Package org.apache.commons.compress.archivers.zip

Class ZipArchiveInputStream

java.lang.Object
java.io.InputStream
java.io.FilterInputStream
org.apache.commons.compress.archivers.ArchiveInputStream<ZipArchiveEntry>
org.apache.commons.compress.archivers.zip.ZipArchiveInputStream
All Implemented Interfaces:
Closeable, AutoCloseable, InputStreamStatistics
Direct Known Subclasses:
JarArchiveInputStream
public class ZipArchiveInputStream extends ArchiveInputStream<ZipArchiveEntry> implements InputStreamStatistics
Implements an input stream that can read Zip archives.

As of Apache Commons Compress it transparently supports Zip64 extensions and thus individual entries and archives larger than 4 GB or with more than 65,536 entries.

The ZipFile class is preferred when reading from files as ZipArchiveInputStream is limited by not being able to read the central directory header before returning entries. In particular ZipArchiveInputStream

  • may return entries that are not part of the central directory at all and shouldn't be considered part of the archive.
  • may return several entries with the same name.
  • will not return internal or external attributes.
  • may return incomplete extra field data.
  • may return unknown sizes and CRC values for entries until the next entry has been reached if the archive uses the data descriptor feature.
See Also:

  • Field Details

    • PREAMBLE_GARBAGE_MAX_SIZE

      public static final int PREAMBLE_GARBAGE_MAX_SIZE
      Maximum size of data in the first local file header.
      See Also:

  • Constructor Details

    • ZipArchiveInputStream

      public ZipArchiveInputStream(InputStream inputStream)
      Constructs an instance using UTF-8 encoding
      Parameters:
      inputStream - the stream to wrap

    • ZipArchiveInputStream

      public ZipArchiveInputStream(InputStream inputStream, String encoding)
      Constructs an instance using the specified encoding
      Parameters:
      inputStream - the stream to wrap
      encoding - the encoding to use for file names, use null for the platform's default encoding
      Since:
      1.5

    • ZipArchiveInputStream

      public ZipArchiveInputStream(InputStream inputStream, String encoding, boolean useUnicodeExtraFields)
      Constructs an instance using the specified encoding
      Parameters:
      inputStream - the stream to wrap
      encoding - the encoding to use for file names, use null for the platform's default encoding
      useUnicodeExtraFields - whether to use InfoZIP Unicode Extra Fields (if present) to set the file names.

    • ZipArchiveInputStream

      public ZipArchiveInputStream(InputStream inputStream, String encoding, boolean useUnicodeExtraFields, boolean allowStoredEntriesWithDataDescriptor)
      Constructs an instance using the specified encoding
      Parameters:
      inputStream - the stream to wrap
      encoding - the encoding to use for file names, use null for the platform's default encoding
      useUnicodeExtraFields - whether to use InfoZIP Unicode Extra Fields (if present) to set the file names.
      allowStoredEntriesWithDataDescriptor - whether the stream will try to read STORED entries that use a data descriptor
      Since:
      1.1

    • ZipArchiveInputStream

      public ZipArchiveInputStream(InputStream inputStream, String encoding, boolean useUnicodeExtraFields, boolean allowStoredEntriesWithDataDescriptor, boolean skipSplitSig)
      Constructs an instance using the specified encoding
      Parameters:
      inputStream - the stream to wrap
      encoding - the encoding to use for file names, use null for the platform's default encoding
      useUnicodeExtraFields - whether to use InfoZIP Unicode Extra Fields (if present) to set the file names.
      allowStoredEntriesWithDataDescriptor - whether the stream will try to read STORED entries that use a data descriptor
      skipSplitSig - Whether the stream will try to skip the zip split signature(08074B50) at the beginning. You will need to set this to true if you want to read a split archive.
      Since:
      1.20

  • Method Details

    • matches

      public static boolean matches(byte[] signature, int length)
      Checks if the signature matches what is expected for a ZIP file. Does not currently handle self-extracting ZIPs which may have arbitrary leading content.
      Parameters:
      signature - the bytes to check
      length - the number of bytes to check
      Returns:
      true, if this stream is a ZIP archive stream, false otherwise

    • canReadEntryData

      public boolean canReadEntryData(ArchiveEntry ae)
      Tests whether this class is able to read the given entry.

      May return false if it is set up to use encryption or a compression method that hasn't been implemented yet.

      Overrides:
      canReadEntryData in class ArchiveInputStream<ZipArchiveEntry>
      Parameters:
      ae - the entry to test.
      Returns:
      This implementation always returns true.
      Since:
      1.1

    • close

      public void close() throws IOException
      Specified by:
      close in interface AutoCloseable
      Specified by:
      close in interface Closeable
      Overrides:
      close in class FilterInputStream
      Throws:
      IOException

    • getCompressedCount

      public long getCompressedCount()
      Description copied from interface: InputStreamStatistics
      Gets the amount of raw or compressed bytes read by the stream.
      Specified by:
      getCompressedCount in interface InputStreamStatistics
      Returns:
      the amount of raw or compressed bytes read by the stream.
      Since:
      1.17

    • getNextEntry

      public ZipArchiveEntry getNextEntry() throws IOException
      Description copied from class: ArchiveInputStream
      Gets the next Archive Entry in this Stream.
      Specified by:
      getNextEntry in class ArchiveInputStream<ZipArchiveEntry>
      Returns:
      the next entry, or null if there are no more entries.
      Throws:
      IOException - if the next entry could not be read.

    • getNextZipEntry

      @Deprecated public ZipArchiveEntry getNextZipEntry() throws IOException
      Deprecated.
      Use getNextEntry().
      Gets the next entry.
      Returns:
      the next entry.
      Throws:
      IOException - if an I/O error occurs.

    • getUncompressedCount

      public long getUncompressedCount()
      Gets the uncompressed count.
      Specified by:
      getUncompressedCount in interface InputStreamStatistics
      Returns:
      the amount of decompressed bytes returned by the stream.
      Since:
      1.17

    • read

      public int read(byte[] buffer, int offset, int length) throws IOException
      Overrides:
      read in class FilterInputStream
      Throws:
      IOException

    • setExtraFieldSupport

      public ZipArchiveInputStream setExtraFieldSupport(Function<ZipShort,ZipExtraField> extraFieldSupport)
      Currently unused. Sets the custom extra fields factory.
      Parameters:
      extraFieldSupport - the lookup function based on extra field header id.
      Returns:
      the archive.

    • skip

      public long skip(long value) throws IOException
      Skips over and discards value bytes of data from this input stream.

      This implementation may end up skipping over some smaller number of bytes, possibly 0, if and only if it reaches the end of the underlying stream.

      The actual number of bytes skipped is returned.

      Overrides:
      skip in class FilterInputStream
      Parameters:
      value - the number of bytes to be skipped.
      Returns:
      the actual number of bytes skipped.
      Throws:
      IOException - - if an I/O error occurs.
      IllegalArgumentException - - if value is negative.