Hey there, my name is ***** ***** welcome to Just Answer. It sounds like your mac is not liking your admin password ***** install the java runtime file correct?
The first and easiest thing to try is to reset your password ***** "users and groups" from within the system preferences but you might have already tried this so here is a another way to try:
Every Mac has a main user account called “root,” which is the system account that’s used to launch the essential background services required for your Mac to operate. While this account is generally hidden and inaccessible, you can quickly get to it for its administrative capabilities by booting your Mac into single-user mode.
To proceed you’ll need to know the short name of the account for which you would like to reset the password, and then perform the following steps:
mount -uw /
launchctl load /System/Library/LaunchDaemons/com.apple.opendirectoryd.plist
Please let me know what happens. If this in any reason helped with your issue, please consider rating me.