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Issue with openjdk:17 docker image

I'm using the openjdk:17 docker image, the os is Oracle Linux Server v8.5. I ssh into the container with root user and found almost all common commands are not available. I have tried ps, pidof etc but getting command not found error. I'm trying to add a preStop hook to kill the java process gracefully but need a command to find the java process. Any idea how to achieve this?
Here is the output of ls -l /proc/*/exe. There sees to be a number of pid associated to the java process, but I'm sure I only have one. What is the clear way to find the pid and kill it? one liner is preferred
lrwxrwxrwx 1 root root 0 Mar 3 16:45 /proc/1/exe -> /usr/java/openjdk-17/bin/java
lrwxrwxrwx 1 root root 0 Mar 3 20:35 /proc/106/exe -> /usr/bin/bash
lrwxrwxrwx 1 root root 0 Mar 3 20:45 /proc/164/exe -> /usr/java/openjdk-17/bin/jshell
lrwxrwxrwx 1 root root 0 Mar 3 20:45 /proc/185/exe -> /usr/java/openjdk-17/bin/java
lrwxrwxrwx 1 root root 0 Mar 3 21:15 /proc/self/exe -> /usr/bin/coreutils
lrwxrwxrwx 1 root root 0 Mar 3 21:15 /proc/thread-self/exe -> /usr/bin/coreutils

zookeeper Starting error :'JAVA_HOME error in zookeeper.out'

When I do
bin/zkServer.sh start #It shows it has started
ZooKeeper JMX enabled by default
Using config: /data/sparkHA/zookeeper-3.4.9/bin/../conf/zoo.cfg
Starting zookeeper ... STARTED
Afetr few second when i check status, I got
ZooKeeper JMX enabled by default
Using config: /data/sparkHA/zookeeper-3.4.9/bin/../conf/zoo.cfg
Error contacting service. It is probably not running.
My zookeeper.out says
nohup: failed to run command â/usr/bin/java/bin/javaâ: Not a directory
But my JAVA_HOME in bashrc is usr/bin/java, How come one extra /bin/java is added , that results in an invalid directory.
Also echo $JAVA_HOME outputs
/usr/bin/java
How to approach this error. Please Help. Thanks.
Also tried setting JAVA_HOME in zkServer.sh also by following Zookeeper not starting, nohup error but getting same error.

Your JAVA_HOME point to /usr/bin/java file but it should point to root directory of your JDK. For example for me this is:
➜ ~ echo $JAVA_HOME
/Library/Java/JavaVirtualMachines/jdk1.8.0_112.jdk/Contents/Home
➜ ~ ll $JAVA_HOME
total 52064
-rw-rw-r-- 1 root wheel 3.2K Oct 1 09:00 COPYRIGHT
-rw-rw-r-- 1 root wheel 40B Oct 1 09:01 LICENSE
-rw-rw-r-- 1 root wheel 159B Oct 1 09:01 README.html
-rwxrwxr-x 1 root wheel 108K Sep 22 22:49 THIRDPARTYLICENSEREADME-JAVAFX.txt
-rw-rw-r-- 1 root wheel 173K Oct 1 09:01 THIRDPARTYLICENSEREADME.txt
drwxrwxr-x 46 root wheel 1.5K Oct 1 09:04 bin
drwxrwxr-x 9 root wheel 306B Oct 1 09:00 db
drwxrwxr-x 9 root wheel 306B Oct 1 09:00 include
-rwxrwxr-x 1 root wheel 4.9M Sep 22 22:49 javafx-src.zip
drwxrwxr-x 10 root wheel 340B Oct 1 09:02 jre
drwxrwxr-x 14 root wheel 476B Oct 1 09:02 lib
drwxrwxr-x 5 root wheel 170B Oct 1 09:01 man
-rw-rw-r-- 1 root wheel 529B Oct 1 09:01 release
-rw-rw-r-- 1 root wheel 20M Oct 1 09:01 src.zip
So, try to set valid path to JDK root directory. I think it should fix your problem.

Fixed Rest Endpoints

I have a war file deployed on tomcat ( /var/lib/tomcat7/webapps folder ), say, rest-api-webapp-0.0.1.war
To access the rest endpoint check, exposed in this war, I use curl in the format
curl -X POST -H "Content-Type:application/x-www-form-urlencoded" -d "remarks=Tester" https://localhost:8080/rest-api-webapp-0.0.1/check The problem I face is, whenever I up the patch/major/minor versions of my webapp, I need to change the curl appropriately (say the version is now 0.1.4, then the curl must change as curl -X POST -H "Content-Type:application/x-www-form-urlencoded" -d "remarks=Tester" https://localhost:8080/rest-api-webapp-0.1.4/check. I donot wish to change the way the client calls the endpoint (because it requires the client to upgrade their app, which they resent and see as high maintenance) Can this be avoided by doing something like this
Create a symbolic link as below ln -s rest-api-webapp-0.0.1.war rest-api inside the /var/log/tomcat7/webapps folder so that whennever I up the version, I just change the symlink to point to the new version and the client need not do anything to use the new version of the api. In effect, I need the api endpoint to be fixed and not change as and when I up the versions on the server. For Ex: I need the endpoint to be fixed as https:gva.atr.in/colouring-api/check and whenever I have a major change in the controllers and all that I need to do is just update the symlink and not change the endpoint. If you find that this approach is flawed, please show me the right direction as I have been trying to read about this from the past 2 days, but found very less articles that address my problem.

