在Java中如何重命名文件的路径保持不变？

Question

So I finally changed the name of file1 to another name. However what makes me frustrated is that the path remain unchanged!Could you please tell me why and how to deal with it since I always need the handler of file1 for further operation?Here is my sample code:

import java.io.File;
import java.io.IOException;

public class TestFile {
volatile private static File file1;
volatile private static File file2;

public static void main(String[] args) throws IOException {
    file1 = new File("D:\\work\\triangle\\src\\original\\test1.java");
    file2 = new File("D:\\work\\triangle\\src\\original\\test2.java");
    File tmpFile;

    String file2name = file2.getAbsolutePath().toString().replace("\\", "/") + ".bak";
    System.out.println(file2name);

    String file1name = file1.getAbsolutePath().toString()
            .replace("\\", "/");
    System.out.println(file1name);

    tmpFile = new File(file2name);
    if (!file1.renameTo(tmpFile)) {
        System.err.println("file1->file2name-bak");
    }
    System.out.println("file1\t"+file1.getAbsolutePath().toString());
    System.out.println("tmpFile\t"+tmpFile.getAbsolutePath().toString());

}
}

and I get those output:

D:/work/triangle/src/original/test2.java.bak
D:/work/triangle/src/original/test1.java
file1   D:\work\triangle\src\original\test1.java
tmpFile D:\work\triangle\src\original\test2.java.bak

How can the file1 and tmpFile yield different path?

Answer 1

You are misunderstanding what a File is.

A File denotes a file name / path, not the name / path of a specific file. So, when you use a File to rename a file, the pathname stored in your File object does not change. A File object is immutable.

Then is there any way to change them both?

No. The name / path encoded in a File object does not change, and cannot be changed. If you don't believe me, check the source code that is shipped with your JDK.

(The pathname state of a File is represented by the String-valued path attribute. The only places where path is assigned are the constructors, and the readObject method.)