Jdbc error after update java 8 - mysql

Question

I have a server linux Ubuntu (14.04.4) with Tomcat and Java in it.
I recently upgraded Java from 7 to 8 (leaving Tomcat 7)
this is the situation
my web application starts but throws an exception during the db connection
Jul 11, 2016 3:41:19 PM org.apache.tomcat.jdbc.pool.ConnectionPool init
SEVERE: Unable to create initial connections of pool.
java.sql.SQLException: com.mysql.jdbc.Driver
at org.apache.tomcat.jdbc.pool.PooledConnection.connectUsingDriver(PooledConnection.java:254)
at org.apache.tomcat.jdbc.pool.PooledConnection.connect(PooledConnection.java:182)
at org.apache.tomcat.jdbc.pool.ConnectionPool.createConnection(ConnectionPool.java:701)
at org.apache.tomcat.jdbc.pool.ConnectionPool.borrowConnection(ConnectionPool.java:635)
at org.apache.tomcat.jdbc.pool.ConnectionPool.init(ConnectionPool.java:486)
at org.apache.tomcat.jdbc.pool.ConnectionPool.<init>(ConnectionPool.java:144)
at org.apache.tomcat.jdbc.pool.DataSourceProxy.pCreatePool(DataSourceProxy.java:116)
at org.apache.tomcat.jdbc.pool.DataSourceProxy.createPool(DataSourceProxy.java:103)
at org.apache.tomcat.jdbc.pool.DataSourceProxy.getConnection(DataSourceProxy.java:127)
this is the connection URL: jdbc:mysql://localhost:3306/
NOTE 1: mysql-connector-java-5.0.8-bin.jar is in tomcat lib
NOTE 2: I tried to put mysql-connector-java-5.0.8-bin.jar even in WEB-INF/lib
NOTE 3: the same application with the same configuration of Tomcat and Java works fine in my local pc.
UPDATE:
here the configuration:
PoolProperties p = new PoolProperties();
p.setRemoveAbandoned(Boolean.parseBoolean(System.getProperties().getProperty(pathContestoString+"db.removeAbandoned")));
p.setRemoveAbandonedTimeout(Integer.parseInt(System.getProperties().getProperty(pathContestoString+"db.removeAbandonedTimeout")));
p.setLogAbandoned(Boolean.parseBoolean(System.getProperties().getProperty(pathContestoString+"db.logAbandoned")));
p.setMaxActive(Integer.parseInt(System.getProperties().getProperty(pathContestoString+"db.maxActive")));
p.setMaxIdle(Integer.parseInt(System.getProperties().getProperty(pathContestoString+"db.maxIdle")));
p.setMaxWait(Integer.parseInt(System.getProperties().getProperty(pathContestoString+"db.maxWait")));
p.setUsername(System.getProperties().getProperty(pathContestoString+"db.user"));
p.setPassword(System.getProperties().getProperty(pathContestoString+"db.pwd"));
p.setDriverClassName("com.mysql.jdbc.Driver");
p.setUrl(System.getProperties().getProperty(pathContestoString+"db.url")+System.getProperties().getProperty(pathContestoString+"db.dbname")+"?useEncoding=true&characterEncoding=UTF-8&ssl=true");
// factory?
// closeMethod?
p.setValidationQuery("SELECT 1");
p.setTestOnBorrow(true);
App.properties:
db.user=myUser
db.pwd=myPwd
db.url=jdbc:mysql://localhost:3306/
db.dbname=myDbName
db.maxActive=50
db.maxIdle=30
db.maxWait=50000
db.removeAbandoned=true
db.removeAbandonedTimeout=20
db.logAbandoned=true