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Exported jar finds some files (not all) even though the paths are the same [duplicate]

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I'm trying to export a runnable jar in Eclipse, but I need it to include some other files necessary for running my program
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Closed 8 years ago.
When I run my program from eclipse, it shows up fine, the images from Resources\ show up, as do the sounds from the same place, and the text files are found properly. However, when I export my jar, and copy the resources into it with 7Zip, the images will work, but the sounds and the text files can't be found, even though they're in the same folder, with the same path used to find them in my code. I can fix this by putting a folder next to the jar file named Resources, and put everything in there, but I'd like to know why just putting it in the jar file only worked for the images, and how I can get it to work with the text and audio files as well.
An example to show you what I mean:
File inventory = new File("Resources/inv.txt");
threadpath = "Resources/threads.wav";
enemy1 = new Sprite(new Texture("Resources/miniForestGolem.png"));
When I run it in eclipse, all three work fine, but when I export it, and put the resources folder in the jar file, only the image works.
Edit:
I know how to include my resources, and have done so, I'm asking about how/why some of the resources aren't able to be accessed, even after adding them in.

Ok, from your comments we can infer the difference between executing it from eclipse and executing it from a .jar.
From eclipse: it works, because all that new File(...) find an actual file in Resources/
From the .jar: it won't work, since there is no file in a relative ./Resources/ path from the execution path of the application.
The way to make it work is the next:
Make sure Eclipse recognizes Resources/ as a source folder (right-click on project properties, Java Build Path, and add it as a source path)
Look for a replacement for your API methods that, instead of File objects, use InputStreams. Once you have it, retrieve all your resources as InputStreams taken from the classpath. If you are inside MyClass.java, do this: MyClass.class.getClassLoader().getResourceAsStream("Resources/inv.txt"), etc.
What you have achieved by doing this: instead of File objects built on actual operating system files, you will be retrieving InputStreams read straight from your java application classpath. This way, you can package them into a jar, or into a WEB-INF/classes directory inside a web application, or a library folder in some application servers... wherever you like as long as it is into the application classpath. I would do this if I had to package your application in a portable and usable way.

Launch .jar with config outside of jar, but be able to do it from ANY current directory

I've been wrestling with a particular problem. I have a Java program in a .jar file, and I have a lib directory and a config directory outside of the .jar, but in the same directory as the jar itself exists in.
I am trying to reference config/foo.config from within the code. Referencing it as a relative file works if I'm in the same directory as the jar. I've also tried using getResourceAsStream and making sure config is in the classpath.
So far, so good, but I also have to be able to launch the .jar from any directory.
So, if my structure is like so:
/prog/util/myprog/myprog.jar
/prog/util/myprog/config
/prog/util/myprog/config/foo.config
/prog/util/myprog/lib
(and a whole bunch of 3rd party jars within lib)
How do I correctly set up the classpath in my Manifest file so that config can be referenced?
The classpath in my manifest looks like so:
Class-Path: config/ lib/jar1.jar lib/jar2.jar (etc)
I am currently using getResourceAsStream("/foo.config").
This all works if I am in the /prog/util/myprog directory and run:
java -jar myproj.jar
However, I cannot, say, be in /prog and run:
java -jar util/myprog/myprog.jar
When I do this, the config file cannot be found.
How do I solve this issue?
EDIT: Some additional notes based on comments/suggestions, though I'm not sure this is feasible:
1) We can't use an absolute path for the file system, we don't know where the program will be stored, just that the config directory will be in the same directory as the jar.
2) I would like to be able to have something that works both when the code is jar'd, but also would work not-jar'd such as when I'm running in debug mode in Eclipse. At that point, the config directory is a sibling of the src, bin, and lib directories.
EDIT Part 2: Ok, between a colleague and myself, we came up with the following:
String configDirectory = new File(QueueMonitor.class.getProtectionDomain().getCodeSource().getLocation().getPath()).getParent() + "/config";
When we are in Eclipse and running in debug mode, the File object points to the bin directory, so getting the parent then appending "/config" works for our needs during development/testing.
Likewise, from a .jar file, the File object points to the jar itself, so getting the parent and appending "/config" gives us what we need as well.
I'm a little hesitant, though. I'm wondering if there's some potential problem or unintended consequence that I am not seeing in this solution. Any thoughts on that?

