ERROR: Communications link failure

Bom dia, estou tentando executar o projeto da aula mas aparece o seguinte erro . Alguém pode me ajudar? ERRO:

mai 29, 2019 9:38:21 PM org.hibernate.jpa.internal.util.LogHelper logPersistenceUnitInformation
INFO: HHH000204: Processing PersistenceUnitInfo [name: financas]
mai 29, 2019 9:38:21 PM org.hibernate.Version logVersion
INFO: HHH000412: Hibernate Core {5.4.2.Final}
mai 29, 2019 9:38:21 PM org.hibernate.annotations.common.reflection.java.JavaReflectionManager <clinit>
INFO: HCANN000001: Hibernate Commons Annotations {5.1.0.Final}
mai 29, 2019 9:38:21 PM org.hibernate.engine.jdbc.connections.internal.DriverManagerConnectionProviderImpl configure
WARN: HHH10001002: Using Hibernate built-in connection pool (not for production use!)
Loading class `com.mysql.jdbc.Driver'. This is deprecated. The new driver class is `com.mysql.cj.jdbc.Driver'. The driver is automatically registered via the SPI and manual loading of the driver class is generally unnecessary.
mai 29, 2019 9:38:21 PM org.hibernate.engine.jdbc.connections.internal.DriverManagerConnectionProviderImpl buildCreator
INFO: HHH10001005: using driver [com.mysql.jdbc.Driver] at URL [jdbc:mysql://hostname/financas?useTimezone=true&serverTimezone=UTC]
mai 29, 2019 9:38:21 PM org.hibernate.engine.jdbc.connections.internal.DriverManagerConnectionProviderImpl buildCreator
INFO: HHH10001001: Connection properties: {user=root, password=****}
mai 29, 2019 9:38:21 PM org.hibernate.engine.jdbc.connections.internal.DriverManagerConnectionProviderImpl buildCreator
INFO: HHH10001003: Autocommit mode: false
mai 29, 2019 9:38:21 PM org.hibernate.engine.jdbc.connections.internal.DriverManagerConnectionProviderImpl$PooledConnections <init>
INFO: HHH000115: Hibernate connection pool size: 20 (min=1)
mai 29, 2019 9:38:24 PM org.hibernate.engine.jdbc.env.internal.JdbcEnvironmentInitiator initiateService
WARN: HHH000342: Could not obtain connection to query metadata : null
mai 29, 2019 9:38:24 PM org.hibernate.dialect.Dialect <init>
INFO: HHH000400: Using dialect: org.hibernate.dialect.MySQL5InnoDBDialect
mai 29, 2019 9:38:24 PM org.hibernate.engine.jdbc.spi.SqlExceptionHelper logExceptions
WARN: SQL Error: 0, SQLState: 08S01
mai 29, 2019 9:38:24 PM org.hibernate.engine.jdbc.spi.SqlExceptionHelper logExceptions

ERROR: 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.
Exception in thread "main" org.hibernate.service.spi.ServiceException: Unable to create requested service [org.hibernate.engine.jdbc.env.spi.JdbcEnvironment]...

Segue abaixo meu código.

<persistence xmlns="http://java.sun.com/xml/ns/persistence"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://java.sun.com/xml/ns/persistence
        http://java.sun.com/xml/ns/persistence/persistence_2_0.xsd"
    version="2.0">

    <!-- unidade de persistencia com o nome financas -->
    <persistence-unit name="financas">

        <!-- Implementacao do JPA, no nosso caso Hibernate -->
        <provider>org.hibernate.jpa.HibernatePersistenceProvider</provider>

        <!-- Aqui sao listadas todas as entidades -->
        <class>br.com.caelum.financas.modelo.Conta</class>

        <properties>    
            <!-- Propriedades JDBC -->
            <property name="javax.persistence.jdbc.driver" 
                value="com.mysql.jdbc.Driver" />

            <property name="javax.persistence.jdbc.url" 

                value="jdbc:mysql://hostname/databaseName?useTimezone=true&amp;serverTimezone=UTC" />

            <property name="javax.persistence.jdbc.user" value="root" />
            <property name="javax.persistence.jdbc.password" value="000000" />

            <!-- Configuracoes especificas do Hibernate -->
            <property name="hibernate.dialect" 
                value="org.hibernate.dialect.MySQL5InnoDBDialect" />

            <property name="hibernate.hbm2ddl.auto" value="update" />
            <property name="hibernate.show_sql" value="true" />
            <property name="hibernate.format_sql" value="true" />
        </properties>
    </persistence-unit>
</persistence>

Tentei trocar "jdbc:mysql://hostname/databaseName?useTimezone=true&serverTimezone=UTC"por "jdbc:mysql://hostname/financas?useTimezone=true&serverTimezone=UTC" mas o erro persistia