How do I find Oracle 12c connection URL?

Question

I am using eclipse and java to connect to an oracle 12c database. But every time I run through the process, I get a connection fail error that reads:

java.sql.SQLException: Invalid Oracle URL specified

Here is what my code looks like:

import java.sql.*;

public class JdbcConnection {
    public static void main(String[] args) {
        try {
            Class.forName("oracle.jdbc.driver.OracleDriver");
            Connection con = DriverManager.getConnection("jdbc:oracle:thin@localhost:1521:xe", "username", "password");
            Statement statement = con.createStatement();
            String sql = "select * from employees";
            ResultSet rs = statement.executeQuery(sql);
            while (rs.next())
                System.out.println(rs.getInt(3) + " " + rs.getString(2));
            con.close();
        } catch (Exception e) {
            System.out.println(e);
        }
    }
}

I am using a windows 7 sp1 Ultimate (64 bit)
CPU: i5 2.85 ghz
RAM: 8GB

Oracle is installed in a separate hard drive (in the same computer).

EDIT:
I have tried the first suggestion from this post: How do you find out the Oracle database's URL? and I get an error that says:

ORA-00928: SELECT KEYWORD MISSING...

This error occurs when I run the oracle "SQL DEVELOPER" application on the startup menu and type the suggestions from post above. Note: I want to connect to the database from eclipse and query it programatically. Is there a way to find out what the correct connection URL is? Please help.