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how to provide relative path in eclipse while running in tomcat server

I wrote java code using REST which retrieves the employee details like id and name from a saved file. Absolute path is working fine while running the tomcat server, but once i provide relative path tomcat is not finding the file path. I'm using BufferedReader to read from the file.

Eclipse server plugin will compile the java sources into binary class files and put it into a work dir, so the relative path will not working. The quickest way to make it work is to put your files into the source directory. Then Eclipse server plugin will copy that file to the classes folder in your work directory. Then you can use relative path to read it.

Eclipse showing incorrect project path

I have a maven web project in eclipse. I need to get the project's path, actually have to get list of files under src\main\resources\someFolder in project.
Tried String dataDir = "src\\main\\resources\\someFolder";, on running this directory structure is created inside eclipse folder like F:\softwares\eclipse\eclipse\src\main\resources\someFolder. Same when using / instead of \\.
Tried System.getProperty("user.dir")and new File(".").getAbsolutePath(), they return F:\softwares\eclipse\eclipse.
I need to access the project folder in my workspace F:\workspace\Project\src\main\resources\someFolder
But when created a core java app and used System.getProperty("user.dir")and new File(".").getAbsolutePath(), I am getting project path in workspace, F:\workspace\Project. This src\\main\\resources\\someFolder also works fine then.
Why this odd behavior from eclipse?

As mentioned here the directory user.dir is the place where the JVM is started. As web applications are mostly jar/war/ear packages placed somewhere within the folder of the server eclipse handles them in a different way because the behaviour of such a web application is different. You cannot expect to have file access from outside the jar/war/ear file. Within the jar/war/ear file everything from within src/main/resources will be available just by using getResourceAsStream as described in many other stackoverflow articles. This way you mustn't use src/main/resources/myfile.txt but myfile.txt.
Don't try to guess or use what the user.dir / JVM/server start folder is!

Running .jar File Java 8

I've run .jar files before, but I've encountered a "different" situation, and I'm not sure what to do. I'd appreciate if someone could help me out.
Previously, I programmed with Java 6 and Eclipse Juno exported all my programs to runnable jar files. I'd get a .jar file that I could run by just double clicking on it. The files always looked something like this (note the jar file icon):
Recently, I wrote a program in Java 8 with Eclipse Luna (Release 4.4.0) and exported it to a runnable jar file, and I got something different (note the different file icon):
It no longer runs when I double click it. Instead, my computer uncompresses the jar, as it would a zip file. I tried running it from terminal. I cd'd to the directory and typed
java -jar graph3D.jar
I got the following error message:
Error: Unable to access jarfile graph3D.jar
After uncompressing the jar file, I found a folder named META-INF with the manifest file, MANIFEST.MF in it. It was the only file that seemed to resemble an executable file. Do I have to do something with that?
Could someone explain how I can run the second jar file graph3D.jar? Is it something new with Java 8, or something different about Eclipse Luna, or something else?
(Both programs run fine in Eclipse, by the way)
Thanks for your time and help.
Edit:
Below was the dialog box Eclipse displayed if anyone is interested.
Selecting "Use .jar;.zip" makes the filename "graph3D.jar;.jar;*.zip" .
Selecting "Use .zip" makes the filename "graph3D.jar;*.zip"
Selecting "Cancel" doesn't let you go forward.
You'd have to manually delete the extra file extension.

Somehow when you exported the file, the filters for the file dialog box (*.jar;*.zip) got attached to the filename, which is graph3D.jar;*.jar;*.zip, not graph3D.jar. Java can't find it because it doesn't have the name you supplied. Rename the file and pay close attention next time you export; either you fat-fingered something, or you're triggering a significant bug that needs fixing.

I recommend that you will access the build folder after you've built your project on the IDE under your project folder (in your workspace) and copy both the libraries folder and the .jar and post them wherever you want the program to be "installed", you'll then have an executable jar that should run smoothly without problems, just as I said don't forget the lib folder.

