A conexão do Tomcat / Hibernate ao MySql falha com "Falha no link de comunicação" e "Permissão negada"

Estou tentando conectar ao MySql (= MariaDB) no host local (vamos chamá-lo de A) de um aplicativo da web tomcat usando o Hibernate, mas continuo recebendo falha no link de comunicação (o rastreamento completo de exceção anexado abaixo).

Eu tenho outra réplica do banco de dados em uma máquina diferente (vamos chamá-lo de B) e também usando um terceiro computador para desenvolvimento (vamos chamá-lo de C).

1) Não tenho problemas ao conectar de C a um dos bancos de dados (A e B). 2) Em "A", não tenho problemas para conectar localmente ao banco de dados (executando o comando 'mysql -u'). Também não tenho problemas ao fazer o telnet na porta 3306 para A ou B., portanto, presumo que os dois DBs estejam em funcionamento e disponíveis e disponíveis para conexões.

O único problema é quando estou tentando conectar-me do tomcat de produção (executando em A) ao A ou B db. Eu recebo o erro:

com.mysql.cj.jdbc.exceptions.CommunicationsException: Communications link failure

The last packet sent successfully to the server was 0 milliseconds ago. The driver has not received any packets from the server.

Em casos semelhantes desse erro, vi que a maioria dos erros ocorreu devido a credenciais de usuário / senha inválidas ou IPs ilegais. Também tentei alterar o ip para localhost, 127.0.0.1 e 10.90.41.155 (que é o ip real da máquina). Nada ajuda e também lembre-se de que a conexão falha apenas na instalação específica do tomcat no A.

Eu também tentei o seguinte: 1) Adicionado "-Djava.net.preferIPv4Stack = true" à inicialização do catalina 2) Tentei conectar-me a endereços / portas ilegais - isso mudou (como esperado) o erro final de "permissão negada" para "não rota para hospedar ". 3) Adicionado o seguinte à minha cadeia de conexão: "autoReconnect = true & useUnicode = true & createDatabaseIfNotExist = true & characterEncoding = utf-8" - isso resultou no mesmo erro ("Tentativa de reconexão 3 vezes. Desistindo.") "Permissão negada (falha na conexão)" 4) Tentei os dois URLs do banco de dados. para o banco de dados local tentado com localhost, 127.0.0.1 e o IP real. tentou com e sem ": 3306" na cadeia de conexão

Anexado está o arquivo hibernate.cfg + rastreamento completo do servidor da exceção:

<?xml version="1.0" encoding="utf-8"?>
<!DOCTYPE hibernate-configuration SYSTEM 
"http://www.hibernate.org/dtd/hibernate-configuration-3.0.dtd">

<hibernate-configuration>
   <session-factory>
   <property name="hibernate.dialect">
      org.hibernate.dialect.MySQLDialect
   </property>
   <property name="hibernate.connection.driver_class">
      com.mysql.jdbc.Driver
   </property>

   <!-- Assume test is the database name -->
   <property name="hibernate.connection.url">
      jdbc:mysql://10.90.41.151/boonder
   </property>
   <property name="hibernate.connection.username">
      root
   </property>
   <property name="hibernate.connection.password">
   XXXXXXXXXX
   </property>

   <!-- List of XML mapping files      -->
   <mapping resource="User.hbm.xml"/>
   <mapping resource="Issue.hbm.xml"/>
   <mapping resource="TraderIssue.hbm.xml"/>

</session-factory>
</hibernate-configuration>

A exceção é:

        type Exception report

        message Handler dispatch failed; nested exception is java.lang.ExceptionInInitializerError

        description The server encountered an internal error that prevented it from fulfilling this request.