I read the tomcat documentation and realised that I need to create a symbolic link to the war file and give the symbolic file the war extension. So If this is what you have in your tomcat webapps directory
/var/lib/tomcat7/webapps user1$ ls
drwxr-xr-x 11 user1 wheel 374 Oct 19 21:52 .
drwxr-xr-x 9 user1 admin 306 Oct 19 19:36 ..
drwxr-xr-x 19 user1 wheel 646 Aug 29 20:19 ROOT
drwxr-xr-x 55 user1 wheel 1870 Aug 29 20:19 docs
drwxr-xr-x 4 user1 wheel 136 Oct 19 19:46 rest-api-webapp-0.2.1
-rw-r--r-- 1 user1 wheel 48258097 Oct 19 19:46 rest-api-webapp-0.2.1.war
drwxr-xr-x 7 user1 wheel 238 Aug 29 20:19 host-manager
drwxr-xr-x 8 user1 wheel 272 Aug 29 20:19 manager
Do this,
ln -s rest-api-webapp-0.2.1.war rest-api.war So that the directory looks like this (Wait for sometime for the tomcat engine to deploy the new war)
drwxr-xr-x 11 user1 wheel 374 Oct 19 21:52 .
drwxr-xr-x 9 user1 admin 306 Oct 19 19:36 ..
drwxr-xr-x 19 user1 wheel 646 Aug 29 20:19 ROOT
drwxr-xr-x 4 user1 wheel 136 Oct 19 21:52 rest-api
drwxr-xr-x 4 user1 wheel 136 Oct 19 19:46 rest-api-webapp-0.2.1
-rw-r--r-- 1 user1 wheel 48258097 Oct 19 19:46 rest-api-webapp-0.2.1.war
lrwxr-xr-x 1 user1 wheel 25 Oct 19 21:51 rest-api.war -> rest-api-webapp-0.2.1.war
drwxr-xr-x 7 user1 wheel 238 Aug 29 20:19 host-manager
drwxr-xr-x 8 user1 wheel 272 Aug 29 20:19 manager If needed restart your tomcat and you can use the curl command like this curl -X POST -H "Content-Type:application/x-www-form-urlencoded" -d "remarks=Tester" https://localhost:8080/rest-api/check totally not bothering about the major, minor, patch versions. All that you need to do once you have a new version is unlink rest-apiln -s rest-api-webapp-X.Y.Z.war rest-api.war

JConsole location in Linux

I am trying to run jconsole from my machine but I can't find the location of the .sh . I have tried finding it in different directories and setting JAVA_HOME to the jdk.
$which java
/usr/bin/java
$java -version
java version "1.7.0_51"
OpenJDK Runtime Environment (rhel-2.4.4.1.el6_5-x86_64 u51-b02)
OpenJDK 64-Bit Server VM (build 24.45-b08, mixed mode)
$whereis java
java: /usr/bin/java /etc/java /usr/lib/java /usr/share/java /usr/share/man/man1/java.1.gz
I looked in /usr/lib/jvm and I found
drwxr-xr-x. 3 root root 4096 Apr 23 2013 java-1.5.0-gcj-1.5.0.0
drwxr-xr-x. 3 root root 4096 Jan 27 2014 java-1.6.0-openjdk-1.6.0.0.x86_64
drwxr-xr-x. 3 root root 4096 Feb 5 2014 java-1.7.0-openjdk-1.7.0.51.x86_64
lrwxrwxrwx. 1 root root 21 Feb 5 2014 jre -> /etc/alternatives/jre
lrwxrwxrwx. 1 root root 27 Apr 23 2013 jre-1.5.0 -> /etc/alternatives/jre_1.5.0
lrwxrwxrwx. 1 root root 26 Apr 23 2013 jre-1.5.0-gcj -> java-1.5.0-gcj-1.5.0.0/jre
lrwxrwxrwx. 1 root root 27 Feb 5 2014 jre-1.6.0 -> /etc/alternatives/jre_1.6.0
lrwxrwxrwx. 1 root root 37 Feb 5 2014 jre-1.6.0-openjdk.x86_64 -> java-1.6.0-openjdk- 1.6.0.0.x86_64/jre
lrwxrwxrwx. 1 root root 27 Feb 5 2014 jre-1.7.0 -> /etc/alternatives/jre_1.7.0
lrwxrwxrwx. 1 root root 38 Feb 5 2014 jre-1.7.0-openjdk.x86_64 -> java-1.7.0-openjdk-1.7.0.51.x86_64/jre
lrwxrwxrwx. 1 root root 25 Apr 23 2013 jre-gcj -> /etc/alternatives/jre_gcj
lrwxrwxrwx. 1 root root 29 Feb 5 2014 jre-openjdk -> /etc/alternatives/jre_openjdk
and in java-1.7.0-openjdk-1.7.0.51.x86_64/jre/bin/, I only found
[root#portal01 bin]# ll
total 200
-rwxr-xr-x. 1 root root 9536 Jan 14 2014 java
-rwxr-xr-x. 1 root root 9656 Jan 14 2014 keytool
-rwxr-xr-x. 1 root root 9856 Jan 14 2014 orbd
-rwxr-xr-x. 1 root root 9688 Jan 14 2014 pack200
-rwxr-xr-x. 1 root root 10984 Jan 14 2014 policytool
-rwxr-xr-x. 1 root root 9648 Jan 14 2014 rmid
-rwxr-xr-x. 1 root root 9656 Jan 14 2014 rmiregistry
-rwxr-xr-x. 1 root root 9688 Jan 14 2014 servertool
-rwxr-xr-x. 1 root root 9896 Jan 14 2014 tnameserv
-rwxr-xr-x. 1 root root 92264 Jan 14 2014 unpack200
..even though there are 200 files. How can I find and run jconsole?

