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java.lang.NoClassDefFoundError when deploying to Glassfish application server

I have created a simple demo rest service which queries Ethereum to get basic information. I am using the Web3j library version 5.0.0 https://mvnrepository.com/artifact/org.web3j/core/5.0.0
I have added the library to the project using Maven. Built the project which compiles successfully and trying to debug it. I am using GlassFish 6.2.51 for my application server.
Any ideas why I am getting the below error?
[2023-02-09 11:44:19,706] Artifact demoapi:war exploded: java.io.IOException: com.sun.enterprise.admin.remote.RemoteFailureException: Error occurred during deployment: Exception while loading the app : java.lang.IllegalStateException: ContainerBase.addChild: start: org.apache.catalina.LifecycleException: org.apache.catalina.LifecycleException: java.lang.NoClassDefFoundError: org/web3j/protocol/Web3jService.

java.lang.NoClassDefFoundError: java/util/Base64$Encoder on Centos 7

Summary
We have spring boot projects that working on Tomcat in Centos 7. I'm using kafka for message transactions. When tomcat started, #KafkaListener 's trying to get metadata. At that time I'm getting exception;
java.lang.NoClassDefFoundError: java/util/Base64$Encoder
What I've Tried
At the first place i thought this was all about old kafka-logs. I removed them and restarted the server. Everything was fine. But today i got this exception again. Removing kafka-logs didn't solve my issue.
Kafka Broker Version: kafka_2.13-2.8.0
Kafka Client Version: org.apache.kafka:kafka-clients:jar:2.8.0
OpenJDK: 1.8.0_292
SLF4J: Failed toString() invocation on an object of type
[org.apache.kafka.common.requests.MetadataRequest] Reported exception:
java.lang.NoClassDefFoundError: java/util/Base64$Encoder
at org.apache.kafka.common.Uuid.toString(Uuid.java:101)
at org.apache.kafka.common.message.MetadataRequestData$MetadataRequestTopic.toString(MetadataRequestData.java:662)
at org.apache.kafka.common.protocol.MessageUtil.deepToString(MessageUtil.java:53)
at org.apache.kafka.common.message.MetadataRequestData.toString(MetadataRequestData.java:373)
at org.apache.kafka.common.requests.AbstractRequest.toString(AbstractRequest.java:115)
at org.apache.kafka.common.requests.AbstractRequest.toString(AbstractRequest.java:120)
at org.slf4j.helpers.MessageFormatter.safeObjectAppend(MessageFormatter.java:277)
at org.slf4j.helpers.MessageFormatter.deeplyAppendParameter(MessageFormatter.java:249)
at org.slf4j.helpers.MessageFormatter.arrayFormat(MessageFormatter.java:211)
at org.slf4j.helpers.MessageFormatter.arrayFormat(MessageFormatter.java:161)
at org.apache.kafka.common.utils.LogContext$LocationAwareKafkaLogger.writeLog(LogContext.java:428)
at org.apache.kafka.common.utils.LogContext$LocationAwareKafkaLogger.debug(LogContext.java:229)
at org.apache.kafka.clients.NetworkClient.doSend(NetworkClient.java:522)
at org.apache.kafka.clients.NetworkClient.doSend(NetworkClient.java:501)
at org.apache.kafka.clients.NetworkClient.sendInternalMetadataRequest(NetworkClient.java:467)
at org.apache.kafka.clients.NetworkClient$DefaultMetadataUpdater.maybeUpdate(NetworkClient.java:1141)
at org.apache.kafka.clients.NetworkClient$DefaultMetadataUpdater.maybeUpdate(NetworkClient.java:1046)
at org.apache.kafka.clients.NetworkClient.poll(NetworkClient.java:559)
at org.apache.kafka.clients.consumer.internals.ConsumerNetworkClient.poll(ConsumerNetworkClient.java:265)
at org.apache.kafka.clients.consumer.internals.ConsumerNetworkClient.poll(ConsumerNetworkClient.java:236)
at org.apache.kafka.clients.consumer.KafkaConsumer.pollForFetches(KafkaConsumer.java:1296)
at org.apache.kafka.clients.consumer.KafkaConsumer.poll(KafkaConsumer.java:1237)
at org.apache.kafka.clients.consumer.KafkaConsumer.poll(KafkaConsumer.java:1210)
at org.springframework.kafka.listener.KafkaMessageListenerContainer$ListenerConsumer.doPoll(KafkaMessageListenerContainer.java:1206)
at org.springframework.kafka.listener.KafkaMessageListenerContainer$ListenerConsumer.pollAndInvoke(KafkaMessageListenerContainer.java:1110)
at org.springframework.kafka.listener.KafkaMessageListenerContainer$ListenerConsumer.run(KafkaMessageListenerContainer.java:1031)
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
at java.util.concurrent.FutureTask.run(FutureTask.java:266)
at java.lang.Thread.run(Thread.java:748)

