Class ZipFile

java.lang.Object
java.util.zip.ZipFile
All Implemented Interfaces:
Closeable, AutoCloseable
Direct Known Subclasses:
JarFile
public class ZipFile extends Object implements Closeable
This class is used to read entries from a ZIP file.

Unless otherwise noted, passing a null argument to a constructor or method in this class will cause a NullPointerException to be thrown.

API Note:
To release resources used by this ZipFile, the close() method should be called explicitly or by try-with-resources. Subclasses are responsible for the cleanup of resources acquired by the subclass. Subclasses that override Object.finalize() in order to perform cleanup should be modified to use alternative cleanup mechanisms such as Cleaner and remove the overriding finalize method.
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.
    static final int
    OPEN_DELETE
    Mode flag to open a ZIP file and mark it for deletion.
    static final int
    OPEN_READ
    Mode flag to open a ZIP file for reading.

  • Constructor Summary

    Constructors
    Constructor
    Description
    ZipFile(File file)
    Opens a ZIP file for reading given the specified File object.
    ZipFile(File file, int mode)
    Opens a new ZipFile to read from the specified File object in the specified mode.
    ZipFile(File file, int mode, Charset charset)
    Opens a new ZipFile to read from the specified File object in the specified mode.
    ZipFile(File file, Charset charset)
    Opens a ZIP file for reading given the specified File object.
    ZipFile(String name)
    Opens a ZIP file for reading.
    ZipFile(String name, Charset charset)
    Opens a ZIP file for reading.

  • Method Summary

    Modifier and Type
    Method
    Description
    void
    close()
    Closes the ZIP file.
    Enumeration<? extends ZipEntry>
    entries()
    Returns an enumeration of the ZIP file entries.
    String
    getComment()
    Returns the ZIP file comment.
    ZipEntry
    getEntry(String name)
    Returns the ZIP file entry for the specified name, or null if not found.
    InputStream
    getInputStream(ZipEntry entry)
    Returns an input stream for reading the contents of the specified ZIP file entry.
    String
    getName()
    Returns the path name of the ZIP file.
    int
    size()
    Returns the number of entries in the ZIP file.
    Stream<? extends ZipEntry>
    stream()
    Returns an ordered Stream over the ZIP file entries.
    String
    toString()
    Returns a string identifying this ZipFile, for debugging.

    Methods declared in class java.lang.Object

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

  • Field Details

    • OPEN_READ

      public static final int OPEN_READ
      Mode flag to open a ZIP file for reading.
      See Also:

    • OPEN_DELETE

      public static final int OPEN_DELETE
      Mode flag to open a ZIP file and mark it for deletion. The file will be deleted some time between the moment that it is opened and the moment that it is closed, but its contents will remain accessible via the ZipFile object until either the close method is invoked or the virtual machine exits.
      See Also:

    • 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

    • ZipFile

      public ZipFile(String name) throws IOException
      Opens a ZIP file for reading.

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

      Parameters:
      name - the name of the ZIP file
      Throws:
      ZipException - if a ZIP format error has occurred
      IOException - if an I/O error has occurred

    • ZipFile

      public ZipFile(File file, int mode) throws IOException
      Opens a new ZipFile to read from the specified File object in the specified mode. The mode argument must be either OPEN_READ or OPEN_READ | OPEN_DELETE.

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

      Parameters:
      file - the ZIP file to be opened for reading
      mode - the mode in which the file is to be opened
      Throws:
      ZipException - if a ZIP format error has occurred
      IOException - if an I/O error has occurred
      IllegalArgumentException - if the mode argument is invalid
      Since:
      1.3

    • ZipFile

      public ZipFile(File file) throws ZipException, IOException
      Opens a ZIP file for reading given the specified File object.

