Error accessing PostgreSQL using Eclipse Windows 10 [duplicate]

I am in the process of learning Java and PostgreSQL. I am running Windows 10 with JRE 10, my IDE being Eclipse Oxygen 3a. I had written the following code:

import java.sql.Connection;
import java.sql.DriverManager;

public class PostgreSQLJDBC {
   public static void main(String args[]) {
      Connection c = null;
      try {
         Class.forName("org.postgresql.Driver");
         c = DriverManager
            .getConnection("jdbc:postgresql://localhost:5432/testdb",
            "postgres", "123");
      } catch (Exception e) {
         e.printStackTrace();
         System.err.println(e.getClass().getName()+": "+e.getMessage());
         System.exit(0);
      }
      System.out.println("Opened database successfully");
   }
}

It successfully compiles. However, it gives me the following error

java.lang.ClassNotFoundException: org.postgresql.Driver

In following the advice given in Stack Overflow, I have downloaded postgresql-42.2.2.jar and placed within C:\Program Files\Java\jre-10.0.1

I then edited my system variables and added "C:\Program Files\Java\jre-10.0.1" into it. However I still get the same error. Please help