securityDescriptorBytes[21] = 0; // sbz1
        securityDescriptorBytes[22] = 8; // ACL size (low byte)
        securityDescriptorBytes[23] = 0; // ACL size (high byte)
        securityDescriptorBytes[24] = 0; // ACE count (low byte) - 0 ACEs
        securityDescriptorBytes[25] = 0; // ACE count (high byte)
        securityDescriptorBytes[26] = 0; // sbz2 (low byte)

        StringBuilder sb2 = new StringBuilder("second");
        String result = StringUtil.join(",", sb1, sb2);
        assertEquals("first,second", result);
    }

    @Test
    @DisplayName("Should handle StringBuffer as CharSequence")
    void testJoinWithStringBuffer() {
        StringBuffer sb1 = new StringBuffer("alpha");
        StringBuffer sb2 = new StringBuffer("beta");

go", "src/compress/bzip2/testdata/Isaac.Newton-Opticks.txt.bz2", "src/compress/bzip2/testdata/e.txt.bz2", "src/compress/bzip2/testdata/fail-issue5747.bz2", "src/compress/bzip2/testdata/pass-random1.bin", "src/compress/bzip2/testdata/pass-random1.bz2", "src/compress/bzip2/testdata/pass-random2.bin", "src/compress/bzip2/testdata/pass-random2.bz2", "src/compress/bzip2/testdata/pass-sawtooth.bz2", "src/compress/bzip2/testdata/random.data.bz2", "src/compress/flate/deflate.go", "src/compress/flate/deflate_test.go",...

Decompressing incompressible data has no significant performance impact.

Below is a list of common files and content-types which are typically not suitable for compression.

- Extensions

 | `gz`  | (GZIP)      |
 | `bz2` | (BZIP2)     |
 | `rar` | (WinRAR)    |
 | `zip` | (ZIP)       |
 | `7z`  | (7-Zip)     |
 | `xz`  | (LZMA)      |
 | `mp4` | (MP4)       |
 | `mkv` | (MKV media) |
 | `mov` | (MOV)       |

        response = spy(response);
        when(response.getHeaderStart()).thenReturn(0);

        // Write minimal SecurityDescriptor header (20 bytes)
        buffer[20] = 1; // Revision
        buffer[21] = 0; // Sbz1
        SMBUtil.writeInt2(0x8004, buffer, 22); // Control flags
        SMBUtil.writeInt4(0, buffer, 24); // Owner offset
        SMBUtil.writeInt4(0, buffer, 28); // Group offset