You don't have one DBCP Connection Pool for multiple databases, you have one pool per database. Each one has its own JDBC URL, connection credentials - and pool settings.
Pools are collections of objects which are essentially identical. So a Connection to Database #1 and a Connection to Database #1 wouldn't make sense. How would you know which database you would be working with if you invoked getConnection on a pool of heterogeneous Connections?
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