Module java.base
Package java.util.zip

Class ZipInputStream

java.lang.Object
java.io.InputStream
java.io.FilterInputStream
java.util.zip.InflaterInputStream
java.util.zip.ZipInputStream
All Implemented Interfaces:
Closeable, AutoCloseable
Direct Known Subclasses:
JarInputStream
public class ZipInputStream extends InflaterInputStream
This class implements an input stream filter for reading files in the ZIP file format. Includes support for both compressed and uncompressed entries.
Since:
1.1

  • Field Summary

    Fields
    Modifier and Type
    Field
    Description
    static final int
    CENATT
    Central directory (CEN) header internal file attributes field offset.
    static final int
    CENATX
    Central directory (CEN) header external file attributes field offset.
    static final int
    CENCOM
    Central directory (CEN) header comment length field offset.
    static final int
    CENCRC
    Central directory (CEN) header uncompressed file crc-32 value field offset.
    static final int
    CENDSK
    Central directory (CEN) header disk number start field offset.
    static final int
    CENEXT
    Central directory (CEN) header extra field length field offset.
    static final int
    CENFLG
    Central directory (CEN) header encrypt, decrypt flags field offset.
    static final int
    CENHDR
    Central directory (CEN) header size in bytes (including signature).
    static final int
    CENHOW
    Central directory (CEN) header compression method field offset.
    static final int
    CENLEN
    Central directory (CEN) header uncompressed size field offset.
    static final int
    CENNAM
    Central directory (CEN) header filename length field offset.
    static final int
    CENOFF
    Central directory (CEN) header LOC header offset field offset.
    static final long
    CENSIG
    Central directory (CEN) header signature.
    static final int
    CENSIZ
    Central directory (CEN) header compressed size field offset.
    static final int
    CENTIM
    Central directory (CEN) header modification time field offset.
    static final int
    CENVEM
    Central directory (CEN) header version made by field offset.
    static final int
    CENVER
    Central directory (CEN) header version needed to extract field offset.
    static final int
    ENDCOM
    End of central directory (END) header zip file comment length field offset.
    static final int
    ENDHDR
    End of central directory (END) header size in bytes (including signature).
    static final int
    ENDOFF
    End of central directory (END) header offset for the first CEN header field offset.
    static final long
    ENDSIG
    End of central directory (END) header signature.
    static final int
    ENDSIZ
    End of central directory (END) header central directory size in bytes field offset.
    static final int
    ENDSUB
    End of central directory (END) header number of entries on this disk field offset.
    static final int
    ENDTOT
    End of central directory (END) header total number of entries field offset.
    static final int
    EXTCRC
    Extra local (EXT) header uncompressed file crc-32 value field offset.
    static final int
    EXTHDR
    Extra local (EXT) header size in bytes (including signature).
    static final int
    EXTLEN
    Extra local (EXT) header uncompressed size field offset.
    static final long
    EXTSIG
    Extra local (EXT) header signature.
    static final int
    EXTSIZ
    Extra local (EXT) header compressed size field offset.
    static final int
    LOCCRC
    Local file (LOC) header uncompressed file crc-32 value field offset.
    static final int
    LOCEXT
    Local file (LOC) header extra field length field offset.
    static final int
    LOCFLG
    Local file (LOC) header general purpose bit flag field offset.
    static final int
    LOCHDR
    Local file (LOC) header size in bytes (including signature).
    static final int
    LOCHOW
    Local file (LOC) header compression method field offset.
    static final int
    LOCLEN
    Local file (LOC) header uncompressed size field offset.
    static final int
    LOCNAM
    Local file (LOC) header filename length field offset.
    static final long
    LOCSIG
    Local file (LOC) header signature.
    static final int
    LOCSIZ
    Local file (LOC) header compressed size field offset.
    static final int
    LOCTIM
    Local file (LOC) header modification time field offset.
    static final int
    LOCVER
    Local file (LOC) header version needed to extract field offset.

    Fields declared in class java.util.zip.InflaterInputStream

    buf, inf, len

    Fields declared in class java.io.FilterInputStream

    in

  • Constructor Summary

    Constructors
    Constructor
    Description
    ZipInputStream(InputStream in)
    Creates a new ZIP input stream.
    ZipInputStream(InputStream in, Charset charset)
    Creates a new ZIP input stream.