        exception

        org.springframework.web.util.NestedServletException: Handler dispatch failed; nested exception is java.lang.ExceptionInInitializerError
            org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:982)
            org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:901)
            org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:970)
            org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:872)
            javax.servlet.http.HttpServlet.service(HttpServlet.java:650)
            org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:846)
            javax.servlet.http.HttpServlet.service(HttpServlet.java:731)
            com.aldondy.boonder.web.controllers.CharacterEncodingFilter.doFilter(CharacterEncodingFilter.java:27)
            org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
        root cause

        java.lang.ExceptionInInitializerError
            com.aldondy.boonder.bl.DataSingleton.<init>(DataSingleton.java:54)
            com.aldondy.boonder.bl.DataSingleton.instance(DataSingleton.java:74)
            com.aldondy.boonder.web.controllers.LoginCtrl.loginInner(LoginCtrl.java:62)
            com.aldondy.boonder.web.controllers.LoginCtrl.login(LoginCtrl.java:41)
            sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
            sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
            sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
            java.lang.reflect.Method.invoke(Method.java:498)
            org.springframework.web.bind.annotation.support.HandlerMethodInvoker.invokeHandlerMethod(HandlerMethodInvoker.java:180)
            org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter.invokeHandlerMethod(AnnotationMethodHandlerAdapter.java:440)
            org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter.handle(AnnotationMethodHandlerAdapter.java:428)
            org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:967)
            org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:901)
            org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:970)
            org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:872)
            javax.servlet.http.HttpServlet.service(HttpServlet.java:650)
            org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:846)
            javax.servlet.http.HttpServlet.service(HttpServlet.java:731)
            com.aldondy.boonder.web.controllers.CharacterEncodingFilter.doFilter(CharacterEncodingFilter.java:27)
            org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
        root cause

        org.hibernate.service.spi.ServiceException: Unable to create requested service [org.hibernate.engine.jdbc.env.spi.JdbcEnvironment]
            org.hibernate.service.internal.AbstractServiceRegistryImpl.createService(AbstractServiceRegistryImpl.java:271)
            org.hibernate.service.internal.AbstractServiceRegistryImpl.initializeService(AbstractServiceRegistryImpl.java:233)
            org.hibernate.service.internal.AbstractServiceRegistryImpl.getService(AbstractServiceRegistryImpl.java:210)
            org.hibernate.engine.jdbc.internal.JdbcServicesImpl.configure(JdbcServicesImpl.java:51)
            org.hibernate.boot.registry.internal.StandardServiceRegistryImpl.configureService(StandardServiceRegistryImpl.java:94)
            org.hibernate.service.internal.AbstractServiceRegistryImpl.initializeService(AbstractServiceRegistryImpl.java:242)
            org.hibernate.service.internal.AbstractServiceRegistryImpl.getService(AbstractServiceRegistryImpl.java:210)
            org.hibernate.boot.model.process.spi.MetadataBuildingProcess.handleTypes(MetadataBuildingProcess.java:352)
            org.hibernate.boot.model.process.spi.MetadataBuildingProcess.complete(MetadataBuildingProcess.java:111)
            org.hibernate.boot.model.process.spi.MetadataBuildingProcess.build(MetadataBuildingProcess.java:83)
            org.hibernate.boot.internal.MetadataBuilderImpl.build(MetadataBuilderImpl.java:418)
            org.hibernate.boot.internal.MetadataBuilderImpl.build(MetadataBuilderImpl.java:87)
            org.hibernate.cfg.Configuration.buildSessionFactory(Configuration.java:691)
            org.hibernate.cfg.Configuration.buildSessionFactory(Configuration.java:726)
            com.aldondy.boonder.bl.DataSingleton.<init>(DataSingleton.java:48)
            com.aldondy.boonder.bl.DataSingleton.instance(DataSingleton.java:74)
            com.aldondy.boonder.web.controllers.LoginCtrl.loginInner(LoginCtrl.java:62)
            com.aldondy.boonder.web.controllers.LoginCtrl.login(LoginCtrl.java:41)
            sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
            sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
            sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
            java.lang.reflect.Method.invoke(Method.java:498)
            org.springframework.web.bind.annotation.support.HandlerMethodInvoker.invokeHandlerMethod(HandlerMethodInvoker.java:180)
            org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter.invokeHandlerMethod(AnnotationMethodHandlerAdapter.java:440)
            org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter.handle(AnnotationMethodHandlerAdapter.java:428)
            org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:967)
            org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:901)
            org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:970)
            org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:872)
            javax.servlet.http.HttpServlet.service(HttpServlet.java:650)
            org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:846)
            javax.servlet.http.HttpServlet.service(HttpServlet.java:731)
            com.aldondy.boonder.web.controllers.CharacterEncodingFilter.doFilter(CharacterEncodingFilter.java:27)
            org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
        root cause

