Create separate method to call activity

I created a script where I intend to call separate activities

But it is not working

package com.example.john.new_login;

import android.content.Context; import android.content.Intent;

import com.example.john.new_login.login.Cadastro; import com.example.john.new_login.login.RecuperaSenha;

/ **  * Created by John on 12/09/2017.  * /

public class Botoes_Login {

private static Context context;

public static void Registro() {
    Intent registro = new Intent(context, Cadastro.class);
    context.startActivity(registro);
}

public static void RecuperaSenha() {
    Intent recuperasenha = new Intent(context, RecuperaSenha.class);
    context.startActivity(recuperasenha);
}

public static void Login() {
    Intent login = new Intent(context, Login.class);
    context.startActivity(login);
}

}

What would be the correct way to create a class for this?