Logback RollingFileAppender supporting half hour

Logback doesn't support half hour file rolling directly.

So I implement

my own FNATP (File Naming And Triggering Policy) and RollingCalendar as follows:

https://github.com/izeye/samples-spring-boot-branches/tree/logback

Note that the implementation is for half minute to test easily.

You can easily change it for half hour.

I wonder why there's no accessor

for `TimeBasedRollingPolicy`'s `fileNamePattern` and `fileNamePatternWCS`.

I have to do reflection hacks because they are package-private.

I tested a little but not fully so you have to check it before using it in production.

Note I didn't copy separate active file related stuff fully for clarity.

If you need it, you can easily add it as follows:

https://github.com/qos-ch/logback/blob/master/logback-core/src/main/java/ch/qos/logback/core/rolling/TimeBasedFileNamingAndTriggeringPolicyBase.java#L59-L64

If there's any bug, please let me know.

Reference:
http://logback.qos.ch/manual/appenders.html

Aggregate columns in multiple rows into a single column in Oracle

To aggregate columns in multiple rows into a single column in Oracle,

use `LISTAGG` function as follows:

SELECT LISTAGG(id, ',') WITHIN GROUP (ORDER BY id) FROM tb_person WHERE first_name = 'Johnny';

Reference:
https://docs.oracle.com/database/121/SQLRF/functions100.htm#SQLRF30030

Low resolution problem in MacBook Pro when you log in.

You could encounter low resolution problem in MacBook Pro

when you log in like after connecting to a projector.

Then, try to reset NVRAM (non-volatile random-access memory) as follows:

1. Shut down your Mac.
2. Locate the following keys on the keyboard: Command (⌘), Option, P, and R.
3. Turn on your Mac.
4. Press and hold the Command-Option-P-R keys immediately after you hear the startup sound.
5. Hold these keys until the computer restarts and you hear the startup sound for a second time.
6. Release the keys.

References:
https://discussions.apple.com/thread/2353284
https://support.apple.com/en-us/HT204063

Caused by: java.security.cert.CertificateException: No subject alternative names present

When you try to make an HTTPS connection with an unmatched CN (Common Name),

you will get the following exception:

Caused by: java.security.cert.CertificateException: No subject alternative names present

It is not a usual case

but in some case like monitoring, it could be necessary.

You can work around it as follows:

HostnameVerifier hostnameVerifier = new HostnameVerifier() {
@Override
public boolean verify(String s, SSLSession sslSession) {
return true;
}
};

HttpsURLConnection.setDefaultHostnameVerifier(hostnameVerifier);

Reference:
http://stackoverflow.com/questions/10258101/sslhandshakeexception-no-subject-alternative-names-present

Push a local branch to remote in Git

To push a local branch to remote in Git,

do the following:

git push -u origin issue-1

Reference:
http://stackoverflow.com/questions/2765421/push-a-new-local-branch-to-a-remote-git-repo-and-track-it-too