FATAL: password authentication failed for user "[username]"

conn = database('dbname','username','password','org.postgresql.Driver',
    'jdbc:postgresql:dm-userdb.geomar.de:users:ssl=true&sslfactory=org.postgresql.ssl.NonValidatingFactory&');

install.packages("rpostgres")
library(RPostgreSQL)
drv <- dbDriver("PostgreSQL")
con <- dbConnect(drv, host = "dm-userdb.geomar.de", dbname="users", tty = "NULL", user="****", password = "******", port = "5432")

% Add jar file to classpath (ensure it is present in your current dir)
%javaclasspath('postgresql-9.0-801.jdbc4.jar');

% Username and password you chose when installing postgres
props=java.util.Properties;
props.setProperty('user', 'username');
props.setProperty('password', 'password');
props.setProperty('ssl','true');

% Create the database connection
driver=org.postgresql.Driver;
url = 'jdbc:postgresql://databaseURL/dbname';
conn=driver.connect(url, props);

dbConn = com.allied.pgmex.pgmexec('connect',[...
    'host=<yourhost> dbname=<yourdb> port=<yourport> '...
    'user=<your_postgres_username> password=<your_postgres_password>']);