName to compile
Go to the project explorer block ...
right click on project name
select "Build Path"-----------> "Configuration Build Path"
then the pop up window will get open.
in this pop up window you will find 4 tabs. 1)source 2) project 3)Library 4)order and export
Click on 1) Source
select the project (under which that file is present which you want to compile)
and then click on ok....
Go to the workspace location of the project open a bin folder and search that class file ...
you will get that java file compiled...
just to cross verify check the changed timing.
hope this will help.
Thanks.
Related
I am constantly facing this error and I have no idea how to fix it.
App.java is not on the classpath of project ss_d36b3017, it will not be compiled to a .class fileJava(32)
I am using Visual Studio Code for writing Java. I have set up the environment variable. javac --version and java --version and giving the expected results in PowerShell. I am using a very simple folder convention than is made by VS Code pallet. It has 1 folder (in drive D:)named project which has 3 folder named lib(This is vacant), src(This has the App.java)<readme.md It has no building tools. Code inside the App.java does not affect the issue.
I need some help.
Try the following two ways to see if question goes away.
Open Command Palette and choose Java: Clean Java Language Server Workspace
Right click the folder src and choose Add Folder to Java Source Path, then reload the window.
advanced Java programmer, newbie to Eclipse (Oxygen.1a Release (4.7.1a)) here.
When I try to run my Java console app [invoking main()], Eclipse doesn't seem to compile the current java file in my editor and copy the class file to the bin directory. Instead, it just runs the same old class file that is already in the bin directory, or if it's not there, complains that "Error: Could not find or load main class MyPackageA.MyClassA". It worked only once, the first time when I created the project and imported the files.
I can edit the java file in a text editor, compile and run it at the command line OK (away from Eclipse). I can even copy the class file(s) to Eclipse's bin directory and 'run' the corresponding java file that's in my Eclipse editor. But it's not the java file that's in my Eclipse editor that is running, nor is it a class file compiled from that java file; it's the class file of the same name that I compiled and copied to the Eclipse bin from elsewhere.
Tutorials and YouTube videos that I have found only seem to show the "happy path" where everything works as one my expect.
Please advise.
I ran Project->Clean... on the project and now it is working; compiles and copies/deploys to the bin directory, executes as expected.
It still gives me an error dialog before executing: "Errors exist in required projects...Proceed with launch?" That doesn't seem to affect the outcome, but I'm worried there be more problems lurking in the shadows.
Thanks to All for your help!
I apologize if this is an absolutely dunce question. I typically use Intellij Idea, and I'm not quite so familiar with Eclipse, so maybe this is part of my problem. I'm trying to compile a jar, I've done the export, as jar file, and checked "create .class files" in the output options, I click finish, and it "compiles" the jar file for me in the output.
I go to check the .jar file (open in Winrar) and the .jar file contains a folder named src, with all the .java source code, and there are no .class files in the .jar file. I figured maybe I could just change the file extension, because I thought maybe it just didn't change the extension, but when I got to view the file, it is clear that it hasn't even been parsed, as it is still in source format.
I receive no compile errors when I try to export it in Eclipse. I do have build errors for the entire project, but I'm not so worried about the entire project, I just wanted to compile one .jar file. And the build errors are not relating to the .jar file I'm trying to build, they are related to other files. Is it necessary to fix every build error to compile one .jar file? I'm just not quite sure why it would "compile" with no build errors, and then not actually compile.
Thank you in advance for any help!
Right click on your project > select Export... > select if your project is runnable or only JAR > check the option "Export Java source files and resources" > Finish
I have this code, in where I have 'jar' file that I use as a library. And in my "src" I have multiple packages with ".java" files in them.
I am highly confused about how to compile and run this program on terminal.
I have attached an image of the directory.
Link: https://www.dropbox.com/s/yfg22v9y78yndan/DirecotryPic.png
Thanks in advance :)
Why do you have a jar file in the src folder??
You should be referencing them from Java build path. Right click on your project -> Java Build Path -> Configure Build Path -> Libraries.
Add your library files here. Not in the src.
From the picture it seems you are using eclipse IDE. Eclipse builds the file automatically. From the Menu bar click Project and make sure you checked Build Automatically.
To run this on the terminal, export this whole project as Runnable Jar and from terminal execute this "java -jar yourproject.jar"
Right click on project -> Export -> Runnable Jar.
Is it what you are looking for???
First of all: JAR files should not be copied to the src folder. As far as I can see DirectoryServer.jar is in it right now.
Secondly: .sh files should be moved to the root of your project too.
You could easily generate Ant buildfiles with Eclipse (Export.. > Ant buildfiles) and then use them from terminal (installing ANT is a must!).
Other option would be to export a runnable JAR directly from Eclipse, then run it from terminal.
I hope it helps! Feel free to ask in comment if you have any more questions!
How to compile and run Java Eclipse Project from command prompt?
How to run a Java Eclipse project from Command Line with java file name only. I don't want to to use class file or jar files generated by Eclipse.
Is it possible?
Even with jar file, I found loading of static file was failing, as FileNotFoundException, how to solve that?
I meant to run like this-
http://www.skylit.com/javamethods/faqs/javaindos.html
First javac then java
Kind of old question I know, but if you want to know command prompt for running Eclipse-based project (i.e the one that Eclipse uses)
Run your project into Eclipse
Goto Debug perspective
(on my screen anyway) Window in top left corner should have a little
'debug' tab.
Right click on name of your project, select Properties at
the bottom of drop-down
Click on the 'Command Line' field (this is what you
probably want).
Press [ctrl]+A & [ctrl]+C to select and copy
Either paste this into command line, or
(what I did) in Windows, create new *.bat text file and paste it in
there ... now double clicking on that file should run your java proj.
Pretty useful if you wanna run something out of eclipse and are lazy like me.
BTW I needed this for exporting project for a uni assignment. Of course, they wanted to see code in *.java files too and above just uses *.class files Eclipse builds on the fly.
To make batch compile your *.java files & then run you need to put together an appropriate javac command before the javaw line you got from process above and adjust accordingly - look at Java Docs for this. Eclipse has done most of hard work with library class paths though (I was using a few libs).
For building you can export an Ant build file. Just right click on the project -> Export -> Ant buildfiles. On the command promt use ant <buildfile> to build the project.
Take a look at this answer: Eclipse: export running configuration for running the eclipse project from the console.
Assumes a project with the following directory structure:
PROJECT_HOME
-> lib (jar files)
-> src (java code)
-> hirondelle (top-level package; no .java files)
-> ante (.java files)
-> deluvian (.java files)
Compiling With javac
PROJECT_HOME>javac -cp lib\* src\hirondelle\ante\*.java src\hirondelle\ante\deluvian\*.java
This compiles in place, and creates .class files beside .java files. If you want to place generated class files elsewhere, use the -d option to put them into an existing directory:
PROJECT_HOME>javac -cp lib\* -d build src\hirondelle\ante\*.java src\hirondelle\ante\deluvian\*.java
If your jars are in various directories, then the classpath is a list delimited by semi-colons:
-cp lib\*;C:\abc\one.jar;C:\xyz\two.jar
For more information refer below links:
Compiling With javac - javapractices
Build Eclipse Java Project from Command Line - Stackoverflow
Select the project and click on File->Export which opens a new window.
From that select Runnablejar option and click next button.
In launch configuration select your main class and in export destination give the path where you want to store the jar file.