jconsole is part of the Java SDK, it appears you only have the JRE installed.

You can run jconsole directly from your terminal by running the command jconsole.
reena#IM-1500:~$ jconsole
It will launch java monitoring console dialog.

From https://serverfault.com/questions/179908/fedora-jconsole-location:
Try running: yum provides */jconsole
that will tell you what package you need as well as where it's located in the package.

Once you set the path of JDK in Linux then this command execute easily might be you had not included the JAVA_HOME with PATH variable.
plz follow this discussion

If you have Java JDK installed in your Linux machine, usually jconsole is located at /usr/bin/ as a symbolic link.
Example from my Linux VM running Centos6
$ which jconsole
/usr/bin/jconsole
$ ls -l /usr/bin/jconsole
lrwxrwxrwx. 1 root root 26 Sep 4 10:05 /usr/bin/jconsole -> /etc/alternatives/jconsole
$ ls -l /etc/alternatives/jconsole
lrwxrwxrwx. 1 root root 51 Sep 4 10:05 /etc/alternatives/jconsole -> /usr/lib/jvm/java-1.7.0-openjdk.x86_64/bin/jconsole
But you mentioned you got the a command not found error when you typed jconsole at the prompt. Can you find if jconsole is available in one of the jdk's bin directory?
$ ls -l /usr/lib/jvm/java-1.7.0-openjdk.x86_64/bin | grep jconsole
If yes, then add this in your PATH environment variable like so
$ export PATH=$PATH:/usr/lib/jvm/java-1.7.0-openjdk.x86_64/bin
or put this in your ~/.bashrc if you are using Bash.
If jconsole is not there, then maybe you need to try another jdk which you have installed or re-install the jdk.

Please install JDK Development Package to get Jconsole

Find all available JREs on Mac OS X from Java application installer

If Java application requires certain JRE version then how can I check its availability on Mac OS X during installation?

It should be as simple as looking at /System/Library/Frameworks/JavaVM.framework/Versions/
E.g. from my machine:
manoa:~ stu$ ll /System/Library/Frameworks/JavaVM.framework/Versions/
total 56
774077 lrwxr-xr-x 1 root wheel 5 Jul 23 15:31 1.3 -> 1.3.1
167151 drwxr-xr-x 3 root wheel 102 Jan 14 2008 1.3.1
167793 lrwxr-xr-x 1 root wheel 5 Feb 21 2008 1.4 -> 1.4.2
774079 lrwxr-xr-x 1 root wheel 3 Jul 23 15:31 1.4.1 -> 1.4
166913 drwxr-xr-x 8 root wheel 272 Feb 21 2008 1.4.2
168494 lrwxr-xr-x 1 root wheel 5 Feb 21 2008 1.5 -> 1.5.0
166930 drwxr-xr-x 8 root wheel 272 Feb 21 2008 1.5.0
774585 lrwxr-xr-x 1 root wheel 5 Jul 23 15:31 1.6 -> 1.6.0
747415 drwxr-xr-x 8 root wheel 272 Jul 23 10:24 1.6.0
167155 drwxr-xr-x 8 root wheel 272 Jul 23 15:31 A
776765 lrwxr-xr-x 1 root wheel 1 Jul 23 15:31 Current -> A
774125 lrwxr-xr-x 1 root wheel 3 Jul 23 15:31 CurrentJDK -> 1.5
manoa:~ stu$

This artical may help:
http://developer.apple.com/technotes/tn2002/tn2110.html
Summery:
String javaVersion = System.getProperty("java.version");
if (javaVersion.startsWith("1.4")) {
// New features for 1.4
}