Java – Rename or Move a File

1. Overview

In this quick tutorial, we’re going to look at renaming / moving a File in Java – first using JDK 6, then JDK 7 with NIO, Google Guava and finally the Apache Commons IO library.

This article is part of the “Java – Back to Basic” series here on Baeldung.

Further reading:

How to Copy a File with Java

Take a look at some common ways of copying files in Java.

Read more →

Introduction to the Java NIO2 File API

A quick and practical guide to Java NIO2 File API

Read more →

File Size in Java

Examples of how to get the size of a file in Java.

Read more →

2. With JDK 6

Let’s start with the plain Java, JDK6 solution:

@Test
public void givenUsingJDK6_whenMovingFile_thenCorrect() throws IOException {
    File fileToMove = new File("src/test/resources/toMoveFile_jdk6.txt");
    boolean isMoved = fileToMove.renameTo(new File("src/test/resources/movedFile_jdk6.txt"));
    if (!isMoved) {
        throw new FileSystemException("src/test/resources/movedFile_jdk6.txt");
    }
}

In this example – the file to be moved does exist, as well as the target directory.

Note that renameTo() only throws two types of exceptions – SecurityException – if a security manager denies writing access to either the source or to the destination, and NullPointerException – in case if parameter target is null. If the target does not exist in a file system – no exception will be thrown – and you will have to check the returned success flag of the method.

3. With JDK 7

Let’s now look at how we can do the same using NIO and JDK 7:

@Test
public void givenUsingJDK7Nio2_whenMovingFile_thenCorrect() throws IOException {
    Path fileToMovePath =
      Files.createFile(Paths.get("src/test/resources/" + randomAlphabetic(5) + ".txt"));
    Path targetPath = Paths.get("src/main/resources/");

    Files.move(fileToMovePath, targetPath.resolve(fileToMovePath.getFileName()));
}

In JDK7 the NIO package was significantly updated, and the Path added – this provides methods for convenient manipulation of File System artifacts.

Note that, similarly to the previous example – both the file and the target directory should exist.

4. With Guava

Next – let’s take a look at the Guava solution:

@Test
public void givenUsingGuava_whenMovingFile_thenCorrect()
  throws IOException {
    File fileToMove = new File("src/test/resources/fileToMove.txt");
    File destDir = new File("src/test/resources/");
    File targetFile = new File(destDir, fileToMove.getName());

    com.google.common.io.Files.move(fileToMove, targetFile);
}

Again, in this example, the file to be moved and the target directory need to exist.

5. With Commons IO

Finally, let’s take a look at a solution with Apache Commons IO – probably the most simpler one:

@Test
public void givenUsingApache_whenMovingFile_thenCorrect() throws IOException {
    FileUtils.moveFile(
      FileUtils.getFile("src/test/resources/fileToMove.txt"),
      FileUtils.getFile("src/test/resources/fileMoved.txt"));
}

This one line will, of course, allow both moving or renaming – depending if the target directory is the same or not.

Alternatively – here’s a solution for moving specifically, also enabling us to automatically create the destination directory if it doesn’t already exist:

@Test
public void givenUsingApache_whenMovingFileApproach2_thenCorrect() throws IOException {
    FileUtils.moveFileToDirectory(
      FileUtils.getFile("src/test/resources/fileToMove.txt"),
      FileUtils.getFile("src/main/resources/"), true);
}

6. Conclusion

We looked at renaming in these code snippets, but moving is, of course, the same, only the target directory needs to be different.

And there you have it – 5 quick solutions for moving a File in Java.

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