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Cannot find mysql.sock file and cannot check if mysql is running on mac using xampp

I am extremely new to Computer Science, and we were asked by our professor to connect our java file to our MySQL database using XAMPP. My java file would not connect to the database I created on phpmyadmin no matter what I did, so I tried to get to the root of the problem by entering mysqladmin -u root -p ping on my terminal. This was the result:
error: 'Can't connect to local MySQL server through socket '/tmp/mysql.sock' (2)'
Check that mysqld is running and that the socket: '/tmp/mysql.sock' exists!
I went to my tmp folder and could not find the mysql.sock file. I tried checking if mysql was running by entering ps aux | grep mysql on my terminal. The result was
username 5078 0.0 0.0 4277504 672 s001 S+ 11:21AM 0:00.00 grep mysql
but I have no idea what that means. I also tried commands like service mysql restart and sudo service mysqld start, but terminal would say
zsh: command not found: service
I tried locating for the mysql.sock file because I thought it was just misplaced, so I entered locate mysql.sock and netstat -ln | grep mysql on the terminal, but they returned nothing. I also tried mysqladmin -p -u <user-name> variables but the result again was
mysqladmin: connect to server at 'localhost' failed
error: 'Can't connect to local MySQL server through socket '/tmp/mysql.sock' (2)'
Check that mysqld is running and that the socket: '/tmp/mysql.sock' exists!
The weird thing is that on the Log tab of XAMPP, it says INFO: Successfully started "mysql". I am also able to connect to my databases using my php projects, but I just can't connect with my java files. Please help, I am desperate.

Unable to create directory path [/User/Desktop/db2/logs] for Neo4j store

I am trying to use a tool that, in two steps, analyzes code smells for android.
In the first step, the tool parses an apk and generates within a directory .db files that should then be converted to CSV files in the next step; however, whenever I try to run the second step, the console returns the following error:
java.io.IOException: Unable to create directory path [/User/Desktop/db2/logs] for Neo4j store.
I think it is a Neo4J configuration problem.
I am currently running the tool with the following Java configuration:
echo $JAVA_HOME
/home/User/openlogic-openjdk-11.0.15
update-alternatives --config java
* 0 /usr/lib/jvm/java-11-openjdk-amd64/bin/java 1111 auto mode
To be safe, I also started Neo4J, which returned the following output
sudo systemctl status neo4j.service
neo4j.service - Neo4j Graph Database
Loaded: loaded (/lib/systemd/system/neo4j.service; enabled; vendor preset: enabled)
Active: active (running) since Wed 2022-07-06 20:11:04 CEST; 16min ago
Main PID: 1040 (java)
Tasks: 57 (limit: 18901)
Memory: 705.4M
CPU: 16.639s
CGroup: /system.slice/neo4j.service
└─1040 /usr/bin/java -cp "/var/lib/neo4j/plugins:/etc/neo4j:/usr/share/neo4j/lib/*:/var/lib/neo4j/plugins/*" -XX:+UseG1GC -XX:-OmitStackTraceInFastThrow -XX:+AlwaysPreTouch -XX:+UnlockExper>.
How can I solve this?

You posted this error:
java.io.IOException: Unable to create directory path [/User/Desktop/db2/logs] for Neo4j store.
From that error, it looks like:
Neo4j was installed at "/User/Desktop/db2"
The permissions for that directory do not have "write" permission
I tried to reproduce this locally using Neo4j Community 4.4.5, following the steps below.
I do see an IOException related to "logs", but it's slightly different from what you posted. Perhaps we're on different versions of Neo4j.
Open terminal into install directory: cd neo4j
Verify "neo4j" is stopped: ./bin/neo4j stop
Rename existing "logs" directory: mv logs logs.save
Remove write permission for the Neo4j install: chmod u-w .
Start neo4j in console mode: ./bin/neo4j console
Observe errors in console output
2022-07-08 03:28:38.081+0000 INFO Starting...
ERROR StatusLogger Unable to create file [****************************]/neo4j/logs/debug.log
java.io.IOException: Could not create directory [****************************]/neo4j/logs
...
To fix things, try:
Get a terminal into your Neo4j directory:
cd /User/Desktop/db2
Set write permissions for the entire directory tree:
chmod u+w -R .
Start neo4j in console mode:
./bin/neo4j console
If this works and you're able to run neo4j fine, it points to an issue with user permissions when running neo4j as a system service.
The best steps from there depend on the system, your access, how comfortable you are making changes, probably other things. An easy, brute-force hammer would be to manually create each directory you discover (such as "/User/Desktop/db2/logs") and grant premissions to all users (chmod ugo+w .), then try re-running the service, see what errors pop up. Repeat that until you're able to run the service without errors.

How to ensure HSQLDB properties configuration loaded on Windows?

