I'm exporting runnable jar with a main method that reads testng xml and starts execution, however After exporting, the jar doesn't find xml path, but when I run it through eclipse, it executes fine.
It is searching for xml on the exported location of jar,instead it should be packed within jar itself.not sure why is so.
below is the error.
It is searching for xml on the exported location of jar
No it isn't. Java is looking for that file in the current working directory.
instead it should be packed within jar itself.not sure why is so.
So it should be accessed via the class-resource API, not via a FileInputStream.
I was also getting this problem. You have to place the 'files' in the directory where you have placed the jar file.
Do these changes:
1) Edit your code and write the file's name only where you have put the source location of the file.
2) Then export to .jar file.
3) Put those files (.xml) in the directory where you have placed the .jar file.
It worked for me! I hope it will work for you too.
Related
I have finally completed a program in Java and I have to upload it.
The problem is that I have to upload also the executable .jar file and not only the eclipse project.
The main functionality of my program consists by reading and writing .xml files (for example one file is used to read and add new users), and the files in the project folder are so located:
-Project Name
src
default package
main and all other classes
file1.xml
file2.xml
So the two .xml files are in the root of the project.
My question is: It is better to save the .xml files in the JAR and then writing and reading them from the executable program or it is better to store them in a folder outside the .JAR and reading and writing them as externally files?
It is a good practice to create a folder like that?:
-ProjectName
file1.xml
file2.xml
project.jar
I read in Stackoverflow a lot of people having my same issue and a lot of people doesnt know how to manage this problem properly.
Thank you in advance for the reply :)
Changing files in JAR-files can have all sorts of problems. That starts with simple things such as what should happen when you want to update your program to the newest version? Usually you'd just swap the jar, but then you loose everything you edited so far. You'd need a process to update inside the jar.
Other problems include that for changing the jar file you need to open it, possibly realign contents and rewrite the index which could conflict with the JVM that is reading the jar at the same time causing odd behaviour. On some systems (windows...) the Jar file might even be locked while the application is running and thus you cannot write to it at all.
I'd suggest that you add "default files" (in case that your files are initially not just empty) to you Jar file that represent the initial state. If the application is started you check if the XML files exist in the some normal writable directory and if they don't just copy the default files to that directory. This allows you to deploy still just a single jar file, but once started the appropriate files will be created.
You may read a XML file located inside the executable Jar but it is not possible to update (write) a XML file located inside that executable Jar file. So the best option would be:-
-ProjectName
file1.xml
file2.xml
project.jar
The jar should be kept read-only, the XML "files" inside the jar should be read using getResource[AsStream] (class path). You can use those resources as templates to create a copy in the user's (or application's) directory/sub-directory. For the user's directory:
System.getProperty("user.home")
I have simple Java Application and trying to create JAR to distribute using eclipse.
But when I look inside JAR it doesn't contain the test.txt file. I created JAR as Export>Runnable JAR File
You need to put that file into one of your source folders (such as src). Only those get copied into the jar file (by default).
See the following image:
Choose the file which you want to add in jar file.
I'll try to be clear and concise on this.
i have a jar file of a project which is working perfectly. Now I need to make some changes to the application so i extracted that jar using this command.
jar xf jwire.jar
the files extracted are
META-INF (containing manifest file)
Resources (containing pictures used in application)
Jwire (containg classes and java files)
.classpath
.project
manifest.mf (another manifest file with some other path to main class)
i also added two empty folders src and bin here on somebodys suggestion.
now i'm trying to create the jar file again using all these folders.
Without making any type of changes I'm trying to rebuild this jar using the following
jar cf newjar.jar G:\Project1\project
NOTE:- I am guessing it's the right way to build the file. Please point if it's not right.
G:\Project1\project is the path to above mentioned files and folders.
The jar created using this is of size 729kb while the earlier one had 711Kb and when I run it using the following command.
java -jar newjwire.jar
I get the following message
no main manifest attribute, in newjwire.jar
Next i tried extracting this newjwire.jar file in order to see its manifest file. I got this folder META-INF containing the MANIFEST.MF file. it didn't have the path to the main class , So I edited it and put the modified file back on using the following command
jar uf newjwire.jar META-INF/MANIFEST.MF
when I run this jar, I get the following message
Error: Ivalid or corrupt jarfile newjwire.jar
What am I doing wrong? Am I building the jar file the right way? I used eclipse juno too and it gave the same message to that mainclass is missing. There is a main class consisting the main function. Is this something has to do with My orignal jar having two MANIFEST file.
I hope the problem is understandable. Clear and detailed answers will be appreciated.
you're supposed to update JAR files by jar uf jar-file input-file(s)
see this link: http://docs.oracle.com/javase/tutorial/deployment/jar/update.html
According to this page you need to EITHER have Manifest.txt present when you create or update the JAR, or use the e option to specify the main class. Probably the latter would make more sense in your case.
jar cfe newjar.jar mypackage.MainClass G:\Project1\project
The Netbeans created Jar does not work, but inside the IDE program it works perfectly.
I believe that the main class is set, so I'm not sure what the problem is, I think it might have something to do with the txt files I'm using, in the IDE they are in C:\Users\J\Documents\NetBeansProjects\PointOfSale\src\pointofsale (the text files are with my java files). After building the dist/ jar though the text files are inside the jar with no folders or anything (Jar is in C:\Users\J\Documents\NetBeansProjects\PointOfSale\dist). I this this might be the problem, if its helpful, I access the files using
File file = new File(System.getProperty("user.dir")+"\\src\\pointofsale\\list.txt");
You need to use Class.getResourceAsStream() to load the file. It searches from inside the classpath (and therefore from inside the jar). Now you can't load the list.txt because it doesn't exist in the directory you're specifying, it's inside your jar.
Something along the lines of
getClass().getResourceAsStream("list.txt"); // Or "/list.txt"
Will give you an InputStream you can use to load the file contents.
I am exporting a runnable JAR from Eclipse. When run, it reads in a configuration file and based on this configuration file opens other files also for configuration purposes. However, when I move this JAR to another location it continues to try to use the values in the old configuration file, even though a new configuration file is present. Why does it do this?
The problem may be that the file is included in the Eclipse build path, so when it gets exported that file is built with the JAR. Then, regardless of whatever path is given for the configuration file on the command line, the JAR will use the file that was already packaged inside of itself. (This was my problem. Removing it from the build path resolved the issue.)