Delete Files with same Prefix String using Java

Question

I have around 500 text files inside a directory with a same prefix in their filename say dailyReport_.

The latter part of the file is the date of the fi

Answer 1

Use FileFilter like so:

File dir = new File(<path to dir>);
File[] toBeDeleted = dir.listFiles(new FileFilter() {
  boolean accept(File pathname) {
     return (pathname.getName().startsWith("dailyReport_08") && pathname.getName().endsWith(".txt"));
  } 

for (File f : toBeDeleted) {
   f.delete();
}

Answer 2

or in scala

new java.io.File(<<pathStr>>).listFiles.filter(_.getName.endsWith(".txt")).foreach(_.delete())

Answer 3

You can't do it without a loop. But you can enhance this loop. First of all, ask you a question: "what's the problem with searching and removing in the loop?" If it's too slow for some reason, you can just run your loop in a separate thread, so that it will not affect your user interface.

Other advice - put your daily reports in a separate folder and then you will be able to remove this folder with all content.

Answer 4

You can use a loop

for (File f : directory.listFiles()) {
    if (f.getName().startsWith("dailyReport_")) {
        f.delete();
    }
}

Answer 5

There isn't a wildcard but you can implement a FilenameFilter and check the path with a startsWith("dailyReport_"). Then calling File.listFiles(filter) gives you an array of Files that you can loop through and call delete() on.

Answer 6

I know I'm late to the party. However, for future reference, I wanted to contribute a java 8 stream solution that doesn't involve a loop.

It may not be pretty. I welcome suggestions to make it look better. However, it does the job:

Files.list(deleteDirectory).filter(p -> p.toString().contains("dailyReport_08")).forEach((p) -> {
    try {
        Files.deleteIfExists(p);
    } catch (Exception e) {
        e.printStackTrace();
    }
});

Alternatively, you can use Files.walk which will traverse the directory depth-first. That is, if the files are buried in different directories.