1. Description
2. Field Summary
   1. Fields declared in class DeflaterOutputStream
   2. Fields declared in class FilterOutputStream
3. Constructor Summary
4. Method Summary
5. Field Details
   1. STORED
   2. DEFLATED
   3. LOCSIG
   4. EXTSIG
   5. CENSIG
   6. ENDSIG
   7. LOCHDR
   8. EXTHDR
   9. CENHDR
   10. ENDHDR
   11. LOCVER
   12. LOCFLG
   13. LOCHOW
   14. LOCTIM
   15. LOCCRC
   16. LOCSIZ
   17. LOCLEN
   18. LOCNAM
   19. LOCEXT
   20. EXTCRC
   21. EXTSIZ
   22. EXTLEN
   23. CENVEM
   24. CENVER
   25. CENFLG
   26. CENHOW
   27. CENTIM
   28. CENCRC
   29. CENSIZ
   30. CENLEN
   31. CENNAM
   32. CENEXT
   33. CENCOM
   34. CENDSK
   35. CENATT
   36. CENATX
   37. CENOFF
   38. ENDSUB
   39. ENDTOT
   40. ENDSIZ
   41. ENDOFF
   42. ENDCOM
6. Constructor Details
   1. ZipOutputStream(OutputStream)
   2. ZipOutputStream(OutputStream, Charset)
7. Method Details
   1. setComment(String)
   2. setMethod(int)
   3. setLevel(int)
   4. putNextEntry(ZipEntry)
   5. closeEntry()
   6. write(byte[], int, int)
   7. finish()
   8. close()

• 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

  DEFLATED

  Compression method for compressed (DEFLATED) entries.

  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

  STORED

  Compression method for uncompressed (STORED) entries.

  Fields declared in class DeflaterOutputStream

  buf, def

  Modifier and Type

  Field

  Description

  protected byte[]

  buf

  Output buffer for writing compressed data.

  protected Deflater

  def

  Compressor for this stream.

  Fields declared in class FilterOutputStream

  out

  Modifier and Type

  Field

  Description

  protected OutputStream

  out

  The underlying output stream to be filtered.

• Constructor Summary

  Constructors
  Constructor

  Description

  ZipOutputStream(OutputStream out)

  Creates a new ZIP output stream.

  ZipOutputStream(OutputStream out, Charset charset)

  Creates a new ZIP output stream.

• Method Summary

  All MethodsInstance MethodsConcrete Methods

  Modifier and Type

  Method

  Description

  void

  close()

  Closes the underlying stream and the stream being filtered after the contents of the ZIP output stream are fully written.

  void

  closeEntry()

  Closes the current ZIP entry and positions the stream for writing the next entry.

  void

  finish()

  Finishes writing the contents of the ZIP output stream without closing the underlying stream.

  void

  putNextEntry(ZipEntry e)

  Begins writing a new ZIP file entry and positions the stream to the start of the entry data.

  void

  setComment(String comment)

  Sets the ZIP file comment.

  void

  setLevel(int level)

  Sets the compression level for subsequent entries which are DEFLATED.

  void

  setMethod(int method)

  Sets the default compression method for subsequent entries.

  void

  write(byte[] b, int off, int len)

  Writes an array of bytes to the current ZIP entry data.

  Methods declared in class DeflaterOutputStream

  deflate, flush, write

  Modifier and Type

  Method

  Description

  protected void

  deflate()

  Writes next block of compressed data to the output stream.

  void

  flush()

  Flushes the compressed output stream.

  void

  write(int b)

  Writes a byte to the compressed output stream.

  Methods declared in class FilterOutputStream

  write

  Modifier and Type

  Method

  Description

  void

  write(byte[] b)

  Writes b.length bytes to this output stream.

  Methods declared in class OutputStream

  nullOutputStream

  Modifier and Type

  Method

  Description

  static OutputStream

  nullOutputStream()

  Returns a new OutputStream which discards all bytes.

  Methods declared in class Object

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

  Modifier and Type

  Method

  Description

  protected Object

  clone()

  Creates and returns a copy of this object.

  boolean

  equals(Object obj)

  Indicates whether some other object is "equal to" this one.

  protected void

  finalize()

  Deprecated, for removal: This API element is subject to removal in a future version.

  Finalization is deprecated and subject to removal in a future release.

  final Class<?>

  getClass()

  Returns the runtime class of this Object.

  int

  hashCode()

  Returns a hash code value for this object.

  final void

  notify()

  Wakes up a single thread that is waiting on this object's monitor.

  final void

  notifyAll()

  Wakes up all threads that are waiting on this object's monitor.

  String

  toString()

  Returns a string representation of the object.

  final void

  wait()

  Causes the current thread to wait until it is awakened, typically by being notified or interrupted.

  final void

  wait(long timeoutMillis)

  Causes the current thread to wait until it is awakened, typically by being notified or interrupted, or until a certain amount of real time has elapsed.

  final void

  wait(long timeoutMillis, int nanos)

  Causes the current thread to wait until it is awakened, typically by being notified or interrupted, or until a certain amount of real time has elapsed.

