Package org.apache.commons.compress.compressors.xz

Class XZUtils

  • public class XZUtils
extends java.lang.Object
    Utility code for the xz compression format.
    Since:
    1.4

    • Field Detail

      • fileNameUtil

        private static final FileNameUtil fileNameUtil

      • HEADER_MAGIC

        private static final byte[] HEADER_MAGIC
        XZ Header Magic Bytes begin a XZ file.

        This is a copy of org.tukaani.xz.XZ.HEADER_MAGIC in XZ for Java version 1.5.

    • Constructor Detail

      • XZUtils

        private XZUtils()
        Private constructor to prevent instantiation of this utility class.

    • Method Detail

      • matches

        public static boolean matches​(byte[] signature,
                              int length)
        Checks if the signature matches what is expected for a .xz file.

        This is more or less a copy of the version found in XZCompressorInputStream but doesn't depend on the presence of XZ for Java.

        Parameters:
        signature - the bytes to check
        length - the number of bytes to check
        Returns:
        true if signature matches the .xz magic bytes, false otherwise
        Since:
        1.9

      • isXZCompressionAvailable

        public static boolean isXZCompressionAvailable()
        Are the classes required to support XZ compression available?
        Returns:
        true if the classes required to support XZ compression are available
        Since:
        1.5

      • internalIsXZCompressionAvailable

        private static boolean internalIsXZCompressionAvailable()

      • isCompressedFilename

        public static boolean isCompressedFilename​(java.lang.String fileName)
        Detects common xz suffixes in the given file name.
        Parameters:
        fileName - name of a file
        Returns:
        true if the file name has a common xz suffix, false otherwise

      • getUncompressedFilename

        public static java.lang.String getUncompressedFilename​(java.lang.String fileName)
        Maps the given name of a xz-compressed file to the name that the file should have after uncompression. Commonly used file type specific suffixes like ".txz" are automatically detected and correctly mapped. For example the name "package.txz" is mapped to "package.tar". And any file names with the generic ".xz" suffix (or any other generic xz suffix) is mapped to a name without that suffix. If no xz suffix is detected, then the file name is returned unmapped.
        Parameters:
        fileName - name of a file
        Returns:
        name of the corresponding uncompressed file

      • getCompressedFilename

        public static java.lang.String getCompressedFilename​(java.lang.String fileName)
        Maps the given file name to the name that the file should have after compression with xz. Common file types with custom suffixes for compressed versions are automatically detected and correctly mapped. For example the name "package.tar" is mapped to "package.txz". If no custom mapping is applicable, then the default ".xz" suffix is appended to the file name.
        Parameters:
        fileName - name of a file
        Returns:
        name of the corresponding compressed file

      • setCacheXZAvailablity

        public static void setCacheXZAvailablity​(boolean doCache)
        Whether to cache the result of the XZ for Java check.

        This defaults to false in an OSGi environment and true otherwise.

        Parameters:
        doCache - whether to cache the result
        Since:
        1.9