Selecting a file in another directory for a bufferedReader

问题

I have an initialization file (initialize.java) that pulls in data from fileInput.txt using a fileInputStream, but both of them are in different directories.

Project/library/initialize.java
Project/resources/text/fileInput.txt

my code in initialize.java is:

FileInputStream fstream = new FileInputStream("/resources/text/fileInput.txt");

But the file cannot be read. I've also tried

FileInputStream fstream = new FileInputStream("./resources/text/fileInput.txt");

But that didn't work too.

How can I access the txt file and what's the difference between using "./resources" and "/resources"?

Thanks for reading this.

回答1:

The difference is huge. On linux/unix/macos the path starting with / starts from root directory. The path starting with ./ or without starting from current application directory. Call

System.out.println(new File("."). getAbsolutePath()) to check where you are?

回答2:

FileInputStream fstream = new FileInputStream("resources/text/fileInput.txt");

Tried this?

回答3:

"./resources/text/fileInput.txt" or "resources/text/fileInput.txt" works, but "/resources/text/fileInput.txt" doesn't.

Note: This is valid if the folder named "resources" is located under the root directory of your project.

回答4:

As the other answers suggest, the path you pass to FileInputStream depends on the OS and also if the path is a relative or an absolute path. Another way of reading the file is to use Class.getResourceAsStream() instead. e.g.

InputStream is = this.getClass().getResourceAsStream("/resources/text/fileInput.txt")

For the above to work, you need to have the parent folder of /resources in the classpath. For more information on how getResourceAsStream works, see SO question

来源：https://stackoverflow.com/questions/9679867/selecting-a-file-in-another-directory-for-a-bufferedreader