• Field Details

  • STORED

    public static final int STORED

    Compression method for uncompressed (STORED) entries.

    See Also:

    • Constant Field Values

  • DEFLATED

    public static final int DEFLATED

    Compression method for compressed (DEFLATED) entries.

    See Also:

    • Constant Field Values

  • LOCSIG

    static final long LOCSIG

    Local file (LOC) header signature.

    See Also:

    • Constant Field Values

  • EXTSIG

    static final long EXTSIG

    Extra local (EXT) header signature.

    See Also:

    • Constant Field Values

  • CENSIG

    static final long CENSIG

    Central directory (CEN) header signature.

    See Also:

    • Constant Field Values

  • ENDSIG

    static final long ENDSIG

    End of central directory (END) header signature.

    See Also:

    • Constant Field Values

  • LOCHDR

    static final int LOCHDR

    Local file (LOC) header size in bytes (including signature).

    See Also:

    • Constant Field Values

  • EXTHDR

    static final int EXTHDR

    Extra local (EXT) header size in bytes (including signature).

    See Also:

    • Constant Field Values

  • CENHDR

    static final int CENHDR

    Central directory (CEN) header size in bytes (including signature).

    See Also:

    • Constant Field Values

  • ENDHDR

    static final int ENDHDR

    End of central directory (END) header size in bytes (including signature).

    See Also:

    • Constant Field Values

  • LOCVER

    static final int LOCVER

    Local file (LOC) header version needed to extract field offset.

    See Also:

    • Constant Field Values

  • LOCFLG

    static final int LOCFLG

    Local file (LOC) header general purpose bit flag field offset.

    See Also:

    • Constant Field Values

  • LOCHOW

    static final int LOCHOW

    Local file (LOC) header compression method field offset.

    See Also:

    • Constant Field Values

  • LOCTIM

    static final int LOCTIM

    Local file (LOC) header modification time field offset.

    See Also:

    • Constant Field Values

  • LOCCRC

    static final int LOCCRC

    Local file (LOC) header uncompressed file crc-32 value field offset.

    See Also:

    • Constant Field Values

  • LOCSIZ

    static final int LOCSIZ

    Local file (LOC) header compressed size field offset.

    See Also:

    • Constant Field Values

  • LOCLEN

    static final int LOCLEN

    Local file (LOC) header uncompressed size field offset.

    See Also:

    • Constant Field Values

  • LOCNAM

    static final int LOCNAM

    Local file (LOC) header filename length field offset.

    See Also:

    • Constant Field Values

  • LOCEXT

    static final int LOCEXT

    Local file (LOC) header extra field length field offset.

    See Also:

    • Constant Field Values

  • EXTCRC

    static final int EXTCRC

    Extra local (EXT) header uncompressed file crc-32 value field offset.

    See Also:

    • Constant Field Values

  • EXTSIZ

    static final int EXTSIZ

    Extra local (EXT) header compressed size field offset.

    See Also:

    • Constant Field Values

  • EXTLEN

    static final int EXTLEN

    Extra local (EXT) header uncompressed size field offset.

    See Also:

    • Constant Field Values

  • CENVEM

    static final int CENVEM

    Central directory (CEN) header version made by field offset.

    See Also:

    • Constant Field Values

  • CENVER

    static final int CENVER

    Central directory (CEN) header version needed to extract field offset.

    See Also:

    • Constant Field Values

  • CENFLG

    static final int CENFLG

    Central directory (CEN) header encrypt, decrypt flags field offset.

    See Also:

    • Constant Field Values

  • CENHOW

    static final int CENHOW

    Central directory (CEN) header compression method field offset.

    See Also:

    • Constant Field Values

  • CENTIM

    static final int CENTIM

    Central directory (CEN) header modification time field offset.

    See Also:

    • Constant Field Values

  • CENCRC

    static final int CENCRC

    Central directory (CEN) header uncompressed file crc-32 value field offset.

    See Also:

    • Constant Field Values

  • CENSIZ

    static final int CENSIZ

    Central directory (CEN) header compressed size field offset.

    See Also:

    • Constant Field Values

  • CENLEN

    static final int CENLEN

    Central directory (CEN) header uncompressed size field offset.

    See Also:

    • Constant Field Values

  • CENNAM

    static final int CENNAM

    Central directory (CEN) header filename length field offset.

    See Also:

    • Constant Field Values

  • CENEXT

    static final int CENEXT

    Central directory (CEN) header extra field length field offset.

    See Also:

    • Constant Field Values

  • CENCOM

    static final int CENCOM

    Central directory (CEN) header comment length field offset.

