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javafilefile-rename

java File renameTo()

first of all renameTo() works fine, the problem is after it has been renamed, the path of File f is still the old one instead of the new one, in other words File f is unusable, and has to be changed. but how should I do it?

    ArrayList<File> list = new ArrayList();
    public void myfunction() {
        // some code to fill list

        for (File f:list){
            changeName(f);
            System.out.println(f.getName());  // this print the old name
        }
    }

    public void changeName(File f){
    File newFile = new File(new SimpleDateFormat("yyyyMMdd_HHmmss").format(f.lastModified())+".txt");
        f.renameTo(newFile);
        f = newFile; //this line here doesn't work
    }
}
Solution

  • It is because in JAVA variables are passed by value. If you want to see new content then return newFile, instead of f = newFile; statement.