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

      Parameters:
      file - the ZIP file to be opened for reading
      Throws:
      ZipException - if a ZIP format error has occurred
      IOException - if an I/O error has occurred

    • ZipFile

      public ZipFile(File file, int mode, Charset charset) throws IOException
      Opens a new ZipFile to read from the specified File object in the specified mode. The mode argument must be either OPEN_READ or OPEN_READ | OPEN_DELETE.
      Parameters:
      file - the ZIP file to be opened for reading
      mode - the mode in which the file is to be opened
      charset - the charset to be used to decode the ZIP entry name and comment that are not encoded by using UTF-8 encoding (indicated by entry's general purpose flag).
      Throws:
      ZipException - if a ZIP format error has occurred
      IOException - if an I/O error has occurred
      IllegalArgumentException - if the mode argument is invalid
      Since:
      1.7

    • ZipFile

      public ZipFile(String name, Charset charset) throws IOException
      Opens a ZIP file for reading.
      Parameters:
      name - the name of the ZIP file
      charset - the charset to be used to decode the ZIP entry name and comment that are not encoded by using UTF-8 encoding (indicated by entry's general purpose flag).
      Throws:
      ZipException - if a ZIP format error has occurred
      IOException - if an I/O error has occurred
      Since:
      1.7

    • ZipFile

      public ZipFile(File file, Charset charset) throws IOException
      Opens a ZIP file for reading given the specified File object.
      Parameters:
      file - the ZIP file to be opened for reading
      charset - The charset to be used to decode the ZIP entry name and comment (ignored if the language encoding bit of the ZIP entry's general purpose bit flag is set).
      Throws:
      ZipException - if a ZIP format error has occurred
      IOException - if an I/O error has occurred
      Since:
      1.7

  • Method Details

    • getComment

      public String getComment()
      Returns the ZIP file comment. If a comment does not exist or an error is encountered decoding the comment using the charset specified when opening the ZIP file, then null is returned.
      Returns:
      the comment string for the ZIP file, or null if none
      Throws:
      IllegalStateException - if the ZIP file has been closed
      Since:
      1.7

    • getEntry

      public ZipEntry getEntry(String name)
      Returns the ZIP file entry for the specified name, or null if not found.
      Parameters:
      name - the name of the entry
      Returns:
      the ZIP file entry, or null if not found
      Throws:
      IllegalStateException - if the ZIP file has been closed

    • getInputStream

      public InputStream getInputStream(ZipEntry entry) throws IOException
      Returns an input stream for reading the contents of the specified ZIP file entry.

      Closing this ZIP file will, in turn, close all input streams that have been returned by invocations of this method.

      API Note:
      The InputStream returned by this method can wrap an InflaterInputStream, whose read(byte[], int, int) method can modify any element of the output buffer.
      Parameters:
      entry - the ZIP file entry
      Returns:
      the input stream for reading the contents of the specified ZIP file entry or null if the ZIP file entry does not exist within the ZIP file.
      Throws:
      ZipException - if a ZIP format error has occurred
      IOException - if an I/O error has occurred
      IllegalStateException - if the ZIP file has been closed

    • getName

      public String getName()
      Returns the path name of the ZIP file.
      Returns:
      the path name of the ZIP file

    • toString

      public String toString()
      Returns a string identifying this ZipFile, for debugging.
      Overrides:
      toString in class Object
      Returns:
      a string identifying this ZipFile, for debugging

    • entries

      public Enumeration<? extends ZipEntry> entries()
      Returns an enumeration of the ZIP file entries.
      Returns:
      an enumeration of the ZIP file entries
      Throws:
      IllegalStateException - if the ZIP file has been closed

    • stream

      public Stream<? extends ZipEntry> stream()
      Returns an ordered Stream over the ZIP file entries. Entries appear in the Stream in the order they appear in the central directory of the ZIP file.
      Returns:
      an ordered Stream of entries in this ZIP file
      Throws:
      IllegalStateException - if the ZIP file has been closed
      Since:
      1.8

    • size

      public int size()
      Returns the number of entries in the ZIP file.
      Returns:
      the number of entries in the ZIP file
      Throws:
      IllegalStateException - if the ZIP file has been closed

    • close

      public void close() throws IOException
      Closes the ZIP file.

      Closing this ZIP file will close all of the input streams previously returned by invocations of the getInputStream method.

      Specified by:
      close in interface AutoCloseable
      Specified by:
      close in interface Closeable
      Throws:
      IOException - if an I/O error has occurred