FileWatcher.java

package prsw3;

import java.io.IOException;
import java.nio.file.FileSystems;
import java.nio.file.Files;
import java.nio.file.Path;
import java.nio.file.Paths;
import static java.nio.file.StandardWatchEventKinds.ENTRY_CREATE;
import static java.nio.file.StandardWatchEventKinds.ENTRY_DELETE;
import static java.nio.file.StandardWatchEventKinds.ENTRY_MODIFY;
import java.nio.file.WatchEvent;
import java.nio.file.WatchKey;
import java.nio.file.WatchService;
import java.util.logging.Level;
import java.util.logging.Logger;
import java.util.stream.Stream;

class FileWatcher implements Runnable {

    private Main main;
    private String root;

    public FileWatcher(Main main) {
        this.main = main;
        this.root = this.main.sourcepath;
    }

    @Override
    public void run() {
        Path rootp = Paths.get(root);
        WatchService watcher;
        try {
            watcher = FileSystems.getDefault().newWatchService();
        } catch (IOException ex) {
            Logger.getLogger(Main.class.getName()).log(Level.SEVERE, null, ex);
            return;
        }
        try (Stream<Path> paths = Files.walk(rootp)) {
            paths.forEach(p -> {
                if (watchp(p)) {
                    main.enqueueFileChange(new FileChange(p));
                }
                if (Files.isDirectory(p)) {
                    System.out.println("adding watch for directory: " + p);
                    try {
                        p.register(watcher, ENTRY_CREATE, ENTRY_DELETE, ENTRY_MODIFY);
                    } catch (IOException ex) {
                        Logger.getLogger(Main.class.getName()).log(Level.SEVERE, null, ex);
                    }
                }
            });
        } catch (IOException ex) {
            Logger.getLogger(Main.class.getName()).log(Level.SEVERE, null, ex);
        }
        while (main.isRunning()) {
            try {
                WatchKey k = watcher.take();
                k.pollEvents().stream().map((evt) -> (WatchEvent<Path>) evt).forEach((pevt) -> {
                    Path relPath = pevt.context();
                    Path dir = (Path) k.watchable();
                    Path absPath = dir.resolve(relPath);
                    if (watchp(absPath) || pevt.kind() == ENTRY_DELETE) {
                        main.enqueueFileChange(new FileChange(pevt, dir));
                        System.out.printf("CHANGE %s, dir %s, file %s\n", pevt.kind().toString(), dir.toString(), relPath.toString());
                        if (Files.isDirectory(absPath)) {
                            if (pevt.kind() == ENTRY_CREATE) {
                                try {
                                    System.out.println("adding watch for directory: " + absPath);
                                    absPath.register(watcher, ENTRY_CREATE, ENTRY_DELETE, ENTRY_MODIFY);
                                } catch (Exception e) {
                                }
                            }
                        }
                    }
                });
                k.reset();
            } catch (InterruptedException e) {
            }
        }
    }

    private static boolean watchp(Path p) {
        String s = p.toString();
        return Files.isDirectory(p) || s.endsWith(".txt") || s.endsWith(".xml") || s.endsWith(".java");
    }
}