You should be able to use the Finding the path to a jar from a Class inside it? technique to find the location of your jar. From there it's just a matter of climbing in/out of folders.

Java read a folder from project base directory

I have a maven project with typical project structure. At the base of the project, I have a directory names res that has some resources (> 500 MB).
I am trying to use
this.class().getClassLoader().getResourceAsStream("res/xxx")
this code fragment to read from that folder, but it returns a null resource stream.
I have a few workarounds below, but none of these are acceptable due to reasons explained below.
I can move the folder to {base}/target/classes, and it will be read, but it will also get cleaned when I do a mvn clean. Hence, this approach doesn't work. For some reason, specifying the path as ../../res/xxx also doesn't work.
I can move the folder to {base}/src/resources, but then it will get copied to target/classes and the jar. Hence this is also not acceptable.
Though I am open to trying some other java APIs, I may have to use the class loader mechanism only as there is some external library component that is also trying to access the res folder using the similar approach.
Is there some way I can read the res folder from projects base directory? Is there some setting in pom.xml file that can help me with that?

Use this.class().getClassLoader().getResourceAsStream("/res/xxx") and then you will be reading from the root of the classpath irrespective of the actual file/folder location in windows or Linux. This is actually one of the safest ways to read files especially when you do not know how your application will eventually be deployed.
It means though that your classpath must include the parent of res and that res/ must be copied over when you deploy your app
Otherwise, if you want to use relative paths, try this snippet (taken from this SO answer):
String filePath = new File("").getAbsolutePath();
filePath.concat("path to the property file");

If you use this.class().getClassLoader().getResourceAsStream("/res/xxx"), it is going to try to load resources from the classpath. If that's not want you want to do, you're going to need to specify an absolute path.
Resource on Classpath
If you don't want the resource built into your JAR, I'd suggest having a different maven project with the file in it, under the src/main/resources directory. This will create a jar file with the file in it, which will be ~500MB.
After this, you can include a dependency on this project in your project containing your application code. This will then be able to reference it from the jar file using getResourceAsStream(...).
If you don't want this large jar file to ship with your application, make sure you mark the dependency with <scope>provided</scope>.
File from Absolute Path
You will need to take the file location as a parameter in your main method, and then use new File("C:\\path\\to\\your\\file.txt") and then use a FileReader to read it in.

Java resources - Use file far off in directory tree

I have a newbie Java question.
I had to make suite of J/DBUnit tests for some stored procedures we use in SQL Server. These tests use some XML files in a couple of sub-directories that I originally had placed in the same directory as my Java project.
Anyway, upon checking these tests in, our SVN manager wanted to keep the .java files in one part of the tree, and resources (like the XML files and required JARs) in another part of the tree.
So, my tests had originally referenced the XML files with a relative path which doesn't work now.
My question is:
Can I make the directories with my XML files available with the CLASSPATH (I hope so).
Assuming that works, how do I reference a file in my code that was included this way?
If I shouldn't be using the CLASSPATH for this, I'm open to other solutions.

Forget calsspath. Provide your tests with a parameter/configuration which defines the root dir for the relative paths of the XML files.

Using the classpath is no problem, the standard maven project layout looks like the following:
src
main
java
resources
test
java
resources
target
classes
test-classes
The compiler compiles src/main/java to target/classes, the resources of src/main/resources are copied to the target/classes folder, similar for the tests. If the tests have a classpath containing classes and test-classes, all works fine.
How is your project layout is, how is it build?

No, you should not use CLASSPATH in this instance since it is used by Java. However, you can use a similar approach by loading a value from an environment variable or configuration file which indicates the directory where the XML files are stored.

You can do this without making any changes to your classpath. The idea is to store the resource files in a separate directory, but have them copied to a directory in your classpath when you run your build process.
Here is an example configuration:
source Directory is ${basedir}/src/main/java
resource directory is ${basedir}/src/main/resources
In your build script, copy both the .java files and the resource files (.xml) to a directory in your classpath, say:
${basedir}/target/classes
Your test code runs against the target dir. The target directory is not checked in to SVN, keeping your SVN admin happy, and you don't have to make changes to your code.