I think there is nothing new in Java 8 related with the running jar, I guess you need to check the the Eclipse export issues, it seems your classes are missing from your second jar file.

Exporting processing to a jar file

I've been working on a processing application using ControlP5 and Twitter4j. I want to have my project run from a single jar file from any operating system. Basically I want to package up my application. My application uses images. I've been browsing for more than an hour, but I cant find how to do this. Any suggestions?
using
processing 2
twitter4j3
Thanks in advance!

I dont know if you can directly do it from the Processing IDE however, if export your sketch to a Java applet then locate the .java the the sketch folder you can use this in conjunction with Eclipse to export to a jar file.

So, I know that this post is very old but if you are still looking for a solution, or to other people that see this thread, it's relatively simple.
Export the project
In the folder with the exported project (something like application.windows64), navigate to lib and find core.jar and project name.jar (you need to have file name extensions visible)
Rename the files to .zip files
Extract core.jar to whatever folder
Extract project name.jar into the same folder (make sure you don't do it into a subfolder)
Click yes if it asks if it wants you to replace a file (if it doesn't you extracted the files incorrectly)
Delete core.jar and project name.jar
If the project uses images, move them into the same folder as all the other files
Select all of the files in the folder, right click, hover over send to and select compressed (zipped) folder
Rename the .zip file to name of project.jar

This might be old, but i still find other posts about it on processing forums.
This is the best way to run processing project as a jar file.
When exporting application, you will always end up with a lib folder inside exported application(whether for Linux and Windows). For windows, open command prompt(or power shell), you can use right-click+shift and then click on open power shell here.
After that you can run the following command.
java -classpath lib\* DisplayDepthStream
Now DisplayDepthStream is the name of sketch file.
To explain the command, -classpath lib\* tells java to add everything under lib directory to the class path. And DisplayDepthStream is the name of my main class.
Hope this helps~!
Chears

Eclipse project can not reference a file using relative paths

My file is located under the src directory. However, when I try to call it using "src/readme.txt" the file is not found.
In fact, it states that java is looking for "C:\Documents and settings\john\My Documents\Downloads\eclipse-win32\eclipse\coolCarsProject\src\readme.txt".
How do I fix this? I do not want to put in the absolute path all the time.
Do I need to fix the classpath, buildpath, or change the project root, etc? It is not at all obvious from the roughly 1000 settings in Eclipse for a newbie.

First, you have to decide if you want to load the file from the file system, or if the file will in fact be bundled with your application code.
If the former, then you should really think about how your application will be launched when actually deployed, because using a relative file path means that the program should always be started from the same location: a relative path is relative to the location from where the program is started (the current directory). If this is really what you want, then edit your launch configuration in Eclipse, go to the Arguments tab, and set the working directory you want. But the src directory is not where you should put this file, since this will copy the file to the target directory, along with the classes, that will probably be put in a jar once you'll deploy the application.
If the latter, then you should not treat the file as a file, but as a resource that is loaded by the ClassLoader, using ClassLoader.getResourceAsStream() (or Class.getResourceAsStream()). Read the javadoc of those methods to understand the path to pass. If you put the file directly under src, it will be copied by Eclipse to the target directory, along with your classes, in the default package. And you should thus use SomeClass.class.getResourceAsStream("/readme.txt") to load it.

Using paths relative to the current working directory is not a good idea in general, as it's often quite hard to establish what your current working directory will be. In Eclipse, it will be your project folder (unless you set it to something different in your launch configuration), in webapps it will be the webapp's root directory, in a command line app it could be anything.

Try this one:
String filePath = ".\\userFiles\\data.json";
where «.\» is a root for the Eclipse project, «userFiles» is a folder with the user's files inside of Eclipse project. Since we are talking about Windows OS, we have to use «\» and not «/» like in Linux, but the «\» is the reserved symbol, so we have to type «\\» (double backslash) to get the desired result.