I installed IntelliJ Ultimate on a new Mac and remarked that it would not remember database passwords, no matter what:
The specified database user/password combination is rejected:  [Database][JDBC](10100) Connection Refused: [Database][JDBC](11640) Required Connection Key(s): PWD; [Database][JDBC](11480) Optional Connection Key(s): AccessKeyID, AuthMech, AutoCreate, BlockingRowsMode, ClusterID, DbGroups, DisableIsValidQuery, DriverLogLevel, EndpointUrl, FilterLevel, IAMDuration, Language, loginTimeout, OpenSourceSubProtocolOverride, plugin_name, profile, Region, SecretAccessKey, selectorProvider, selectorProviderArg, SessionToken, socketTimeout, ssl, sslcert, sslfactory, sslkey, sslpassword, sslrootcert, SSLTruststore , SSLTrustStorePath, tcpKeepAlive, TCPKeepAliveMinutes, unknownLength
And then I enter my password and all is fine… until the next query. And this gets annoying very quickly because I keep having to copy/paste the password.
It turns out that the link between my Mac Keychain and IntelliJ was not working too well. I just had to head to Preferences and tell IntelliJ to save passwords using KeePass (which is a neat feature by the way) and everything works great again.
What’s the actual problem though? I don’t know. The keychain works well and IntelliJ is awesome. I do suspect the keychain to be guiltier here, as it tends to like nagging me for passwords. Better safe than sorry I suppose. If you know a likely cause, please send me an email.