* Introduced hudson.TcpSlaveAgentListener.getAdvertisedHost()

* review feedback

* better error message

* Replace apache base64 with java

* Swap to regular encoder

This refactors usage of Charset::forName on common character sets that
now have an equivalent value in StandardCharsets.

[JENKINS-57993] Avoid printing stack traces for some common agent conditions

(cherry picked from commit dcc395b8)

* Change getInstance() (deprecated) to get()

* Reverting modifications according review

* Changing for use the variable

Co-Authored-By: Nlongngn <vulongvn98@gmail.com>

Minor version annotation update in TcpSlaveAgentListener.java

Amends code added in https://github.com/jenkinsci/jenkins/pull/2082.
java.lang.RuntimeException: Unexpected issues encountered during cleanUp: offset 0, count -1, length 5
	at jenkins.model.Jenkins.cleanUp(Jenkins.java:3319)
	at org.jvnet.hudson.test.JenkinsRule.after(JenkinsRule.java:495)
	at org.jvnet.hudson.test.JenkinsRule$1.evaluate(JenkinsRule.java:565)
	at org.junit.internal.runners.statements.FailOnTimeout$CallableStatement.call(FailOnTimeout.java:298)
	at org.junit.internal.runners.statements.FailOnTimeout$CallableStatement.call(FailOnTimeout.java:292)
	at java.base/java.util.concurrent.FutureTask.run(FutureTask.java:264)
	at java.base/java.lang.Thread.run(Thread.java:834)
Caused by: java.lang.StringIndexOutOfBoundsException: offset 0, count -1, length 5
	at java.base/java.lang.String.checkBoundsOffCount(String.java:3304)
	at java.base/java.lang.String.<init>(String.java:465)
	at hudson.TcpSlaveAgentListener$PingAgentProtocol.connect(TcpSlaveAgentListener.java:416)
	at hudson.TcpSlaveAgentListener.shutdown(TcpSlaveAgentListener.java:196)
	at jenkins.model.Jenkins._cleanUpShutdownTcpSlaveAgent(Jenkins.java:3548)
	at jenkins.model.Jenkins.cleanUp(Jenkins.java:3294)
	... 6 more

Co-Authored-By: NWadeck Follonier <wadeck.follonier@gmail.com>

Clarifying relation between host/port variables as used by Remoting-based CLI vs. other protocol clients.

* [JENKINS-38711] Add UncaughtExceptionHandler to remoting related threads

* [JENKINS-38711] Restart listener thread if it fails

* [JENKINS-38711] Reschedule the thread on a delay

* [JENKINS-38711] Allow the listener to actually be restarted

* [JENKINS-38711] Minor updates based on feedback

* [JENKINS-38711] Check to see if port has changed

* [JENKINS-38711] Check for updates inside of rescheduler too

* [JENKINS-38711] Remove port checks outside of the rescheduler

* [JENKINS-38711] Add empty constructor to fix CI build

* [JENKINS-38711] Remove unused port variable

This reverts commit 50bec3f6.

* [JENKINS-38711] Add UncaughtExceptionHandler to remoting related threads

* [JENKINS-38711] Restart listener thread if it fails

* [JENKINS-38711] Reschedule the thread on a delay

* [JENKINS-38711] Allow the listener to actually be restarted

* [JENKINS-38711] Minor updates based on feedback

(cherry picked from commit b5fe89cc)

Make functional tests a little quieter so we can focus on test output rather than boilerplate logging.

* Clean up usages of IOUtils.closeQuietly and related calls predating Java 7.

* Review comments from @oleg-nenashev.

* Noticed another place where try-with-resources would protect against a potential leak.

[FIXED JENKINS-38473] Set a short timeout on the socket when using it to wake the acceptor thread. (#2564)

* [FIXED JENKINS-38473] Set a short timeout on the socket when using it to wake the acceptor thread.

* [JENKINS-38473] Remove leftover typing in wrong window

(cherry picked from commit 1689f6b7)

[FIXED JENKINS-38473] Set a short timeout on the socket when using it to wake the acceptor thread. (#2564)

* [FIXED JENKINS-38473] Set a short timeout on the socket when using it to wake the acceptor thread.

* [JENKINS-38473] Remove leftover typing in wrong window

report the server's address, too

Added a simple diagnostic HTTP response to the TcpSlaveAgentListener.