public static String createLinkFailureMessageBasedOnHeuristics()

in src/main/core-api/java/com/mysql/cj/exceptions/ExceptionFactory.java [187:299]
85 lines of code
25 McCabe index (conditional complexity)

    public static String createLinkFailureMessageBasedOnHeuristics(PropertySet propertySet, ServerSession serverSession,
            PacketSentTimeHolder packetSentTimeHolder, PacketReceivedTimeHolder packetReceivedTimeHolder, Throwable underlyingException) {
        long serverTimeoutSeconds = 0;
        boolean isInteractiveClient = false;

        long lastPacketReceivedTimeMs = packetReceivedTimeHolder == null ? 0L : packetReceivedTimeHolder.getLastPacketReceivedTime();
        long lastPacketSentTimeMs = packetSentTimeHolder.getLastPacketSentTime();
        if (lastPacketSentTimeMs > lastPacketReceivedTimeMs) {
            lastPacketSentTimeMs = packetSentTimeHolder.getPreviousPacketSentTime();
        }

        if (propertySet != null) {
            isInteractiveClient = propertySet.getBooleanProperty(PropertyKey.interactiveClient).getValue();

            String serverTimeoutSecondsStr = null;

            if (serverSession != null) {
                serverTimeoutSecondsStr = isInteractiveClient ? serverSession.getServerVariable("interactive_timeout")
                        : serverSession.getServerVariable("wait_timeout");
            }

            if (serverTimeoutSecondsStr != null) {
                try {
                    serverTimeoutSeconds = Long.parseLong(serverTimeoutSecondsStr);
                } catch (NumberFormatException nfe) {
                    serverTimeoutSeconds = 0;
                }
            }
        }

        StringBuilder exceptionMessageBuf = new StringBuilder();

        long nowMs = System.currentTimeMillis();

        if (lastPacketSentTimeMs == 0) {
            lastPacketSentTimeMs = nowMs;
        }

        long timeSinceLastPacketSentMs = nowMs - lastPacketSentTimeMs;
        long timeSinceLastPacketSeconds = timeSinceLastPacketSentMs / 1000;

        long timeSinceLastPacketReceivedMs = nowMs - lastPacketReceivedTimeMs;

        int dueToTimeout = DUE_TO_TIMEOUT_FALSE;

        StringBuilder timeoutMessageBuf = null;

        if (serverTimeoutSeconds != 0) {
            if (timeSinceLastPacketSeconds > serverTimeoutSeconds) {
                dueToTimeout = DUE_TO_TIMEOUT_TRUE;

                timeoutMessageBuf = new StringBuilder();
                timeoutMessageBuf.append(Messages.getString("CommunicationsException.2"));
                timeoutMessageBuf.append(Messages.getString(isInteractiveClient ? "CommunicationsException.4" : "CommunicationsException.3"));
            }

        } else if (timeSinceLastPacketSeconds > DEFAULT_WAIT_TIMEOUT_SECONDS) {
            dueToTimeout = DUE_TO_TIMEOUT_MAYBE;

            timeoutMessageBuf = new StringBuilder();
            timeoutMessageBuf.append(Messages.getString("CommunicationsException.5"));
            timeoutMessageBuf.append(Messages.getString("CommunicationsException.6"));
            timeoutMessageBuf.append(Messages.getString("CommunicationsException.7"));
            timeoutMessageBuf.append(Messages.getString("CommunicationsException.8"));
        }

        if (dueToTimeout == DUE_TO_TIMEOUT_TRUE || dueToTimeout == DUE_TO_TIMEOUT_MAYBE) {

            exceptionMessageBuf.append(lastPacketReceivedTimeMs != 0
                    ? Messages.getString("CommunicationsException.ServerPacketTimingInfo",
                            new Object[] { Long.valueOf(timeSinceLastPacketReceivedMs), Long.valueOf(timeSinceLastPacketSentMs) })
                    : Messages.getString("CommunicationsException.ServerPacketTimingInfoNoRecv", new Object[] { Long.valueOf(timeSinceLastPacketSentMs) }));

            if (timeoutMessageBuf != null) {
                exceptionMessageBuf.append(timeoutMessageBuf);
            }

            exceptionMessageBuf.append(Messages.getString("CommunicationsException.11"));
            exceptionMessageBuf.append(Messages.getString("CommunicationsException.12"));
            exceptionMessageBuf.append(Messages.getString("CommunicationsException.13"));

        } else {
            //
            // Attempt to determine the reason for the underlying exception (we can only make a best-guess here)
            //
            if (underlyingException instanceof BindException) {
                String localSocketAddress = propertySet.getStringProperty(PropertyKey.localSocketAddress).getValue();
                boolean interfaceNotAvaliable;
                try {
                    interfaceNotAvaliable = localSocketAddress != null && NetworkInterface.getByName(localSocketAddress) == null;
                } catch (SocketException e1) {
                    interfaceNotAvaliable = false;
                }
                exceptionMessageBuf.append(interfaceNotAvaliable ? Messages.getString("CommunicationsException.LocalSocketAddressNotAvailable")
                        : Messages.getString("CommunicationsException.TooManyClientConnections"));
            }
        }

        if (exceptionMessageBuf.length() == 0) {
            // We haven't figured out a good reason, so copy it.
            exceptionMessageBuf.append(Messages.getString("CommunicationsException.20"));

            if (propertySet.getBooleanProperty(PropertyKey.maintainTimeStats).getValue() && !propertySet.getBooleanProperty(PropertyKey.paranoid).getValue()) {
                exceptionMessageBuf.append("\n\n");
                exceptionMessageBuf.append(lastPacketReceivedTimeMs != 0
                        ? Messages.getString("CommunicationsException.ServerPacketTimingInfo",
                                new Object[] { Long.valueOf(timeSinceLastPacketReceivedMs), Long.valueOf(timeSinceLastPacketSentMs) })
                        : Messages.getString("CommunicationsException.ServerPacketTimingInfoNoRecv", new Object[] { Long.valueOf(timeSinceLastPacketSentMs) }));
            }
        }

        return exceptionMessageBuf.toString();
    }