Web Service Java on OpenShift using Tomcat 6 (JBoss EWS 1.0)

I'm trying to create a Web Service in JAVA to be consumed by an Android application. I need to use a Cloud technology, and only found OpenShift free and best recommended for now ... Well, I've already created my project in Eclipse. I already have all the tools. I already sent the project to OpenShift, etc. The problem is as follows: (Note: I'm a beginner)

I created a connection class with the database:

package conectaMySql;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;

public class ConectaMySql {

    private static final String URL = "link do MySql dado pela OpenShift";
    private static final String USER = "login do MySql dado pela OpenShift";
    private static final String SENHA = "senha do MySql dada pela OpenShift";

    public static Connection obterConexao() throws SQLException{

        try{
            Class.forName("com.mysql.jdbc.Driver");     
        }
        catch(ClassNotFoundException e){
            e.printStackTrace();
        }
        return DriverManager.getConnection(URL, USER, SENHA);
    }
}

I created another class with the following data:

package classesDao;

import java.sql.Connection;
import java.sql.PreparedStatement;

import classes.*;
import conectaMySql.*;

public class AdministradorDao {

    public boolean insertAdmin(Administrador admin){

        try {
            Connection conn = ConectaMySql.obterConexao();

            String queryInserir = "INSERT INTO Administrador VALUES (?, ?)";

            PreparedStatement ppStm = conn.prepareStatement(queryInserir);

            ppStm.setString(1, admin.getLogin());
            ppStm.setString(2, admin.getSenha());

            ppStm.executeUpdate();

            conn.close();
        } catch (Exception e) {
            e.printStackTrace();
            return false;
        }

        return true;
    }

}

Disregarding the MVC concept, lol ... How can I make this class available as a service? I researched a lot on the internet, but I do not handle English very well (I know I'm chipped, and the translation tool helped me damn good), but unfortunately I did not find anything concrete. I saw some things about web.xml, etc ... But I'm still in the dark! And now, who can help me?