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Trouble reading/writing file from relative path

I've been trying to read and write to a file under my resources directory in my project. However, regardless of what I seem to do it doesn't allow me to do so.
This is my project hierarchy for reference:
Out of all these:
Paths.get("memes.txt")
Paths.get("resources/memes.txt")
Paths.get("/resources/memes.txt")
...
None have worked. What am I doing wrong?

Is it a Maven project ?
Try this :
//Get file from resources folder
ClassLoader classLoader = getClass().getClassLoader();
File file = new File(classLoader.getResource(fileName).getFile());
Ref : https://www.mkyong.com/java/java-read-a-file-from-resources-folder/

Your application can be packed as .jar file - a zip format.
There, or in the built classes directory should be memes.txt. A so-called resource, and in case of a jar not really a file system file. But is located on the class path.
URL url = getClass().getResource("/memes.txt");
InputStream in = getClass().getResourceAsStream("/memes.txt");
The path is relative to the package directory of the class, or absolute as above.

Try it using "../resources/memes.txt" with ".." you go up one directory from your current file (i assume that you are using the code in SwearTest.java)

unable to read config.properties in java with jar file

I'm new to java , i have file named config.porperties
i put it in this path /home/user/workspace/myproject/config.properties
but when i submitted the jar file after packaged it i got that it cannot find this file
java.io.FileNotFoundException: config.properties (No such file or directory)
the code
FileInputStream finputstream = new FileInputStream(
"/home/user/workspace/myproject/config.properties");
prop.load(finputstream);
but there is no error in the code i think the problem with jar file that it couldn't read the path !
Hope i can find help , THANKS

I am not sure what happend during "but when i submitted the jar file after packaged it". Your code still tried to load home/user/workspace/myproject/config.properties. So check whether that file exists and is readable.
If you want the file to reside on a different path - you have to change your code as the path is hardcoded.
if you expect the config.properties to be packaged within the jar and loaded from there, change your code to something like
InputStream input = getClass().getResourceAsStream("/classpath/to/my/file/config.properties");
Watch out: Again you are hardcoding a path but you can ensure the file will reside at that location within the jar.

Load a file outside of a Jar

I have a folder called lib that contains all my Jar files and in one of the Jar files class, I have a main method which is called by a batch file. In the same folder location as my lib, I have another folder structure path/to/a/resource/myresource.txt
How can I load this file from a class inside the Jar file? I tried the following and both resulted in null:
getClass().getResource("path/to/a/resource/myresource.txt")
getClass().getClassLoader().getResource("path/to/a/resource/myresource.txt")
Any ideas? Even with an absolute path, it failed! Any suggestions?

You can use:
getClass().getResourceAsStream("path/to/a/resource/myresource.txt")
However, for this to work, you need to add the path '.' to the Class-Path entry of the JAR's MANIFEST.MF file.
http://docs.oracle.com/javase/tutorial/deployment/jar/downman.html

Two things you tried are used to read files from class-path since this folder is not on your classpath you can read it directly with any of the java File IO classes.

File file = new File("C:/folder/myFile.txt");
or if you know the relative path:
File file = new File("../../path/myFile.txt");

Your path seems not to be precise enough. Further, this question has been worked before.
Have a look here:
How to Load File Outside of, but Relative to, the JAR?
How to get the path of a running JAR file?

You can either load the file from file system
new FileReader(relativeOrAbsoluteFilesystemLocation)
or you can add the directory in question to your classpath:
java -cp "lib/*;lib" ...
and then use your original method.
(Unix uses : rather than ; as classpath separator)

How to specify relative file path in Java file so that it can still work after the file is put in jar file?

Suppose I have a Java class that needs to access a file with absolute path
/home/gem/projects/bar/resources/test.csv:
package com.example
class Foo {
String filePath = ????? // path to test.csv
String lines = FileInputStream(new File(filePath).readAllLines();
}
Where the path to Foo.java is /home/gem/projects/bar/src/com/example.
Of course I cannot specify absolute path to the resource file. This is because jar file will be distributed as library for any clients to use in their own environments.
Assume the resource file like test.csv is always in the same path relative to project root. When a jar is created containing Foo.class, this jar also contains test.csv in the same relative path ( relative to project root).
What is the way to specify relative path that would work no matter where the project bar is moved to? Also how can I create a jar file (which can be in any location) so that the path to the resource file test.csv would still be correct.
To keep things simple, I have used invalid Java API ( readAllLines() which reads all the lines and return a string containing entire file content. Also not using try/catch).
Assume csv file can be read as well as written to.
I hope this makes it clear now.

Put the test.csv file into the src folder and use this:
Foo.class.getResourceAsStream("/test.csv")
To get an InputStream for the file. This will work wherever the project is moved, including packaged as a JAR file.

Example:
ProjectX\src\Test.java
ProjectX\resources\config.properties
If you have the above structure and you want to use your config.properties file, this is how you do it:
InputStream input = new FileInputStream("./resources/config.projects");
In this example you don't have to worry about packaging your source into jar file. You can still modify your resources folder anytime.

Use getResource(), as shown here.

Java path to support both IDE and generated JAR

I have an issue with path names in my code. Let's say I have a main class:
com.test.LoadFile.java
Similarly I have a myxml.xml file under com.test. Meaning that the Java file and XML file are under same package.
Can somebody suggest how, when I do (inside LoadFile)
File file = new File("???/myxml.xml")
What should the path be, to support both:
Eclipse IDE code (after including the above code into a single Java project)
and
Run the main LoadFile class outside of the IDE (in a JAR file)
What should I use as the value of the path variable to include in the generated project JAR?

You can read the XML file using getResourceAsStream(), as long as it's in the CLASSPATH:
InputStream is = LoadFile.class.getClassLoader().getResourceAsStream("/myxml.xml");
EDIT: If you are packaging into a .jar, you must specify the complete path of the resource from the jar's root folder using "/" at the beginning of string