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Yet another MySQL connection issue

I have to deploy my java server app to a Debian 8 server. It tries to connect to the MySQL server via unix domain socket or tcp (depending on connection string). It works fine on my Debian 9 development server, but gives (as i think) useless error messages on the live server. I have root access to both servers but not allowed to do much on the live server. As i had version troubles compiling java on D9 and running it on D8, i have installed openjdk-7-jdk and mysql java connector on the D8 from the Debian repo, copied (symlinked) the connector jar to the lib directory of the source, and recompiled the app. Now it starts but when trying to connect to the database, it throws the following errors:
TCP: Connection refused
UDS: File not found (nonexistent file or device) ((the translation may not be correct, sorry))
Both connections (TCP and UDS) works fine from PHP & PDO.
Connection strings:
TCP: jdbc:mysql://localhost/<dbname>?user=<user>&password=<pwd>&useJDBCCompliantTimezoneShift=true&useLegacyDatetimeCode=false&serverTimezone=UTC&characterEncoding=utf8
UDS: jdbc:mysql:///<dbname>?socketFactory=com.mysql.jdbc.NamedPipeSocketFactory&namedPipePath=/var/run/mysqld/mysqld.sock&user=<user>&password=<pwd>&useJDBCCompliantTimezoneShift=true&useLegacyDatetimeCode=false&serverTimezone=UTC&characterEncoding=utf8
dbname, user, pwd and the socket file path are copied and pasted from the working PHP code. Worth noting that i'm not a java expert, i may not know something that should be known using these older libraries. Some source code:
Class.forName("java.sql.Driver");
...
Connection db = DriverManager.getConnection(Settings.sqlConnection.value);
try(Statement stmt = c.createStatement())
{
stmt.execute("SET #now = UTC_TIMESTAMP()");
}
...
Version info:
Debian 8.7
MySQL server 5.5.53-0+deb8u1
java version "1.7.0_181"
OpenJDK Runtime Environment (IcedTea 2.6.14) (7u181-2.6.14-1~deb8u1)
OpenJDK 64-Bit Server VM (build 24.181-b01, mixed mode)
mysql-connector-java-5.1.42.jar
What am i missing? Why do i get connection refused and missing file error messages while clearly the server is listening and the socket file is there and have the right permissions - and other clients can connect?

Nevermind, i've got the solution (not much after posting the question and so much after started having the issue... as usual).
UDS: I simply mixed up named pipes with unix domain sockets which are two entirely different implementations of the same concept. JDBC simply can't do UDS. Now i realize that i tested my code on the dev server probably with TCP connection only.
TCP: The server socket was bound to the server's exact address therefore localhost wouldn't work. My narrow thinking about connection refused error completely misguided me.

WSO2 error HTTP Status 500

I have a problem on my EMM virtual machine.
When I go to my console an error appears, as the screen shows
I think I have done all the previous tasks correctly, but only the people who do not work are not mistaken, so the error can come from the previous steps.
I'm running Windows Server 2008 64-bit
I have Java JDK 8 update 121
I have the latest version of WSO2 EMM
I'm logged in admin

This is due to the SSL certificate available in wso2carbon.jks in set to localhost not to the ip address. You can simply navigate to the emm server by clicking on the WSO2 logo.
and you can create a self singed SSL certificate to the ip address and replace the current cert in order to prevent this screen.

Timeout while deploying Java Application to remote glassfish server from Netbeans

while deploying to a remote Glassfish 4.1 Server from Netbeans 8.0.1, i get a Timeout.
I configured the Glassfish Server by adding a new Server Instance and that seemed to work. I can see the applications running on the server and i am able to undeploy a application (directly from netbeans).
But when i try to deploy my application to the remote Server, i get a timeout Exception.
(i used enable-secure-admin to gain remote access from netbeans to the server)
What confuses me is, that when i enabled secure admin, i expected to see a https:// url in netbeans. But this url starts with http:// and i cant find an option to change this.
Server Attributes:
Host: [remote-ip]
DAS Port: 4848
Domain: domain1 (same as on the remote server)
Target: empty
Username PW : as set on the remote server
"Enable JDBC Driver Deployment" and "Preserve Sessions Across Redeployment" are checked

Could you please attach the logs.
most probably its issue with the grizzly jar.
Please try the patched grizzly jar and see if it works for you.
Checkout : https://java.net/jira/browse/GRIZZLY-1713 for the same

How to find weblogic t3 adminurl

I have a weblogic folder, From this - How can i find the adminurl that I can use with the below command
java weblogic.Deployer –adminurl t3://server:7001 –username system –password weblogic –listapps
I tried looking into setupinfo.txt, portlist.ini - but somehow this did not help/work. How can get this working?
I get errors/exceptions like these (after few attempts)
The loading of the trusted certificate list raised a certificate parsing exception PKIX: Unsupported OID in the AlgorithmIdentifier object
Unable to connect to 'http://server:7001': Destination unreachable; java.net.ConnectException: Tried all: 1 addresses, but could not connect over HTTPS to server: localhost port: 7102; No available router to destination
based on setupinfo.txt, I am able to login to the web console - but I need to know how to get this command working with adminurl !!!
Thanks,

Got it, thanks Alex.
Steps
Find startscript.xml under your weblogic domain , search this file for "ADMIN_URL"
The same can be done by web console UI ..... Admin Console Login to AdminConsole->Server->Configuration->ListenPort (enable and note down the port)
Bingo.

How do I connect to Derby which is included with WebLogic?

I'm trying to add the Derby included with WebLogic as a data source. I'm running WebLogic 10.3.5. I didn't see a Derby flag in the setDomainEnv.cmd, so I added the client driver to the CLASSPATH:
set CLASSPATH=%PRE_CLASSPATH%;%WEBLOGIC_CLASSPATH%;%POST_CLASSPATH%;%WLP_POST_CLASSPATH%;%WL_HOME%\common\derby\lib\derbyclient.jar
in setDomainEnv.cmd. Now when I try to activate my data source in WebLogic I get:
An error occurred during activation of changes, please see the log for
details. Message icon - Error weblogic.application.ModuleException:
Message icon - Error java.net.ConnectException : Error connecting to
server localhost on port 1527 with message Connection refused:
connect.
What else do I need to do to get this to work?

I believe your local derby is not up yet. To check this, issue:
netstat -an | findstr 1527.
See if it returns anything. If nothing is returned, try to start the Derby Network Service manually. Go to <WLS_HOME>\common\derby\bin and click the startNetworkServer.cmd.
Double check with netstat again. If it's there, you can try to add to the datasource.
Note: this only covers manually start the Derby network service (not automatially start it upon weblogic start, which a bit tricky).

Either whatever is supposed to be running on that port isn't running or there is a firewall issue.