        org.hibernate.exception.JDBCConnectionException: Error calling Driver#connect
            org.hibernate.exception.internal.SQLStateConversionDelegate.convert(SQLStateConversionDelegate.java:115)
            org.hibernate.engine.jdbc.connections.internal.BasicConnectionCreatorEu tenho outra réplica do banco de dados em uma máquina diferente (vamos chamá-lo de B) e também usando um terceiro computador para desenvolvimento (vamos chamá-lo de C).1.convert(BasicConnectionCreator.java:101)
            org.hibernate.engine.jdbc.connections.internal.BasicConnectionCreator.convertSqlException(BasicConnectionCreator.java:123)
            org.hibernate.engine.jdbc.connections.internal.DriverConnectionCreator.makeConnection(DriverConnectionCreator.java:41)
            org.hibernate.engine.jdbc.connections.internal.BasicConnectionCreator.createConnection(BasicConnectionCreator.java:58)
            org.hibernate.engine.jdbc.connections.internal.PooledConnections.addConnections(PooledConnections.java:123)
            org.hibernate.engine.jdbc.connections.internal.PooledConnections.<init>(PooledConnections.java:42)
            org.hibernate.engine.jdbc.connections.internal.PooledConnections.<init>(PooledConnections.java:20)
            org.hibernate.engine.jdbc.connections.internal.PooledConnections$Builder.build(PooledConnections.java:161)
    ...
            org.hibernate.cfg.Configuration.buildSessionFactory(Configuration.java:691)
            org.hibernate.cfg.Configuration.buildSessionFactory(Configuration.java:726)
            com.aldondy.boonder.bl.DataSingleton.<init>(DataSingleton.java:48)
            com.aldondy.boonder.bl.DataSingleton.instance(DataSingleton.java:74)
            com.aldondy.boonder.web.controllers.LoginCtrl.loginInner(LoginCtrl.java:62)
            com.aldondy.boonder.web.controllers.LoginCtrl.login(LoginCtrl.java:41)
            sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
            sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
            sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
            java.lang.reflect.Method.invoke(Method.java:498)
            org.springframework.web.bind.annotation.support.HandlerMethodInvoker.invokeHandlerMethod(HandlerMethodInvoker.java:180)
            org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter.invokeHandlerMethod(AnnotationMethodHandlerAdapter.java:440)
            org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter.handle(AnnotationMethodHandlerAdapter.java:428)
            org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:967)
            org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:901)
            org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:970)
            org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:872)
            javax.servlet.http.HttpServlet.service(HttpServlet.java:650)
            org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:846)
            javax.servlet.http.HttpServlet.service(HttpServlet.java:731)
            com.aldondy.boonder.web.controllers.CharacterEncodingFilter.doFilter(CharacterEncodingFilter.java:27)
            org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
        root cause

        com.mysql.cj.jdbc.exceptions.CommunicationsException: Communications link failure

        The last packet sent successfully to the server was 0 milliseconds ago. The driver has not received any packets from the server.
            com.mysql.cj.jdbc.exceptions.SQLError.createCommunicationsException(SQLError.java:166)
            com.mysql.cj.jdbc.exceptions.SQLExceptionsMapping.translateException(SQLExceptionsMapping.java:58)
            com.mysql.cj.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:853)
            com.mysql.cj.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:440)
            com.mysql.cj.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:241)
            com.mysql.cj.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:221)
            org.hibernate.engine.jdbc.connections.internal.DriverConnectionCreator.makeConnection(DriverConnectionCreator.java:38)
            org.hibernate.engine.jdbc.connections.internal.BasicConnectionCreator.createConnection(BasicConnectionCreator.java:58)

    ...