  • Method Summary

    Modifier and Type
    Method
    Description
    int
    available()
    Returns 0 after EOF has reached for the current entry data, otherwise always return 1.
    void
    close()
    Closes this input stream and releases any system resources associated with the stream.
    void
    closeEntry()
    Closes the current ZIP entry and positions the stream for reading the next entry.
    protected ZipEntry
    createZipEntry(String name)
    Creates a new ZipEntry object for the specified entry name.
    ZipEntry
    getNextEntry()
    Reads the next ZIP file entry and positions the stream at the beginning of the entry data.
    int
    read(byte[] b, int off, int len)
    Reads from the current ZIP entry into an array of bytes.
    long
    skip(long n)
    Skips specified number of bytes in the current ZIP entry.

    Methods declared in class java.util.zip.InflaterInputStream

    fill, mark, markSupported, read, reset

    Methods declared in class java.io.FilterInputStream

    read

    Methods declared in class java.io.InputStream

    nullInputStream, readAllBytes, readNBytes, readNBytes, skipNBytes, transferTo

    Methods declared in class java.lang.Object

    clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

  • Field Details

    • LOCSIG

      static final long LOCSIG
      Local file (LOC) header signature.
      See Also:

    • EXTSIG

      static final long EXTSIG
      Extra local (EXT) header signature.
      See Also:

    • CENSIG

      static final long CENSIG
      Central directory (CEN) header signature.
      See Also:

    • ENDSIG

      static final long ENDSIG
      End of central directory (END) header signature.
      See Also:

    • LOCHDR

      static final int LOCHDR
      Local file (LOC) header size in bytes (including signature).
      See Also:

    • EXTHDR

      static final int EXTHDR
      Extra local (EXT) header size in bytes (including signature).
      See Also:

    • CENHDR

      static final int CENHDR
      Central directory (CEN) header size in bytes (including signature).
      See Also:

    • ENDHDR

      static final int ENDHDR
      End of central directory (END) header size in bytes (including signature).
      See Also:

    • LOCVER

      static final int LOCVER
      Local file (LOC) header version needed to extract field offset.
      See Also:

    • LOCFLG

      static final int LOCFLG
      Local file (LOC) header general purpose bit flag field offset.
      See Also:

    • LOCHOW

      static final int LOCHOW
      Local file (LOC) header compression method field offset.
      See Also:

    • LOCTIM

      static final int LOCTIM
      Local file (LOC) header modification time field offset.
      See Also:

    • LOCCRC

      static final int LOCCRC
      Local file (LOC) header uncompressed file crc-32 value field offset.
      See Also:

    • LOCSIZ

      static final int LOCSIZ
      Local file (LOC) header compressed size field offset.
      See Also:

    • LOCLEN

      static final int LOCLEN
      Local file (LOC) header uncompressed size field offset.
      See Also:

    • LOCNAM

      static final int LOCNAM
      Local file (LOC) header filename length field offset.
      See Also:

    • LOCEXT

      static final int LOCEXT
      Local file (LOC) header extra field length field offset.
      See Also:

    • EXTCRC

      static final int EXTCRC
      Extra local (EXT) header uncompressed file crc-32 value field offset.
      See Also:

    • EXTSIZ

      static final int EXTSIZ
      Extra local (EXT) header compressed size field offset.
      See Also:

    • EXTLEN

      static final int EXTLEN
      Extra local (EXT) header uncompressed size field offset.
      See Also:

    • CENVEM

      static final int CENVEM
      Central directory (CEN) header version made by field offset.
      See Also:

    • CENVER

      static final int CENVER
      Central directory (CEN) header version needed to extract field offset.
      See Also:

    • CENFLG

      static final int CENFLG
      Central directory (CEN) header encrypt, decrypt flags field offset.
      See Also:

    • CENHOW

      static final int CENHOW
      Central directory (CEN) header compression method field offset.
      See Also:

    • CENTIM

      static final int CENTIM
      Central directory (CEN) header modification time field offset.
      See Also:

    • CENCRC

      static final int CENCRC
      Central directory (CEN) header uncompressed file crc-32 value field offset.
      See Also:

    • CENSIZ

      static final int CENSIZ
      Central directory (CEN) header compressed size field offset.
      See Also:

    • CENLEN

      static final int CENLEN
      Central directory (CEN) header uncompressed size field offset.
      See Also:

    • CENNAM

      static final int CENNAM
      Central directory (CEN) header filename length field offset.
      See Also:

