org.apache.commons.compress.archivers.dump

Class DumpArchiveInputStream

  • All Implemented Interfaces:
    Closeable, AutoCloseable 

    public class DumpArchiveInputStream
extends ArchiveInputStream
    The DumpArchiveInputStream reads a UNIX dump archive as an InputStream. Methods are provided to position at each successive entry in the archive, and the read each entry as a normal input stream using read(). There doesn't seem to exist a hint on the encoding of string values in any piece documentation. Given the main purpose of dump/restore is backing up a system it seems very likely the format uses the current default encoding of the system.

    • Field Detail

      • raw

        protected org.apache.commons.compress.archivers.dump.TapeInputStream raw

    • Constructor Detail

      • DumpArchiveInputStream

        public DumpArchiveInputStream(InputStream is,
                              String encoding)
                       throws ArchiveException
        Constructor.
        Parameters:
        is -
        encoding - the encoding to use for file names, use null for the platform's default encoding
        Throws:
        ArchiveException
        Since:
        1.6

    • Method Detail

      • getBytesRead

        public long getBytesRead()
        Description copied from class: ArchiveInputStream
        Returns the current number of bytes read from this stream.
        Overrides:
        getBytesRead in class  ArchiveInputStream
        Returns:
        the number of read bytes

      • getSummary

        public DumpArchiveSummary getSummary()
        Return the archive summary information.

      • read

        public int read(byte[] buf,
                int off,
                int len)
         throws IOException
        Reads bytes from the current dump archive entry. This method is aware of the boundaries of the current entry in the archive and will deal with them as if they were this stream's start and EOF.
        Overrides:
        read in class  InputStream
        Parameters:
        buf - The buffer into which to place bytes read.
        off - The offset at which to place bytes read.
        len - The number of bytes to read.
        Returns:
        The number of bytes read, or -1 at EOF.
        Throws:
        IOException - on error

      • matches

        public static boolean matches(byte[] buffer,
                              int length)
        Look at the first few bytes of the file to decide if it's a dump archive. With 32 bytes we can look at the magic value, with a full 1k we can verify the checksum.