public CloseableHandle open()

in sshd-sftp/src/main/java/org/apache/sshd/sftp/client/impl/AbstractSftpClient.java [513:591]
71 lines of code
22 McCabe index (conditional complexity)

    public CloseableHandle open(String path, Collection<OpenMode> options) throws IOException {
        if (!isOpen()) {
            throw new IOException("open(" + path + ")[" + options + "] client is closed");
        }

        /*
         * Be consistent with FileChannel#open - if no mode specified then READ is assumed
         */
        if (GenericUtils.isEmpty(options)) {
            options = EnumSet.of(OpenMode.Read);
        }

        Buffer buffer = new ByteArrayBuffer(path.length() + Long.SIZE /* some extra fields */, false);
        buffer = putReferencedName(SftpConstants.SSH_FXP_OPEN, buffer, path, 0);

        int version = getVersion();
        int mode = 0;
        if (version < SftpConstants.SFTP_V5) {
            for (OpenMode m : options) {
                switch (m) {
                    case Read:
                        mode |= SftpConstants.SSH_FXF_READ;
                        break;
                    case Write:
                        mode |= SftpConstants.SSH_FXF_WRITE;
                        break;
                    case Append:
                        mode |= SftpConstants.SSH_FXF_APPEND;
                        break;
                    case Create:
                        mode |= SftpConstants.SSH_FXF_CREAT;
                        break;
                    case Truncate:
                        mode |= SftpConstants.SSH_FXF_TRUNC;
                        break;
                    case Exclusive:
                        mode |= SftpConstants.SSH_FXF_EXCL;
                        break;
                    default: // do nothing
                }
            }
        } else {
            int access = 0;
            if (options.contains(OpenMode.Read)) {
                access |= SftpConstants.ACE4_READ_DATA | SftpConstants.ACE4_READ_ATTRIBUTES;
            }
            if (options.contains(OpenMode.Write)) {
                access |= SftpConstants.ACE4_WRITE_DATA | SftpConstants.ACE4_WRITE_ATTRIBUTES;
            }
            if (options.contains(OpenMode.Append)) {
                access |= SftpConstants.ACE4_APPEND_DATA;
                mode |= SftpConstants.SSH_FXF_APPEND_DATA;
            }
            buffer.putInt(access);

            if (options.contains(OpenMode.Create) && options.contains(OpenMode.Exclusive)) {
                mode |= SftpConstants.SSH_FXF_CREATE_NEW;
            } else if (options.contains(OpenMode.Create) && options.contains(OpenMode.Truncate)) {
                mode |= SftpConstants.SSH_FXF_CREATE_TRUNCATE;
            } else if (options.contains(OpenMode.Create)) {
                mode |= SftpConstants.SSH_FXF_OPEN_OR_CREATE;
            } else if (options.contains(OpenMode.Truncate)) {
                mode |= SftpConstants.SSH_FXF_TRUNCATE_EXISTING;
            } else {
                mode |= SftpConstants.SSH_FXF_OPEN_EXISTING;
            }
        }
        buffer.putInt(mode);
        buffer = writeAttributes(SftpConstants.SSH_FXP_OPEN, buffer, fileOpenAttributes);

        if (log.isDebugEnabled()) {
            log.debug("open({}): send SSH_FXP_OPEN {} mode={}", getClientChannel(), path, String.format("0x%04x", mode));
        }
        CloseableHandle handle = new DefaultCloseableHandle(this, path, checkHandle(SftpConstants.SSH_FXP_OPEN, buffer));
        if (log.isTraceEnabled()) {
            log.trace("open({})[{}] options={}: {}", getClientChannel(), path, options, handle);
        }
        return handle;
    }