public class ExampleMod extends JavaPlugin implements Listener {
    @Override
    public void onEnable() {
        getServer().getPluginManager().registerEvents(this, this);
    }

    @EventHandler
    public void onPlayerDeath(PlayerDeathEvent event) {
        final Player player = event.getEntity();

        getServer().getScheduler().scheduleSyncDelayedTask(this, new Runnable() {
            @Override
            public void run() {
                Location spawn = player.getBedSpawnLocation();

                if (spawn == null) {
                    spawn = player.getWorld().getSpawnLocation();
                }

                player.setHealth(20);
                player.teleport(spawn);

                System.out.println("Attempting to respawn " + player + " to " + spawn);
            }
        }, 20);
    }
}