Logstash Confuguration error

*error: java::org.postgressql.Driver not loaded

input {
jdbc {
# Postgres jdbc connection string to our database, mydb
jdbc_connection_string => "jdbc:postgresql:/localhost:5432/mydb"
# The user we wish to execute our statement as
jdbc_user => "postgres"
# The path to our downloaded jdbc driver
jdbc_driver_library => "c:\logstash\postgresql-42.2.2.jar"
# The name of the driver class for Postgresql
jdbc_driver_class => "org.postgresql.Driver"
# our query
statement => "SELECT * from contacts"
}
}
output {
stdout { codec => json_lines }
}