Java 8 List All Files in Directory

List All Files in Directory

Files.list Method Return a lazily populated Stream, the elements of which are the entries in the directory.

We Can use the stream operations to find Specific Files, List file matching certain criteria, List filenames in sorted order etc.

Example 1: List All Files in Directory

List All Files in Directory

public static void main(String[] args) throws IOException {		
		
		try(Stream<Path> list = Files.list(Paths.get("C:\\Program Files\\"));)
		{
		  list.forEach(System.out::println);			
		}		
	}

Example 2: List All Files in Directory Starting with A

List All Files in Directory Starting with A

public static void main(String[] args) throws IOException {

		try (Stream<Path> list = Files.list(Paths.get("C:\\Program Files\\"))) {
			List<String> fileList = list.map(path -> path.getFileName()
					.toString())
					.filter(name -> name.startsWith("A"))
					.sorted()
					.collect(Collectors.toList());
			fileList.forEach(System.out::println);
		}

	}
   

Example 3: List Files Only

List Files Only

public static void main(String[] args) throws IOException {

		try (Stream<Path> list = Files.list(Paths.get("C:\\Program Files\\"))) {
			List<String> fileList = list.filter(path->path.toFile().isFile())
					.map(path -> path.getFileName().toString())
					.collect(Collectors.toList());
			fileList.forEach(System.out::println);
		}

	}
   

Example 4: List Directory Only

List Directory Only

public static void main(String[] args) throws IOException {

		try (Stream<Path> list = Files.list(Paths.get("C:\\Program Files\\"))) {
			List<String> fileList = list.filter(path->path.toFile().isDirectory())
					.map(path -> path.getFileName().toString())
					.collect(Collectors.toList());
			fileList.forEach(System.out::println);
		}

	}
   

Example 5: List Hidden files Only

List Hidden files Only

public static void main(String[] args) throws IOException {

		try (Stream<Path> list = Files.list(Paths.get("C:\\Program Files\\"))) {
			List<String> fileList = list.filter(path->path.toFile().isHidden())
					.map(path -> path.getFileName().toString())
					.collect(Collectors.toList());
			fileList.forEach(System.out::println);
		}

	}
   

Note

Files.list Method Return a lazily populated Stream for the directory.
It does not return Stream for the nested directory. For that, we Can use File.walk . Will discuss that in next chapter.