Hi metero,
I presume you are using the DEMO License, and the DEMO License is limited to a maximum of 20 concurrent users.
This means actually that you may have at most 20 concurrent sessions.
Each LSClient of the Java SE Client API holds a connection. This is slightly different from the LightstreamerClient in the JavaScript Client API where you may have many LightstreamerClient sharing underneath the same connection.
The LSClient accepts many subscriptions, so you may use one single LSClient to subscribe to all your tables.
More precisely, each connection is associated with one session, and each session is associated to a single Adapter Set. So, if you have many Adapters, they should belong to the same Adapter Set.
For more details you may also look at
General Concepts and
Java Adapter API Reference , particularly at
LSClient.
hth
Marco