    org.hibernate.service.internal.AbstractServiceRegistryImpl.getService(AbstractServiceRegistryImpl.java:210)
            org.hibernate.boot.model.process.spi.MetadataBuildingProcess.handleTypes(MetadataBuildingProcess.java:352)
            org.hibernate.boot.model.process.spi.MetadataBuildingProcess.complete(MetadataBuildingProcess.java:111)
            org.hibernate.boot.model.process.spi.MetadataBuildingProcess.build(MetadataBuildingProcess.java:83)
            org.hibernate.boot.internal.MetadataBuilderImpl.build(MetadataBuilderImpl.java:418)
            org.hibernate.boot.internal.MetadataBuilderImpl.build(MetadataBuilderImpl.java:87)
            org.hibernate.cfg.Configuration.buildSessionFactory(Configuration.java:691)
            org.hibernate.cfg.Configuration.buildSessionFactory(Configuration.java:726)
            com.aldondy.boonder.bl.DataSingleton.<init>(DataSingleton.java:48)
            com.aldondy.boonder.bl.DataSingleton.instance(DataSingleton.java:74)
            com.aldondy.boonder.web.controllers.LoginCtrl.loginInner(LoginCtrl.java:62)
            com.aldondy.boonder.web.controllers.LoginCtrl.login(LoginCtrl.java:41)
            sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
            sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
            sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
            java.lang.reflect.Method.invoke(Method.java:498)
            org.springframework.web.bind.annotation.support.HandlerMethodInvoker.invokeHandlerMethod(HandlerMethodInvoker.java:180)
            org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter.invokeHandlerMethod(AnnotationMethodHandlerAdapter.java:440)
            org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter.handle(AnnotationMethodHandlerAdapter.java:428)
            org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:967)
            org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:901)
            org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:970)
            org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:872)
            javax.servlet.http.HttpServlet.service(HttpServlet.java:650)
            org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:846)
            javax.servlet.http.HttpServlet.service(HttpServlet.java:731)
            com.aldondy.boonder.web.controllers.CharacterEncodingFilter.doFilter(CharacterEncodingFilter.java:27)
            org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
        root cause

        com.mysql.cj.core.exceptions.CJCommunicationsException: Communications link failure

