[Demonstration 1]

[Buggy Method]
@EventHandler
public void onPlayerRespawn(PlayerRespawnEvent event) {
    if (isActive(event.getPlayer()) && !isExpired(event.getPlayer())) {
        Bukkit.getScheduler().scheduleSyncDelayedTask(MagicSpells.plugin, new Runnable() {

            public void run() {
                removeTransform(event.getPlayer());
            }
        });
    }
}

[Buggy Hunk]
removeTransform(event.getPlayer());

[Patch]
turnOff(event.getPlayer());

[Demonstration 2]

[Buggy Method]
public static void saveToFile(File file, GunData data) {
    if (!file.exists())
        try {
            file.mkdir();
            file.createNewFile();
        } catch (IOException e1) {
            e1.printStackTrace();
        }
    FileOutputStream fout;
    ObjectOutputStream oos;
    try {
        fout = new FileOutputStream(file);
        oos = new ObjectOutputStream(fout);
        oos.writeObject(data);
        oos.flush();
        fout.close();
        oos.close();
    } catch (FileNotFoundException e) {
        e.printStackTrace();
    } catch (IOException e) {
        e.printStackTrace();
    }
}

[Buggy Hunk]
file.mkdir();

[Patch]
new File("weapons/").mkdir();

[Demonstration 3]

[Buggy Method]
private void handleStaticClasses(String currentLine) {
    String[] methods = getMethodsFromCurrentLine(currentLine);
    Package[] packages = Package.getPackages();
    for (Package pack : packages) {
        String fullClassName = pack.getName() + "." + methods[methods.length - 1];
        Class<? extends Object> clazz = null;
        try {
            clazz = Class.forName(fullClassName);
            fillAllMethodsAndProperties(clazz, GroovyMethodOption.STATIC);
            showSuggestions(clazz, GroovyMethodOption.STATIC);
        } catch (ClassNotFoundException e1) {
            // Just try with the next package if the current fullClassName does not fit any classes
        }
    }
}

[Buggy Hunk]
} catch (ClassNotFoundException e1) {

[Patch]
} catch (ClassNotFoundException ignored) { //NOSONAR