private static boolean closeDirectByteBufferPrivileged()

in common/src/main/java/org/mvndaemon/mvnd/common/BufferHelper.java [138:234]
78 lines of code
23 McCabe index (conditional complexity)

    private static boolean closeDirectByteBufferPrivileged(final ByteBuffer byteBuffer, final Consumer<String> log) {
        if (!byteBuffer.isDirect()) {
            // Nothing to do
            return true;
        }
        try {
            if (PRE_JAVA_9) {
                if (attachmentMethod == null) {
                    if (log != null) {
                        log.accept("Could not unmap ByteBuffer, attachmentMethod == null");
                    }
                    return false;
                }
                // Make sure duplicates and slices are not cleaned, since this can result in duplicate
                // attempts to clean the same buffer, which trigger a crash with:
                // "A fatal error has been detected by the Java Runtime Environment: EXCEPTION_ACCESS_VIOLATION"
                // See: https://stackoverflow.com/a/31592947/3950982
                if (attachmentMethod.invoke(byteBuffer) != null) {
                    // Buffer is a duplicate or slice
                    return false;
                }
                // Invoke ((DirectBuffer) byteBuffer).cleaner().clean()
                if (directByteBufferCleanerMethod == null) {
                    if (log != null) {
                        log.accept("Could not unmap ByteBuffer, cleanerMethod == null");
                    }
                    return false;
                }
                try {
                    directByteBufferCleanerMethod.setAccessible(true);
                } catch (final Exception e) {
                    if (log != null) {
                        log.accept("Could not unmap ByteBuffer, cleanerMethod.setAccessible(true) failed");
                    }
                    return false;
                }
                final Object cleanerInstance = directByteBufferCleanerMethod.invoke(byteBuffer);
                if (cleanerInstance == null) {
                    if (log != null) {
                        log.accept("Could not unmap ByteBuffer, cleaner == null");
                    }
                    return false;
                }
                if (cleanerCleanMethod == null) {
                    if (log != null) {
                        log.accept("Could not unmap ByteBuffer, cleanMethod == null");
                    }
                    return false;
                }
                try {
                    cleanerCleanMethod.invoke(cleanerInstance);
                    return true;
                } catch (final Exception e) {
                    if (log != null) {
                        log.accept("Could not unmap ByteBuffer, cleanMethod.invoke(cleaner) failed: " + e);
                    }
                    return false;
                }
                //    } else if (memorySegmentOfByteBufferMethod != null) {
                //        // JDK 14+
                //        final Object memorySegment = memorySegmentOfByteBufferMethod.invoke(null, byteBuffer);
                //        if (memorySegment == null) {
                //            if (log != null) {
                //                log.log("Got null MemorySegment, could not unmap ByteBuffer");
                //            }
                //            return false;
                //        }
                //        memorySegmentCloseMethod.invoke(memorySegment);
                //        return true;
            } else {
                if (theUnsafe == null) {
                    if (log != null) {
                        log.accept("Could not unmap ByteBuffer, theUnsafe == null");
                    }
                    return false;
                }
                if (cleanerCleanMethod == null) {
                    if (log != null) {
                        log.accept("Could not unmap ByteBuffer, cleanMethod == null");
                    }
                    return false;
                }
                try {
                    cleanerCleanMethod.invoke(theUnsafe, byteBuffer);
                    return true;
                } catch (final IllegalArgumentException e) {
                    // Buffer is a duplicate or slice
                    return false;
                }
            }
        } catch (final ReflectiveOperationException | SecurityException e) {
            if (log != null) {
                log.accept("Could not unmap ByteBuffer: " + e);
            }
            return false;
        }
    }