Question

I have two File Object oldFile and newFile and I would like to exchange the corresponding file names. So I rename oldFile to a tmpFile name first. I get the oldFile’s absolute path and append “.bak” for it:

String tmpFile = oldFile.getAbsolutePath().toString()+".bak";
oldFile.renameTo(new File(tmpFile));

The problem is that tmpFile contains the raw string of path,while the constructor of File class treat the ‘\’ as the escape.So the tmpFile may be “D:\oldfile.java.bak”,however what the constructor need is

new File("D:\\oldfile.java.bak");

How can I deal with it?

Answer 1

You have to escape the escapes with .replace("\", "\\") but if you have to do that then realize you don’t have to use \ on Windows. Java supports / just as fine and it doesn’t have these problems. You can do replace("\", "/") and it works just as well.

You also need to read and understand how to create new files in Java. File.createNewFile() is required to be called. Just creating a File object with the constructor doesn’t actual create a file on the filesystem nor does it guarantee that a file at that location exists.