How to list the files inside a JAR file?

Question

I have this code which reads all the files from a directory.

    File textFolder = new File(\"text_directory\");

    File [] texFiles = textFolder.listFiles         


        

Answer 1

I've ported acheron55's answer to Java 7 and closed the FileSystem object. This code works in IDE's, in jar files and in a jar inside a war on Tomcat 7; but note that it does not work in a jar inside a war on JBoss 7 (it gives FileSystemNotFoundException: Provider "vfs" not installed, see also this post). Furthermore, like the original code, it is not thread safe, as suggested by errr. For these reasons I have abandoned this solution; however, if you can accept these issues, here is my ready-made code:

import java.io.IOException;
import java.net.*;
import java.nio.file.*;
import java.nio.file.attribute.BasicFileAttributes;
import java.util.Collections;

public class ResourceWalker {

    public static void main(String[] args) throws URISyntaxException, IOException {
        URI uri = ResourceWalker.class.getResource("/resources").toURI();
        System.out.println("Starting from: " + uri);
        try (FileSystem fileSystem = (uri.getScheme().equals("jar") ? FileSystems.newFileSystem(uri, Collections.emptyMap()) : null)) {
            Path myPath = Paths.get(uri);
            Files.walkFileTree(myPath, new SimpleFileVisitor() { 
                @Override
                public FileVisitResult visitFile(Path file, BasicFileAttributes attrs) throws IOException {
                    System.out.println(file);
                    return FileVisitResult.CONTINUE;
                }
            });
        }
    }
}