Datasource in jdbc connection pooling not returning connection [duplicate]

Answer 1

You forgot to close the connection

Use a finally statement to close a pooled connection. The following finally block would appear after the try/catch block that applies to the code in which the pooled connection was used:

try {
     Connection con = 
  ds.getConnection(username, password);
     // ... code to use the pooled
     // connection con
 } catch (Exception ex {
     // ... code to handle exceptions
 } finally {
     if (con != null) con.close();
 }

Your datasource reached the maximum connection defined.