        The last packet sent successfully to the server was 0 milliseconds ago. The driver has not received any packets from the server.
            sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
            sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62)
            sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
            java.lang.reflect.Constructor.newInstance(Constructor.java:423)
            com.mysql.cj.core.exceptions.ExceptionFactory.createException(ExceptionFactory.java:54)
            com.mysql.cj.core.exceptions.ExceptionFactory.createException(ExceptionFactory.java:93)
            com.mysql.cj.core.exceptions.ExceptionFactory.createException(ExceptionFactory.java:133)
            com.mysql.cj.core.exceptions.ExceptionFactory.createCommunicationsException(ExceptionFactory.java:149)
            com.mysql.cj.mysqla.io.MysqlaSocketConnection.connect(MysqlaSocketConnection.java:83)
            com.mysql.cj.mysqla.MysqlaSession.connect(MysqlaSession.java:204)
            com.mysql.cj.jdbc.ConnectionImpl.connectOneTryOnly(ConnectionImpl.java:975)
            com.mysql.cj.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:843)
            com.mysql.cj.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:440)
            com.mysql.cj.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:241)
            com.mysql.cj.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:221)
            org.hibernate.engine.jdbc.connections.internal.DriverConnectionCreator.makeConnection(DriverConnectionCreator.java:38)
            org.hibernate.engine.jdbc.connections.internal.BasicConnectionCreator.createConnection(BasicConnectionCreator.java:58)
            org.hibernate.engine.jdbc.connections.internal.PooledConnections.addConnections(PooledConnections.java:123)
            org.hibernate.engine.jdbc.connections.internal.PooledConnections.<init>(PooledConnections.java:42)
            org.hibernate.engine.jdbc.connections.internal.PooledConnections.<init>(PooledConnections.java:20)
            org.hibernate.engine.jdbc.connections.internal.PooledConnections$Builder.build(PooledConnections.java:161)
            org.hibernate.engine.jdbc.connections.internal.DriverManagerConnectionProviderImpl.buildPool(DriverManagerConnectionProviderImpl.java:109)
            org.hibernate.engine.jdbc.connections.internal.DriverManagerConnectionProviderImpl.configure(DriverManagerConnectionProviderImpl.java:72)
            org.hibernate.boot.registry.internal.StandardServiceRegistryImpl.configureService(StandardServiceRegistryImpl.java:94)
            org.hibernate.service.internal.AbstractServiceRegistryImpl.initializeService(AbstractServiceRegistryImpl.java:242)
     org.hibernate.engine.jdbc.internal.JdbcServicesImpl.configure(JdbcServicesImpl.java:51)
            org.hibernate.boot.registry.internal.StandardServiceRegistryImpl.configureService(StandardServiceRegistryImpl.java:94)
            org.hibernate.service.internal.AbstractServiceRegistryImpl.initializeService(AbstractServiceRegistryImpl.java:242)
            org.hibernate.service.internal.AbstractServiceRegistryImpl.getService(AbstractServiceRegistryImpl.java:210)
            org.hibernate.boot.model.process.spi.MetadataBuildingProcess.handleTypes(MetadataBuildingProcess.java:352)
            org.hibernate.boot.model.process.spi.MetadataBuildingProcess.complete(MetadataBuildingProcess.java:111)
            org.hibernate.boot.model.process.spi.MetadataBuildingProcess.build(MetadataBuildingProcess.java:83)
            org.hibernate.boot.internal.MetadataBuilderImpl.build(MetadataBuilderImpl.java:418)
            org.hibernate.boot.internal.MetadataBuilderImpl.build(MetadataBuilderImpl.java:87)
            org.hibernate.cfg.Configuration.buildSessionFactory(Configuration.java:691)
            org.hibernate.cfg.Configuration.buildSessionFactory(Configuration.java:726)
            com.aldondy.boonder.bl.DataSingleton.<init>(DataSingleton.java:48)
            com.aldondy.boonder.bl.DataSingleton.instance(DataSingleton.java:74)
            com.aldondy.boonder.web.controllers.LoginCtrl.loginInner(LoginCtrl.java:62)
            com.aldondy.boonder.web.controllers.LoginCtrl.login(LoginCtrl.java:41)
            sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
            sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
            sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
            java.lang.reflect.Method.invoke(Method.java:498)
            org.springframework.web.bind.annotation.support.HandlerMethodInvoker.invokeHandlerMethod(HandlerMethodInvoker.java:180)
            org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter.invokeHandlerMethod(AnnotationMethodHandlerAdapter.java:440)
            org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter.handle(AnnotationMethodHandlerAdapter.java:428)
            org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:967)
            org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:901)
            org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:970)
            org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:872)
            javax.servlet.http.HttpServlet.service(HttpServlet.java:650)
            org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:846)
            javax.servlet.http.HttpServlet.service(HttpServlet.java:731)
            com.aldondy.boonder.web.controllers.CharacterEncodingFilter.doFilter(CharacterEncodingFilter.java:27)
            org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
        root cause

