private void updateTransactionStatus()

in src/main/java/org/apache/commons/dbcp2/managed/ManagedConnection.java [250:339]
56 lines of code
16 McCabe index (conditional complexity)

    private void updateTransactionStatus() throws SQLException {
        // if there is an active transaction context, assure the transaction context hasn't changed
        if (transactionContext != null && !transactionContext.isTransactionComplete()) {
            if (transactionContext.isActive()) {
                if (transactionContext != transactionRegistry.getActiveTransactionContext()) {
                    throw new SQLException("Connection cannot be used while enlisted in another transaction");
                }
                return;
            }
            // transaction should have been cleared up by TransactionContextListener, but in
            // rare cases another lister could have registered which uses the connection before
            // our listener is called. In that rare case, trigger the transaction complete call now
            transactionComplete();
        }

        // the existing transaction context ended (or we didn't have one), get the active transaction context
        transactionContext = transactionRegistry.getActiveTransactionContext();

        // if there is an active transaction context, and it already has a shared connection, use it
        if (transactionContext != null && transactionContext.getSharedConnection() != null) {
            // A connection for the connection factory has already been enrolled
            // in the transaction, replace our delegate with the enrolled connection

            // return current connection to the pool
            @SuppressWarnings("resource")
            final C connection = getDelegateInternal();
            setDelegate(null);
            if (connection != null && transactionContext.getSharedConnection() != connection) {
                try {
                    pool.returnObject(connection);
                } catch (final Exception e) {
                    // whatever... try to invalidate the connection
                    try {
                        pool.invalidateObject(connection);
                    } catch (final Exception ignored) {
                        // no big deal
                    }
                }
            }

            // add a listener to the transaction context
            transactionContext.addTransactionContextListener(new CompletionListener());

            // Set our delegate to the shared connection. Note that this will
            // always be of type C since it has been shared by another
            // connection from the same pool.
            @SuppressWarnings("unchecked")
            final C shared = (C) transactionContext.getSharedConnection();
            setDelegate(shared);

            // remember that we are using a shared connection, so it can be cleared after the
            // transaction completes
            isSharedConnection = true;
        } else {
            C connection = getDelegateInternal();
            // if our delegate is null, create one
            if (connection == null) {
                try {
                    // borrow a new connection from the pool
                    connection = pool.borrowObject();
                    setDelegate(connection);
                } catch (final Exception e) {
                    throw new SQLException("Unable to acquire a new connection from the pool", e);
                }
            }

            // if we have a transaction, out delegate becomes the shared delegate
            if (transactionContext != null) {
                // add a listener to the transaction context
                transactionContext.addTransactionContextListener(new CompletionListener());

                // register our connection as the shared connection
                try {
                    transactionContext.setSharedConnection(connection);
                } catch (final SQLException e) {
                    // transaction is hosed
                    transactionContext = null;
                    try {
                        pool.invalidateObject(connection);
                    } catch (final Exception ignored) {
                        // we are try but no luck
                    }
                    throw e;
                }
            }
        }
        // autoCommit may have been changed directly on the underlying
        // connection
        clearCachedState();
    }