    • CENEXT

      static final int CENEXT
      Central directory (CEN) header extra field length field offset.
      See Also:

    • CENCOM

      static final int CENCOM
      Central directory (CEN) header comment length field offset.
      See Also:

    • CENDSK

      static final int CENDSK
      Central directory (CEN) header disk number start field offset.
      See Also:

    • CENATT

      static final int CENATT
      Central directory (CEN) header internal file attributes field offset.
      See Also:

    • CENATX

      static final int CENATX
      Central directory (CEN) header external file attributes field offset.
      See Also:

    • CENOFF

      static final int CENOFF
      Central directory (CEN) header LOC header offset field offset.
      See Also:

    • ENDSUB

      static final int ENDSUB
      End of central directory (END) header number of entries on this disk field offset.
      See Also:

    • ENDTOT

      static final int ENDTOT
      End of central directory (END) header total number of entries field offset.
      See Also:

    • ENDSIZ

      static final int ENDSIZ
      End of central directory (END) header central directory size in bytes field offset.
      See Also:

    • ENDOFF

      static final int ENDOFF
      End of central directory (END) header offset for the first CEN header field offset.
      See Also:

    • ENDCOM

      static final int ENDCOM
      End of central directory (END) header zip file comment length field offset.
      See Also:

  • Constructor Details

    • ZipInputStream

      public ZipInputStream(InputStream in)
      Creates a new ZIP input stream.

      The UTF-8 charset is used to decode the entry names.

      Parameters:
      in - the actual input stream

    • ZipInputStream

      public ZipInputStream(InputStream in, Charset charset)
      Creates a new ZIP input stream.
      Parameters:
      in - the actual input stream
      charset - The charset to be used to decode the ZIP entry name (ignored if the language encoding bit of the ZIP entry's general purpose bit flag is set).
      Since:
      1.7

  • Method Details

    • getNextEntry

      public ZipEntry getNextEntry() throws IOException
      Reads the next ZIP file entry and positions the stream at the beginning of the entry data.
      Returns:
      the next ZIP file entry, or null if there are no more entries
      Throws:
      ZipException - if a ZIP file error has occurred
      IOException - if an I/O error has occurred

    • closeEntry

      public void closeEntry() throws IOException
      Closes the current ZIP entry and positions the stream for reading the next entry.
      Throws:
      ZipException - if a ZIP file error has occurred
      IOException - if an I/O error has occurred

    • available

      public int available() throws IOException
      Returns 0 after EOF has reached for the current entry data, otherwise always return 1.

      Programs should not count on this method to return the actual number of bytes that could be read without blocking.

      Overrides:
      available in class InflaterInputStream
      Returns:
      1 before EOF and 0 after EOF has reached for current entry.
      Throws:
      IOException - if an I/O error occurs.

    • read

      public int read(byte[] b, int off, int len) throws IOException
      Reads from the current ZIP entry into an array of bytes. If len is not zero, the method blocks until some input is available; otherwise, no bytes are read and 0 is returned.
      Overrides:
      read in class InflaterInputStream
      Parameters:
      b - the buffer into which the data is read
      off - the start offset in the destination array b
      len - the maximum number of bytes read
      Returns:
      the actual number of bytes read, or -1 if the end of the entry is reached
      Throws:
      NullPointerException - if b is null.
      IndexOutOfBoundsException - if off is negative, len is negative, or len is greater than b.length - off
      ZipException - if a ZIP file error has occurred
      IOException - if an I/O error has occurred
      See Also:

    • skip

      public long skip(long n) throws IOException
      Skips specified number of bytes in the current ZIP entry.
      Overrides:
      skip in class InflaterInputStream
      Parameters:
      n - the number of bytes to skip
      Returns:
      the actual number of bytes skipped
      Throws:
      ZipException - if a ZIP file error has occurred
      IOException - if an I/O error has occurred
      IllegalArgumentException - if n < 0
      See Also:

    • close

      public void close() throws IOException
      Closes this input stream and releases any system resources associated with the stream.
      Specified by:
      close in interface AutoCloseable
      Specified by:
      close in interface Closeable
      Overrides:
      close in class InflaterInputStream
      Throws:
      IOException - if an I/O error has occurred
      See Also:

    • createZipEntry

      protected ZipEntry createZipEntry(String name)
      Creates a new ZipEntry object for the specified entry name.
      Parameters:
      name - the ZIP file entry name
      Returns:
      the ZipEntry just created