java中的.txt文件的路径

Question

I work with NetBeans IDE an I have a .txt file saved in src/myapp folder. If I run from the IDE, this recognise my

File file=new File("src/myapp/mytext.txt");

But if I build the jar file and double click it or launch it from command line I get this error:

java.io.FileNotFoundException: src\myapp\mytext.txt

I could insert absolute path, but how can I run my jar independently by the position of my project in the computer?

Answer 1

You can obtain the file path indepently of its position with the following:

ClassLoader classLoader = getClass().getClassLoader();
String path = classLoader.getResource("mytext.txt").toString();

Answer 2

Java is expecting to find the file relative to your working directory. So by hardcoding the file in src/myapp/mytext.txt you are expecting the user of your application to have the file under the same folder structure.

If you are expecting the file to be at the same level of your jar file, you can just use ./mytext.txt . Do not put your mytext.txt under the src in your project. That is for sources you want to compile and/or bundle inside your jar file. In NetBeans move it outside the /src folder, that way when you run the program from your IDE or when you run it externally from your Jar file you find the file at the same level.

If you want the user to be able to specify the location himself of the file, you can also read the command line arguments (the arguments to your public static void main(String[] args) ).

Answer 3

没有这样的问题

File file=new File("./src/myapp/mytext.txt");