Coins SQL

public class MySQLCoins {

	private String url_base, host, name, username, password, table;
	private Connection connection;

	public MySQLCoins(String url_base, String host, String name, String username, String password, String table){
		this.url_base = url_base;
		this.host = host;
		this.name = name;
		this.username = username;
		this.password = password;
		this.table = table;
	}

	public void connection(){
		if(!isConnected()){
			try{
				connection = DriverManager.getConnection(url_base+host+"/"+name, username, password);
			}catch (SQLException e){
				Bukkit.broadcastMessage(e.getMessage());
			}
		}
	}

	public void deconnection(){
		if(isConnected()){
			try{
				connection.close();
			}catch (SQLException e){
				e.printStackTrace();
			}
		}
	}

	private boolean isConnected(){
		try{
			if((connection == null)||(connection.isClosed())||(!connection.isValid(5))){
				return false;
			}else{
				return true;
			}
		}catch (SQLException e){
			e.printStackTrace();
		}
		return false;
	}

	private Connection getConnection(){
		return connection;
	}

	public void createAccount(Player p){
		try{
			PreparedStatement sts = getConnection().prepareStatement("SELECT coins FROM "+table+" WHERE uuid = ?");
			sts.setString(1, p.getUniqueId().toString());
			ResultSet rs = sts.executeQuery();
			if(!rs.next()){
				sts.close();

				PreparedStatement sts2 = getConnection().prepareStatement("INSERT INTO "+table+" (uuid, coins) VALUES (?, ?)");
				sts2.setString(1, p.getUniqueId().toString());
				sts2.setInt(2, 10);
				sts2.executeUpdate();
				sts2.close();
			}
		}catch (SQLException e){
			e.printStackTrace();
		}
	}

	public void addCoins(String uuid, int coins){
		try{

			PreparedStatement sts = getConnection().prepareStatement("UPDATE "+table+" SET coins = coins + ? WHERE uuid = ?");
			sts.setInt(1, coins);
			sts.setString(2, uuid);
			sts.executeUpdate();
			sts.close();
		}catch (SQLException e){
			e.printStackTrace();
		}
	}

	public void removeCoins(String uuid, int coins){
		try{

			PreparedStatement sts = getConnection().prepareStatement("UPDATE "+table+" SET coins = coins - ? WHERE uuid = ?");
			sts.setInt(1, coins);
			sts.setString(2, uuid);
			sts.executeUpdate();
			sts.close();
		}catch (SQLException e){
			e.printStackTrace();
		}
	}

	public Integer getCoins(String uuid){
		int coins = 0;

		try {
			PreparedStatement sts = getConnection().prepareStatement("SELECT coins FROM "+table+" WHERE uuid = ?");
			sts.setString(1, uuid);
			ResultSet rs = sts.executeQuery();
			if(!rs.next()){
				return coins;
			}
			coins = rs.getInt("coins");
			sts.close();
		}catch (SQLException e){
			Bukkit.broadcastMessage(e.getMessage());
		}
		return coins;
	}
}