String str = "string";
        StringBuilder builder = new StringBuilder("builder");
        StringBuffer buffer = new StringBuffer("buffer");
        String result = StringUtil.join(",", str, builder, buffer);
        assertEquals("string,builder,buffer", result);
    }

    @ParameterizedTest
    @DisplayName("Should handle various element counts")

        StringBuilder buffer = new StringBuilder(256);

        Proxy proxy = repository.getProxy();
        if (proxy != null) {
            if (proxy.getUserName() != null) {
                int hash = (proxy.getUserName() + proxy.getPassword()).hashCode();
                buffer.append(hash).append('@');
            }

        return 0;
    }

    @Override
    int readSetupWireFormat(final byte[] buffer, final int bufferIndex, final int len) {
        return 0;
    }

    @Override
    int readParametersWireFormat(final byte[] buffer, final int bufferIndex, final int len) {
        return 0;
    }

    @Override
    int readDataWireFormat(final byte[] buffer, final int bufferIndex, final int len) {
        if (pipe.pipeIn != null) {

            verify(mockNdrBuffer).enc_ndr_short((short) 6);
            verify(mockNdrBuffer).enc_ndr_referent(entry.name.buffer, 1);
        }

        @Test
        @DisplayName("Should encode entry with null buffer")
        void testEncodeNullBuffer() throws NdrException {
            // Given: SAM entry with null buffer
            samr.SamrSamEntry entry = new samr.SamrSamEntry();
            entry.idx = 1;

        IgnoreCloseInputStream stream = new IgnoreCloseInputStream(underlyingStream);

        byte[] buffer = new byte[5];
        int bytesRead = stream.read(buffer);

        assertEquals(5, bytesRead);
        assertEquals("Hello", new String(buffer));
    }

    public void test_readBytesWithOffset_delegatesToUnderlying() throws IOException {

    }

    @Test
    void testVerifySignature() {
        byte[] buffer = new byte[] { 1, 2, 3 };
        int offset = 0;
        int size = 3;

        // Simulate successful verification
        when(mockResponse.verifySignature(buffer, offset, size)).thenReturn(true);
        assertTrue(mockResponse.verifySignature(buffer, offset, size));

        // Simulate failed verification

     *
     * @see jcifs.internal.smb2.ServerMessageBlock2#readBytesWireFormat(byte[], int)
     */
    @Override
    protected int readBytesWireFormat(final byte[] buffer, final int bufferIndex) throws SMBProtocolDecodingException {
        final int structureSize = SMBUtil.readInt2(buffer, bufferIndex);
        if (structureSize != 4) {
            throw new SMBProtocolDecodingException("Expected structureSize = 4");
        }
        return 4;

     *
     * @see jcifs.internal.smb2.ServerMessageBlock2#readBytesWireFormat(byte[], int)
     */
    @Override
    protected int readBytesWireFormat(final byte[] buffer, final int bufferIndex) throws SMBProtocolDecodingException {
        final int structureSize = SMBUtil.readInt2(buffer, bufferIndex);
        if (structureSize != 4) {
            throw new SMBProtocolDecodingException("Structure size != 4");
        }

        return 4;
    }

            byte[] buffer = new byte[20];

            int bytesRead = Transport.readn(is, buffer, 0, 5);
            assertEquals(5, bytesRead);
            assertArrayEquals("Hello".getBytes(), java.util.Arrays.copyOfRange(buffer, 0, 5));
        }

        @Test
        @DisplayName("readn should throw IOException when buffer too short")
        void shouldThrowWhenBufferTooShort() {

        final int start = bufferIndex;
        if (in.read(buffer, bufferIndex, length) != length) {
            throw new IOException("invalid session request wire format");
        }
        bufferIndex += calledName.readWireFormat(buffer, bufferIndex);
        bufferIndex += callingName.readWireFormat(buffer, bufferIndex);
        return bufferIndex - start;