src/main/java/com/github/ddth/cql/SessionManager.java
public Session getSession(String hostsAndPorts, String username, String password,
            String keyspace) {
        return getSession(hostsAndPorts, username, password, keyspace, false);
    }
public Session getSession(String hostsAndPorts, String username, String password,
            String keyspace) {
        return getSession(hostsAndPorts, username, password, keyspace, false);
    }
Obtain a Cassandra session instance.

<p>
The existing session instance will be returned if such existed.
</p>

@param hostsAndPorts
@param username
@param password
@param keyspace
@return
@throws NoHostAvailableException
@throws AuthenticationException