public class MRVCheckBlock extends JavaPlugin implements Listener{
    Logger log = Logger.getLogger("Minecraft");

    @Override
    public void onEnable() {
        getLogger().info("Enabled@");

        Bukkit.getPluginManager().registerEvents(this, this);
    }
    @Override
    public void onDisable(){

    }

    private boolean inter;

    @EventHandler
    public void onInteractPlayer(PlayerInteractEvent e) {
        Block b = e.getClickedBlock();
        if(b.getType()==Material.WOOD_PLATE || b.getType()==Material.STONE_PLATE) {
            inter=true;
            return;
        }
        inter=false;
    }

    @EventHandler
    public void onPlayerMove(PlayerMoveEvent e) {
        if(!inter) return;
        if(e.isCancelled()) return;
        Player p = e.getPlayer();
        double v = p.getVelocity().getY();
        Block b1 = e.getTo().getBlock();

        if(v==-0.0784000015258789) {
            boolean plate;
            if(b1.getType() == Material.WOOD_PLATE) {
                plate = true;
            }
            else if(b1.getType() == Material.STONE_PLATE) {
                plate = true;
            }
            else return;

            if(!plate) return;

            Block b2 = b1.getRelative(BlockFace.DOWN);


            if(b2.getType()!= Material.DIAMOND_BLOCK) {
                return;
            }
            p.sendMessage(v+"");
            p.setVelocity(p.getVelocity().setY(10));
        }
    }
}