java.net.UnknownHostException in WildFly start

I'm getting the following error when I start up a Java server process (WildFly application server):
Caused by: java.net.UnknownHostException: proxy01.phx2.fedoraproject.org: Name or service not known
at java.net.Inet4AddressImpl.lookupAllHostAddr(Native Method)
at java.net.InetAddress$2.lookupAllHostAddr(InetAddress.java:929)
at java.net.InetAddress.getAddressesFromNameService(InetAddress.java:1324)
at java.net.InetAddress.getLocalHost(InetAddress.java:1501)
The server is not harmed by this error, but it bothers me to have this error in the logs. It is something related with my environment. Indeed, the problem happens no matter which version of the server and on any location of my file system.
I have checked in /etc/hosts and /etc/resolv.conf but I really don't have idea where the "proxy01.phx2.fedoraproject.org" comes from.
Any idea?
Thanks

Getting runtime error while trying to connect mysql from java

java.lang.ClassNotFoundException: com.mysql.jdbc.Driver from [Module "deployment.Sample.war:main" from Service Module Loader].
The above one is my error message.
I have included mysql-connector-java-5.1.35-bin.jar in my class path and it is shown in the libraries as well.
I am using JBoss AS 7.1.0.Final server to run it. How to resolve this error?

java.io.IOException - Java

I am getting repeatedly below error while running java application on IBM - WebSphere Application Server.
[ 00000024 TCP E org.jgroups.protocols.TP$IncomingPacket run failed handling incoming message
java.io.IOException: failed reading header
at org.jgroups.Message.readHeader(Message.java:757)
at org.jgroups.Message.readFrom(Message.java:643)
at org.jgroups.protocols.TP.readMessage(TP.java:1502)
at org.jgroups.protocols.TP.access$700(TP.java:49)
at org.jgroups.protocols.TP$IncomingPacket.run(TP.java:1804)
at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:906)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:929)
at java.lang.Thread.run(Thread.java:773)
Caused by: java.io.EOFException
at java.io.DataInputStream.readShort(DataInputStream.java:309)
at org.jgroups.Message.readHeader(Message.java:734)
... 7 more
java.io.IOException: failed reading header
at org.jgroups.Message.readHeader(Message.java:757)
at org.jgroups.Message.readFrom(Message.java:643)
at org.jgroups.protocols.TP.readMessage(TP.java:1502)
at org.jgroups.protocols.TP.access$700(TP.java:49)
at org.jgroups.protocols.TP$IncomingPacket.run(TP.java:1804)
at java.util.concurrent.ThreadPoolExecutor$CallerRunsPolicy.rejectedExecution(ThreadPoolExecutor.java:1763)
at org.jgroups.util.ShutdownRejectedExecutionHandler.rejectedExecution(ShutdownRejectedExecutionHandler.java:39)
at java.util.concurrent.ThreadPoolExecutor.reject(ThreadPoolExecutor.java:779)
at java.util.concurrent.ThreadPoolExecutor.execute(ThreadPoolExecutor.java:667)
at org.jgroups.protocols.TP.dispatchToThreadPool(TP.java:1354)
at org.jgroups.protocols.TP.receive(TP.java:1321)
at org.jgroups.protocols.BasicTCP.receive(BasicTCP.java:258)
at org.jgroups.blocks.BasicConnectionTable.receive(BasicConnectionTable.java:239)
at org.jgroups.blocks.BasicConnectionTable$Connection.run(BasicConnectionTable.java:664)
at java.lang.Thread.run(Thread.java:773)
Caused by: java.io.EOFException
at java.io.DataInputStream.readShort(DataInputStream.java:309)
at org.jgroups.Message.readHeader(Message.java:734)
... 14 more
Application has file export operation. Somehow files are deleted from specified location and whenever I try to run application through above exception continuously. I tried killing java but that too do not help.
Please suggest how to resolve.

Stop IBM Webservice application already started services from services.msc :)