        java.net.SocketException: Permission denied (connect failed)
            java.net.PlainSocketImpl.socketConnect(Native Method)
            java.net.AbstractPlainSocketImpl.doConnect(AbstractPlainSocketImpl.java:350)
            java.net.AbstractPlainSocketImpl.connectToAddress(AbstractPlainSocketImpl.java:206)
            java.net.AbstractPlainSocketImpl.connect(AbstractPlainSocketImpl.java:188)
            java.net.SocksSocketImpl.connect(SocksSocketImpl.java:392)
            java.net.Socket.connect(Socket.java:589)
            com.mysql.cj.core.io.StandardSocketFactory.connect(StandardSocketFactory.java:202)
            com.mysql.cj.mysqla.io.MysqlaSocketConnection.connect(MysqlaSocketConnection.java:57)
            com.mysql.cj.mysqla.MysqlaSession.connect(MysqlaSession.java:204)
            com.mysql.cj.jdbc.ConnectionImpl.connectOneTryOnly(ConnectionImpl.java:975)
            com.mysql.cj.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:843)
            com.mysql.cj.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:440)
            com.mysql.cj.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:241)
            com.mysql.cj.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:221)
            org.hibernate.engine.jdbc.connections.internal.DriverConnectionCreator.makeConnection(DriverConnectionCreator.java:38)
            org.hibernate.engine.jdbc.connections.internal.BasicConnectionCreator.createConnection(BasicConnectionCreator.java:58)
            org.hibernate.engine.jdbc.connections.internal.PooledConnections.addConnections(PooledConnections.java:123)
            org.hibernate.engine.jdbc.connections.internal.PooledConnections.<init>(PooledConnections.java:42)
            org.hibernate.engine.jdbc.connections.internal.PooledConnections.<init>(PooledConnections.java:20)
            org.hibernate.engine.jdbc.connections.internal.PooledConnections$Builder.build(PooledConnections.java:161)
            org.hibernate.engine.jdbc.connections.internal.DriverManagerConnectionProviderImpl.buildPool(DriverManagerConnectionProviderImpl.java:109)
            org.hibernate.engine.jdbc.connections.internal.DriverManagerConnectionProviderImpl.configure(DriverManagerConnectionProviderImpl.java:72)
            org.hibernate.boot.registry.internal.StandardServiceRegistryImpl.configureService(StandardServiceRegistryImpl.java:94)
            org.hibernate.service.internal.AbstractServiceRegistryImpl.initializeService(AbstractServiceRegistryImpl.java:242)
            org.hibernate.service.internal.AbstractServiceRegistryImpl.getService(AbstractServiceRegistryImpl.java:210)
            org.hibernate.engine.jdbc.env.internal.JdbcEnvironmentInitiator.buildJdbcConnectionAccess(JdbcEnvironmentInitiator.java:145)
            org.hibernate.engine.jdbc.env.internal.JdbcEnvironmentInitiator.initiateService(JdbcEnvironmentInitiator.java:66)
            org.hibernate.engine.jdbc.env.internal.JdbcEnvironmentInitiator.initiateService(JdbcEnvironmentInitiator.java:35)
            org.hibernate.boot.registry.internal.StandardServiceRegistryImpl.initiateService(StandardServiceRegistryImpl.java:88)
            org.hibernate.service.internal.AbstractServiceRegistryImpl.createService(AbstractServiceRegistryImpl.java:259)
            org.hibernate.service.internal.AbstractServiceRegistryImpl.initializeService(AbstractServiceRegistryImpl.java:233)
            org.hibernate.service.internal.AbstractServiceRegistryImpl.getService(AbstractServiceRegistryImpl.java:210)

...
    org.hibernate.boot.internal.MetadataBuilderImpl.build(MetadataBuilderImpl.java:87)
            org.hibernate.cfg.Configuration.buildSessionFactory(Configuration.java:691)
            org.hibernate.cfg.Configuration.buildSessionFactory(Configuration.java:726)
            com.aldondy.boonder.bl.DataSingleton.<init>(DataSingleton.java:48)
            com.aldondy.boonder.bl.DataSingleton.instance(DataSingleton.java:74)
            com.aldondy.boonder.web.controllers.LoginCtrl.loginInner(LoginCtrl.java:62)
            com.aldondy.boonder.web.controllers.LoginCtrl.login(LoginCtrl.java:41)
            sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
            sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
            sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
            java.lang.reflect.Method.invoke(Method.java:498)
            org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter.handle(AnnotationMethodHandlerAdapter.java:428)
            org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:967)
            org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:901)
            org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:970)
            org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:872)
            javax.servlet.http.HttpServlet.service(HttpServlet.java:650)
            org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:846)
            javax.servlet.http.HttpServlet.service(HttpServlet.java:731)
            com.aldondy.boonder.web.controllers.CharacterEncodingFilter.doFilter(CharacterEncodingFilter.java:27)
            org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
        note The full stack trace of the root cause is available in the Apache Tomcat/7.0.76 logs.

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