No Suitable Driver Found (Postgres JDBC) : java.sql.SQLException: No suitable driver found for jdbc:postgresql://rds-service:5432/postgres

Question

I am trying to make a simple connection to my postgres database on CentOS 7 ec2 instance. Here is my PostgresqlConnect.java file:

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

public class PostgresqlConnect {
    
    private final static String url = "jdbc:postgresql://rds-service:5432/postgres";
    private final static String user = "root";
    private final static String password = "test123";
    
    public static void main(String[] args) {
        try{
            Connection connection = DriverManager.getConnection(url, user, password);
            if (connection!= null) {
                System.out.println("Connected successfully!");
            }
            else {
                System.out.println("Failed to connect.");
            }
        } catch (SQLException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
    }

}

My steps to run/compile are as follows:

> javac -cp /usr/share/java/postgresql-jdbc.jar PostgresqlConnect.java`

> java PostgresqlConnect

And I get this:

-------- PostgreSQL JDBC Connection Testing ------------
java.sql.SQLException: No suitable driver found for jdbc:postgresql://rds-service:5432/postgres
    at java.sql/java.sql.DriverManager.getConnection(DriverManager.java:702)
    at java.sql/java.sql.DriverManager.getConnection(DriverManager.java:228)
    at PostgresqlConnect.main(PostgresqlConnect.java:15)

I installed the postgresql-jdbc rpm package as such: yum install postgresql-jdbc. I think I'm linking the library when I add -cp /usr/share/java/postgresql-jdbc.jar to my javac -cp /usr/share/java/postgresql-jdbc.jar PostgresqlConnect.java command so not sure where I'm going wrong. My javac and java versions are both 14.0.2.

Answer 1

The correct way to run it and see "Connected successfully!" would be

> javac PostgresqlConnect.java
> java -cp /usr/share/java/postgresql-jdbc3.jar PostgresqlConnect.java