Class TarArchiveSparseEntry

  • All Implemented Interfaces:

    public class TarArchiveSparseEntry
    extends java.lang.Object
    implements TarConstants
    This class represents a sparse entry in a Tar archive.

    The C structure for a sparse entry is:

     struct posix_header {
     struct sparse sp[21]; // TarConstants.SPARSELEN_GNU_SPARSE     - offset 0
     char isextended;      // TarConstants.ISEXTENDEDLEN_GNU_SPARSE - offset 504
    Whereas, "struct sparse" is:
     struct sparse {
     char offset[12];   // offset 0
     char numbytes[12]; // offset 12

    Each such struct describes a block of data that has actually been written to the archive. The offset describes where in the extracted file the data is supposed to start and the numbytes provides the length of the block. When extracting the entry the gaps between the sparse structs are equivalent to areas filled with zero bytes.

    • Constructor Detail

      • TarArchiveSparseEntry

        public TarArchiveSparseEntry​(byte[] headerBuf)
        Construct an entry from an archive's header bytes. File is set to null.
        headerBuf - The header bytes from a tar archive entry.
        Throws: - on unknown format
    • Method Detail

      • isExtended

        public boolean isExtended()
      • getSparseHeaders

        public java.util.List<TarArchiveStructSparse> getSparseHeaders()
        Obtains information about the configuration for the sparse entry.
        information about the configuration for the sparse entry.