I have a problem with HSQLDB V2.3 on Windows. I can't connect with new databases using the HSQLDB Server.
Is there a log or debug option for the server so I can check the properties loaded and file paths, etc?
Is my properties file OK? I wasn't sure how to formulate file paths for windows.
Can I use quotes on file path names?
Is the connection string I'm using for the tmp db correct?
What's the correct syntax to use the --props server argument?
--props path
--props path/filename
I have set-up two environment variables (too keep it simple*). These variables don't have any effect except to save my typing. Initially I was loading the server from the HSQLDB folder directly.
HSQLDB_HOME ... home folder for the current HSQLDB
HSQLDB_DATA ... folder for data repository
I am following the the steps from:
Running and Using HSQLDB
Every time I connect via the server it makes a database called, "test" instead of letting me connect to either of the two databases specified in the server.properties.
%HSQLDB_DATA%/
test.log
test.properties
test.script
test.tmp/ .......... (folder)
test.lck
I made a 'server.properties' file in:
%HSQLDB_HOME%/lib/
where the HSQLDB JAR file is. I want two databases: tmp and dev:
# -- tmp
server.database.0=file:hsqldb/tmp_db/tmp
server.dbname.0=tmp_db
#
####
#
# -- dev
server.database.1=file:r:/.data/hsqldb/dev_db/dev
server.dbname.1=dev_db
I expected that the properties file to be enough to set-up two databases. When I run the hsqldb manager I don't get a connection for tmp say:
"jdbc:hsqldb:hsql://localhost/tmp"
user: SA, password: ""
I get a pop-up error:
database alias does not exist (Manager)
[Thread[HSQLDB Connection #26827674,5,HSQLDB Connections #372f7a8d]]: database alias=tmp does not exist (Server)
I created these two manually using the cmd-line, e.g. named "tmp":
%JAVA_HOME%\bin\java.exe -classpath %HSQLDB_HOME%\lib\hsqldb.jar org.hsqldb.server.Server org.hsqldb.server.Server --database.1 file:r:/.data/hsqldb/tmp_db --dbname.1 tmp_db
And could connect and create tmp:
%HSQLDB_DATA%/tmp_db/
tmp.log
tmp.properties
tmp.script
tmp.tmp/ .......... (folder)
tmp.lck
as forecast in the documentation. When I start-up the HSQLDB Server with the aforesaid 'server.properties' file or specifying properties explicitly:
%JAVA_HOME%\bin\java.exe -classpath %HSQLDB_HOME%\lib\hsqldb.jar org.hsqldb.server.Server --trace true --props %HSQLDB_DATA%
The server will only let me connect with a database called "test" as described at the beginning of the question.
Because the properties file looks good and the in-process file connection string works,
jdbc:hsqldb:hsqldb/tmp_db/tmp
I am left considering that the server.properties file is in the wrong place or not loading for some reason. It would be wonderful if there's a way for the server to dump the properties file at start-time :-) Thanks in advance for your suggestions ...

I have found the problem. Firstly, thanks to this tutorial:
HSQLDB Installation
After reviewing this I realised my error.
The server.properties file must be in the current folder when the server script runs. I had read that on the Running and Using HSQLDB manual page but misinterpreted its meaning and I put the properties file in my %HSQLDB_HOME%/lib folder. Oops.
When you look at the BAT script, it actually changed the current folder to be the %HSQLDB_HOME%/data folder ...
cd ..\data
So the default location for your server.properties file should be your: %HSQLDB_HOME%/data if you want to work with the default runServer.bat script.
For those wanting to separate data from the server software. I made an improvement for the default script using the two environment variables as follows.
HSQLDB_HOME ... home folder for the current HSQLDB
HSQLDB_DATA ... folder for data repository
runServer.bat:
#cd /d %HSQLDB_DATA%
#cd
#echo.
#rem __ #pause
%JAVA_HOME%\bin\java -classpath %HSQLDB_HOME%\lib\hsqldb.jar org.hsqldb.server.Server %1 %2 %3 %4 %5 %6 %7 %8 %9
#echo.
#pause
Which now expects my server.properties file in the %HSQL_DATA% folder. And that works. Also for my server since it is for development /testing, I'm using the --trace=true option. Like a lot of these things, now I get-it, it all makes perfect sense. Hopefully my misunderstanding will assist others who haven't found a simple tutorial before resorting to stackoverflow.

