private DcerpcHandle rpcHandle;

    // Witness RPC interface
    private static final String WITNESS_INTERFACE_UUID = "ccd8c074-d0e5-4a40-92b4-d074faa6ba28";
    private static final int WITNESS_INTERFACE_VERSION = 1;

    // RPC connection parameters
    private static final int WITNESS_RPC_PORT = 135;
    private static final int WITNESS_RPC_TIMEOUT_MS = 5000;

    // RPC operation numbers

     * @throws IOException if an I/O error occurs during handle closure
     */
    public void close() throws IOException {
        final MsrpcSamrCloseHandle rpc = new MsrpcSamrCloseHandle(this);
        handle.sendrecv(rpc);
        if (rpc.retval != 0) {
            throw new SmbException(rpc.retval, false);
        }
    }

        /** Domain NetBIOS name. */
        public rpc.unicode_string name;
        /** DNS domain name. */
        public rpc.unicode_string dns_domain;
        /** DNS forest name. */
        public rpc.unicode_string dns_forest;
        /** Domain GUID. */
        public rpc.uuid_t domain_guid;
        /** Domain security identifier. */
        public rpc.sid_t sid;

        @Override

        if (this.opened) {
            this.opened = false;
            final samr.SamrCloseHandle rpc = new MsrpcSamrCloseHandle(this);
            this.handle.sendrecv(rpc);
            if (rpc.retval != 0) {
                throw new SmbException(rpc.retval, false);
            }
        }
    }

        // Arrange
        String server = "testServer";
        int access = 123;
        int errorCode = 12345;

        doAnswer(invocation -> {
            MsrpcLsarOpenPolicy2 rpc = invocation.getArgument(0);
            rpc.retval = errorCode; // Simulate RPC error
            return null;
        }).when(mockDcerpcHandle).sendrecv(any(MsrpcLsarOpenPolicy2.class));

        // Act & Assert

        /** Domain NetBIOS name. */
        public rpc.unicode_string name;
        /** DNS domain name. */
        public rpc.unicode_string dns_domain;
        /** DNS forest name. */
        public rpc.unicode_string dns_forest;
        /** Domain GUID. */
        public rpc.uuid_t domain_guid;
        /** Domain security identifier. */
        public rpc.sid_t sid;

        @Override

        public int retval;
        /** The SAM server handle */
        public rpc.policy_handle handle;
        /** The desired access rights to the domain */
        public int access_mask;
        /** The SID of the domain to open */
        public rpc.sid_t sid;
        /** The returned handle to the domain */
        public rpc.policy_handle domain_handle;

        /**
         * Constructs a SamrOpenDomain request.

        public int retval;
        /** The SAM server handle */
        public rpc.policy_handle handle;
        /** The desired access rights to the domain */
        public int access_mask;
        /** The SID of the domain to open */
        public rpc.sid_t sid;
        /** The returned handle to the domain */
        public rpc.policy_handle domain_handle;

        /**
         * Constructs a SamrOpenDomain request.

        lsarpc.LsarDomainInfo domainInfo = new lsarpc.LsarDomainInfo();
        domainInfo.name = new rpc.unicode_string();
        domainInfo.name.length = 10;
        domainInfo.name.maximum_length = 20;
        domainInfo.name.buffer = new short[] { 'T', 'e', 's', 't', '1' };

        // Create a simple test SID
        domainInfo.sid = new rpc.sid_t();
        domainInfo.sid.revision = 1;

        void testPolicyHandleEncode() throws NdrException {
            // Given: A policy handle with test values
            rpc.policy_handle policyHandle = new rpc.policy_handle();
            policyHandle.type = 123;
            policyHandle.uuid = new rpc.uuid_t();
            policyHandle.uuid.time_low = 0x11111111;
            policyHandle.uuid.time_mid = (short) 0x2222;