class ReadBytesWireFormatTests {

        @Test
        @DisplayName("Should read valid structure size of 4")
        void testReadBytesWireFormatValid() throws SMBProtocolDecodingException {
            byte[] buffer = new byte[1024];
            int bufferIndex = 100;

            // Write structure size = 4
            SMBUtil.writeInt2(4, buffer, bufferIndex);

    @Test
    @DisplayName("Test readBytesWireFormat with valid structure size")
    void testReadBytesWireFormatValidStructureSize() throws Exception {
        response = new Smb2QueryDirectoryResponse(mockConfig, Smb2QueryDirectoryRequest.FILE_BOTH_DIRECTORY_INFO);

        byte[] buffer = new byte[512];
        int bufferIndex = 0;

        // Set structure size to 9 (valid)
        SMBUtil.writeInt2(9, buffer, bufferIndex);

            assertArrayEquals(testFileId, Arrays.copyOfRange(buffer, 8, 24));

            // Verify total bytes written (structure + lock data)
            assertEquals(24 + 24, bytesWritten); // 24 for structure, 24 for lock
        }

        @Test
        @DisplayName("Should write request structure correctly with multiple locks")
        void testWriteBytesWireFormatMultipleLocks() {

            int read = resp.readBytesWireFormat(buffer, start);

            // Assert
            assertEquals(4, read, "Should return the fixed structure size (4)");
        }

        @ParameterizedTest
        @ValueSource(ints = { 0, 1, 7 })
        @DisplayName("Throws when structure size is not 4")
        void throws_whenStructureSizeIsNotFour(int size) {
            // Arrange
            byte[] buffer = new byte[2];

        byte[] buffer = new byte[512];
        int offset = 0;

        // Set header start position for the response
        setHeaderStart(response, 64);

        // Write structure header (9 bytes)
        SMBUtil.writeInt2(9, buffer, offset); // Structure size
        SMBUtil.writeInt2(80 - 64, buffer, offset + 2); // Buffer offset (relative to header)
        SMBUtil.writeInt4(50, buffer, offset + 4); // Total length of notification data

            try {
                Pac pac = new Pac(pacData, keys);
                assertNotNull(pac.getServerSignature());
                assertNotNull(pac.getKdcSignature());
            } catch (PACDecodingException e) {
                // Expected due to invalid logon info structure
                assertNotNull(e.getMessage());
            }

 */
package jcifs.internal.smb2.rdma;

import jcifs.internal.util.SMBUtil;

/**
 * SMB2 RDMA Transform structure for READ/WRITE channel info.
 *
 * As per MS-SMB2 2.2.13.1.1 and 2.2.21.1.1
 */
public class Smb2RdmaTransform {

    // SMB_DIRECT_BUFFER_DESCRIPTOR_V1 structure
    private long offset; // 8 bytes: Offset within registered buffer
    private int token; // 4 bytes: RDMA provider token

        // Then
        // The writeBytesWireFormat writes the structure and calculates padding
        // Base structure: 24 bytes, then pad8 alignment, then token: 5 bytes
        // Total bytes written includes padding for 8-byte alignment
        int expectedBytesWritten = 35;
        assertEquals(expectedBytesWritten, bytesWritten);

        // Verify structure

This way, its schema will show up in the API docs user interface:

<img src="/img/tutorial/dataclasses/image01.png">

## Dataclasses in Nested Data Structures { #dataclasses-in-nested-data-structures }

You can also combine `dataclasses` with other type annotations to make nested data structures.

        @Test
        @DisplayName("Should read valid structure with size 4")
        void testReadBytesWireFormatValid() throws SMBProtocolDecodingException {
            // Given
            byte[] buffer = new byte[10];
            int bufferIndex = 2;
            SMBUtil.writeInt2(4, buffer, bufferIndex); // Write structure size = 4
            SMBUtil.writeInt2(0, buffer, bufferIndex + 2); // Reserved field