    See Also:

    • Constant Field Values

  • CENDSK

    static final int CENDSK

    Central directory (CEN) header disk number start field offset.

    See Also:

    • Constant Field Values

  • CENATT

    static final int CENATT

    Central directory (CEN) header internal file attributes field offset.

    See Also:

    • Constant Field Values

  • CENATX

    static final int CENATX

    Central directory (CEN) header external file attributes field offset.

    See Also:

    • Constant Field Values

  • CENOFF

    static final int CENOFF

    Central directory (CEN) header LOC header offset field offset.

    See Also:

    • Constant Field Values

  • ENDSUB

    static final int ENDSUB

    End of central directory (END) header number of entries on this disk field offset.

    See Also:

    • Constant Field Values

  • ENDTOT

    static final int ENDTOT

    End of central directory (END) header total number of entries field offset.

    See Also:

    • Constant Field Values

  • ENDSIZ

    static final int ENDSIZ

    End of central directory (END) header central directory size in bytes field offset.

    See Also:

    • Constant Field Values

  • ENDOFF

    static final int ENDOFF

    End of central directory (END) header offset for the first CEN header field offset.

    See Also:

    • Constant Field Values

  • ENDCOM

    static final int ENDCOM

    End of central directory (END) header ZIP file comment length field offset.

    See Also:

    • Constant Field Values

• Constructor Details

  • ZipOutputStream

    public ZipOutputStream(OutputStream out)

    Creates a new ZIP output stream.

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

    Parameters: out - the actual output stream

  • ZipOutputStream

    public ZipOutputStream(OutputStream out, Charset charset)

    Creates a new ZIP output stream.

    Parameters: out - the actual output stream charset - the charset to be used to encode the entry names and comments Since: 1.7

• Method Details

  • setComment

    public void setComment(String comment)

    Sets the ZIP file comment.

    Parameters: comment - the comment string Throws: IllegalArgumentException - if the length of the specified ZIP file comment is greater than 0xFFFF bytes

  • setMethod

    public void setMethod(int method)

    Sets the default compression method for subsequent entries. This default will be used whenever the compression method is not specified for an individual ZIP file entry, and is initially set to DEFLATED.

    Parameters: method - the default compression method Throws: IllegalArgumentException - if the specified compression method is invalid

  • setLevel

    public void setLevel(int level)

    Sets the compression level for subsequent entries which are DEFLATED. The default setting is DEFAULT_COMPRESSION.

    Parameters: level - the compression level (0-9) Throws: IllegalArgumentException - if the compression level is invalid

  • putNextEntry

    public void putNextEntry(ZipEntry e) throws IOException

    Begins writing a new ZIP file entry and positions the stream to the start of the entry data. Closes the current entry if still active.

    The default compression method will be used if no compression method was specified for the entry. When writing a compressed (DEFLATED) entry, and the compressed size has not been explicitly set with the ZipEntry.setCompressedSize(long) method, then the compressed size will be set to the actual compressed size after deflation.

    The current time will be used if the entry has no set modification time.

    API Note: When writing a directory entry, the STORED compression method should be used and the size and CRC-32 values should be set to 0:

    Copy ZipEntry e = new ZipEntry(entryName); if (e.isDirectory()) { e.setMethod(ZipEntry.STORED); e.setSize(0); e.setCrc(0); } stream.putNextEntry(e);

    This allows optimal performance when processing directory entries. Parameters: e - the ZIP entry to be written Throws: ZipException - if a ZIP format 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 writing the next entry.

    Throws: ZipException - if a ZIP format error has occurred IOException - if an I/O error has occurred

  • write

    public void write(byte[] b, int off, int len) throws IOException

    Writes an array of bytes to the current ZIP entry data. This method will block until all the bytes are written.

    Overrides: write in class DeflaterOutputStream Parameters: b - the data to be written off - the start offset in the data len - the number of bytes that are written Throws: ZipException - if a ZIP file error has occurred IOException - if an I/O error has occurred See Also:

    • FilterOutputStream.write(int)

  • finish

    public void finish() throws IOException

    Finishes writing the contents of the ZIP output stream without closing the underlying stream. Use this method when applying multiple filters in succession to the same output stream.

    A ZipException will be thrown if the combined length, after encoding, of the entry name, the extra field data, the entry comment and CEN Header size, exceeds 65,535 bytes.

    Overrides: finish in class DeflaterOutputStream Throws: ZipException - if a ZIP file error has occurred IOException - if an I/O exception has occurred

  • close

    public void close() throws IOException

    Closes the underlying stream and the stream being filtered after the contents of the ZIP output stream are fully written.

    Specified by: close in interface AutoCloseable Specified by: close in interface Closeable Overrides: close in class DeflaterOutputStream Throws: ZipException - if a ZIP file error has occurred IOException - if an I/O error has occurred See Also:

    • FilterOutputStream.flush()
    • FilterOutputStream.out

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