How to access Jar file located within source folders?

in my Java project I am using an H2 in-memory database, for which I have to load the JDBC driver when I initialize my application. I want/need to load the H2 .jar file dynamically, so I do the following:
String classname = "org.h2.Driver";
URL u = new URL("jar:file:libs/h2.jar!/");
URLClassLoader ucl = new URLClassLoader(new URL[] { u });
Driver d = (Driver) Class.forName(classname, true, ucl).newInstance();
DriverManager.registerDriver(new DriverShim(d));
When I put the H2 .jar file into a "libs" folder outside my Java source code folder (that is, in Eclipse, this "libs" directory is on the same level as the "src" folder), then this approach works fine. However, unfortunately I have to put this H2 .jar file into a folder within the source code folder tree, but below the main class folder.
For example, my Java package structure looks like this in Eclipse:
<project>/src/my/app/MyApp.java // main class of my application
<project>/src/my/app/sub/package/h2.jar // how to access this?
<project>/libs/h2.jar // loading from here works
I know this is stupid, but unfortunately I have to work with this strange setup. But what I don't know: how can I edit my Java code (listed above) in order to work with this setup?
EDIT: This has to work outside Eclipse as well, so adding the JAR file to the Java Build Path in Eclipse is no option for me.
EDIT2: I already tried to load "jar:file:my/app/sub/package/h2.jar!/", but that did not work for me.
Thanks in advance for all helpful ideas!
Kind regards, Matthias

In some frameworks referring to files inside JARs can be done using the classpath: prefix. I doubt URLClassLoader supports it natively, but it's worth a try (e.g. classpath:/my/app/sub/package/h2.jar). But since that doesn't work with URLClassLoader, here are other ways:
One way to do it would be to write your own ClassLoader which reads the JAR file from classpath (using getResourceAsStream), uncompresses it (using ZipInputStream) to memory (e.g. a map of byte arrays) and loads the classes from there.
Another, slightly easier way, is to read the JAR file from classpath and write it into a temporary file. Then you can use the plain URLClassLoader to load classes from it. This has the disadvantage that the file must be written to a file and the file probably cannot be removed until the JVM exits (unless using Java 7 or higher).
I'm using the second approach (copying to a temp file) in one project, though I'm using it to launch an external process. I would be curious to hear why you have such a requirement. If it's just a matter of having the whole application in one JAR, there are numerous simpler methods for achieving that (Maven Assembly Plugin, Maven Shade Plugin, Jar Jar Links, One-JAR to name a few).
No it's not a homework, but an online build system that uses my classes under my/app/* and several other classes (not from me) to automatically build the whole solution. Anyway, I can't give you more details on the internals of this system, as I don't know them. As said, I simply have to live with it, and that is why I am asking here...
Sounds like you are working in a WTF environment (does it have a name?), so here are some ways to start hacking around it:
Find out more about your environment, especially absolute file paths of the following: directory where the source files are saved, directory where the generated .class files are saved, and the current working directory when the program is run.
If you can get any kind of output of what your program prints during runtime, you can put into your application some debug code where you use File.listFiles() to crawl the machine's directory trees. If you can get output only from what happens when compiling, it might be possible to execute your own code during compile by creating your own annotation processor (apt is part of javac since Java 6), though I'm not sure whether the annotation processor must be compiled first separately.
The working directory can be read from the user.dir system property and the location of class files can be probably gotten from the java.class.path system property (unless custom class loaders are used). There is no guarantee that a JAR file in the source directory would be copied to the classpath, so you might need to do some looking around.
Then when you know the file path of the JAR file, then you can get an URL to it using new File("path/to/h2.jar").toURI().toURL() which you can then pass to URLClassLoader.
If nothing else works, upload the source code of the libraries and compile them together with your project.
In the long run, try to replace the WTF build environment with one that uses a standard build tool (such as Maven) and a common CI server (such as Jenkins). It's normal for projects to have lots of library dependencies, so you shouldn't need to hack around a build environment to use them.