Deploying java application using capistrano

I am trying to get my java application deployed on tomcat server (in windows), I am getting the following error. Please help me with some guideline on the following connection error. I have admin privilege and server is running in local.
C:\builds>cap local deploy
DL is deprecated, please use Fiddle
* 2013-04-01 14:19:06 executing `local'
* 2013-04-01 14:19:06 executing `deploy'
* 2013-04-01 14:19:06 executing `deploy:update'
** transaction: start
* 2013-04-01 14:19:06 executing `deploy:update_code'
* executing "xcopy C:/_Savita/app/my-app \"C:/builds/releases/20
130401084906\" /S/I/Y/Q/E && (echo > C:/builds/releases/20130401084906/REVISION
)"
servers: ["localhost"]
*** [deploy:update_code] rolling back
* executing "rm -rf C:/builds/releases/20130401084906; true"
servers: ["localhost"]
** [deploy:update_code] exception while rolling back: Capistrano::ConnectionErr
or, connection failed for: localhost (Errno::ECONNREFUSED: No connection could b
e made because the target machine actively refused it. - connect(2))
connection failed for: localhost (Errno::ECONNREFUSED: No connection could be ma
de because the target machine actively refused it. - connect(2))
Please find below the deploy script used
set :application, "myApp"
#set :scm, "git"
set :repository, "C:/_Savita/app/my-app"
#set :branch, "master"
default_run_options[:pty] = true
ssh_options[:forward_agent] = true
task :local do
roles.clear
server "localhost", :app
set :user, "Savita Doddamani"
set :java_home, "C:/Program Files (x86)/Java/jdk1.6.0_25"
set :tomcat_home, "C:/Program Files (x86)/Apache Software Foundation/Tomcat 6.0"
set :tomcat_manager, "user"
set :tomcat_manager_password, "pwd"
set :maven_home, "C:/_Savita/softwares/apache-maven-2.2.1"
set :deploy_to, "C:/builds/"
set :use_sudo, false
namespace :tomcat do
task :deploy do
puts "==================Building with Maven======================" #Line 22
run "export JAVA_HOME=#{java_home} && cd #{deploy_to}/ && #{maven_home}/bin/mvn clean install package -DskipTests"
puts "==================Undeploy war======================"#Line 24
run "curl --user #{tomcat_manager}:#{tomcat_manager_password} http://$CAPISTRANO:HOST$:8080/manager/text/undeploy?path=/#{application}"
puts "==================Deploy war to Tomcat======================" #Line 26
run "curl --upload-file #{deploy_to}/current/target/dist/local/#{application}*.war --user #{tomcat_manager}:#{tomcat_manager_password} http://$CAPISTRANO:HOST$:8080/manager/text/deploy?path=/#{application}"
end
end
after "deploy", "tomcat:deploy" #Line 30
after "tomcat:deploy", "deploy:cleanup" # keep only the last 5 releases
end

ECONNREFUSED is the return from the connect(2) system call. It means that the server process is not listening on TCP port 8080. Java takes time to start up and you may be attempting to connect via curl too soon or you have not configured Tomcat to listen on port 8080 or you have not started Tomcat at all.

HSQLDB alias doesnt exist, linux sh script

The problem is that when my hsql server starts, it tells that the alias exists, everything connected successfully:
rpi#RaspberryPi:/home/snb/update_skynetwork/apps/App/bin$ sh skysql.sh
/home/snb/update_skynetwork/apps/App/lib/hsqldb-2.2.8.jar
[Server#133796]: [Thread[main,5,main]]: checkRunning(false) entered
[Server#133796]: [Thread[main,5,main]]: checkRunning(false) exited
[Server#133796]: Startup sequence initiated from main() method
[Server#133796]: Could not load properties from file
[Server#133796]: Using cli/default properties only
[Server#133796]: Initiating startup sequence...
[Server#133796]: Server socket opened successfully in 7 ms.
] opened sucessfully in 1462 ms.=0, id=0, db=file:/home/snb/update_skynetwork/apps/App/sky-network-hsqldb/sky-network-hsqldb, alias=sky-network-hsqldb
[Server#133796]: Startup sequence completed in 1473 ms.
[Server#133796]: 2012-12-20 10:23:11.843 HSQLDB server 2.2.8 is online on port 9001
[Server#133796]: To close normally, connect and execute SHUTDOWN SQL
[Server#133796]: From command line, use [Ctrl]+[C] to abort abruptly
But when I try to connect with my java app I receive this error:
-on server:
[Server#133796]: [Thread[HSQLDB Connection #bdb503,5,HSQLDB Connections #133796]]: database alias=sky-network-hsqldb does not exist
[Server#133796]: [Thread[HSQLDB Connection #110003,5,HSQLDB Connections #133796]]: database alias=sky-network-hsqldb does not exist
[Server#133796]: [Thread[HSQLDB Connection #175d6ab,5,HSQLDB Connections #133796]]: database alias=sky-network-hsqldb does not exist
-on client:
Caused by: org.hsqldb.HsqlException: General error: database alias does not exist
at org.hsqldb.error.Error.error(Unknown Source)
at org.hsqldb.ClientConnection.<init>(Unknown Source)
... 16 more
I have tried to test the connection with the sqltool, but still the same.
Also, I have checked the alias name in the properties of client - all the same, like needed. The jars of hsql are the same. Everything matches.
As OS I have a Raspberry-pi VM.
EDIT
This is my sqltool.sh :
#! /bin/sh -e
export CLASSPATH=../lib/hsqldb-2.2.8.jar:$CLASSPATH
export CLASSPATH=../lib/sqltool.jar:$CLASSPATH
java -classpath $CLASSPATH org.hsqldb.cmdline.SqlTool -- inlineRc=url=jdbc:hsqldb:hsql://localhost/sky-network-hsqldb,user=SA,password=

It seems the only possible issue is shell script.
Can you use a simple name for the alias, without hyphens.
The database file name should be OK with the hyphens.
The server message states you do not have a server.properties file. In this case, the database file path and the name/alias should be on the command line. Please check your shell script and report / change the line that starts the server.