public TransactionIsolationLevel getTransactionIsolationLevel() {
        try {
            return TransactionIsolationLevel.valueOf(connection.getTransactionIsolation());
        } catch (SQLException e) {
            throw new UnableToManipulateTransactionIsolationLevelException("unable to access current setting", e);
        }
    }
Obtain the current transaction isolation level.

@return the current isolation level on the underlying connection.
core/src/main/java/org/jdbi/v3/core/Handle.java