Module java.base
Package java.util.zip

Class DeflaterOutputStream

All Implemented Interfaces:
Closeable, Flushable, AutoCloseable
Direct Known Subclasses:
GZIPOutputStream, ZipOutputStream

public class DeflaterOutputStream extends FilterOutputStream
This class implements an output stream filter for compressing data in the "deflate" compression format. It is also used as the basis for other types of compression filters, such as GZIPOutputStream.
Since:
1.1
See Also:
  • Field Details

    • def

      protected Deflater def
      Compressor for this stream.
    • buf

      protected byte[] buf
      Output buffer for writing compressed data.
  • Constructor Details

    • DeflaterOutputStream

      public DeflaterOutputStream(OutputStream out, Deflater def, int size, boolean syncFlush)
      Creates a new output stream with the specified compressor, buffer size and flush mode.
      Parameters:
      out - the output stream
      def - the compressor ("deflater")
      size - the output buffer size
      syncFlush - if true the flush() method of this instance flushes the compressor with flush mode Deflater.SYNC_FLUSH before flushing the output stream, otherwise only flushes the output stream
      Throws:
      IllegalArgumentException - if size <= 0
      Since:
      1.7
    • DeflaterOutputStream

      public DeflaterOutputStream(OutputStream out, Deflater def, int size)
      Creates a new output stream with the specified compressor and buffer size.

      The new output stream instance is created as if by invoking the 4-argument constructor DeflaterOutputStream(out, def, size, false).

      Parameters:
      out - the output stream
      def - the compressor ("deflater")
      size - the output buffer size
      Throws:
      IllegalArgumentException - if size <= 0
    • DeflaterOutputStream

      public DeflaterOutputStream(OutputStream out, Deflater def, boolean syncFlush)
      Creates a new output stream with the specified compressor, flush mode and a default buffer size.
      Parameters:
      out - the output stream
      def - the compressor ("deflater")
      syncFlush - if true the flush() method of this instance flushes the compressor with flush mode Deflater.SYNC_FLUSH before flushing the output stream, otherwise only flushes the output stream
      Since:
      1.7
    • DeflaterOutputStream

      public DeflaterOutputStream(OutputStream out, Deflater def)
      Creates a new output stream with the specified compressor and a default buffer size.

      The new output stream instance is created as if by invoking the 3-argument constructor DeflaterOutputStream(out, def, false).

      Parameters:
      out - the output stream
      def - the compressor ("deflater")
    • DeflaterOutputStream

      public DeflaterOutputStream(OutputStream out, boolean syncFlush)
      Creates a new output stream with a default compressor, a default buffer size and the specified flush mode.
      Parameters:
      out - the output stream
      syncFlush - if true the flush() method of this instance flushes the compressor with flush mode Deflater.SYNC_FLUSH before flushing the output stream, otherwise only flushes the output stream
      Since:
      1.7
    • DeflaterOutputStream

      public DeflaterOutputStream(OutputStream out)
      Creates a new output stream with a default compressor and buffer size.

      The new output stream instance is created as if by invoking the 2-argument constructor DeflaterOutputStream(out, false).

      Parameters:
      out - the output stream
  • Method Details

    • write

      public void write(int b) throws IOException
      Writes a byte to the compressed output stream. This method will block until the byte can be written.
      Overrides:
      write in class FilterOutputStream
      Parameters:
      b - the byte to be written
      Throws:
      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 compressed output stream. This method will block until all the bytes are written.
      Overrides:
      write in class FilterOutputStream
      Parameters:
      b - the data to be written
      off - the start offset of the data
      len - the length of the data
      Throws:
      IOException - if an I/O error has occurred
      See Also:
    • finish

      public void finish() throws IOException
      Finishes writing compressed data to the output stream without closing the underlying stream. Use this method when applying multiple filters in succession to the same output stream.
      Throws:
      IOException - if an I/O error has occurred
    • close

      public void close() throws IOException
      Writes remaining compressed data to the output stream and closes the underlying stream.
      Specified by:
      close in interface AutoCloseable
      Specified by:
      close in interface Closeable
      Overrides:
      close in class FilterOutputStream
      Throws:
      IOException - if an I/O error has occurred
      See Also:
    • deflate

      protected void deflate() throws IOException
      Writes next block of compressed data to the output stream.
      Throws:
      IOException - if an I/O error has occurred
    • flush

      public void flush() throws IOException
      Flushes the compressed output stream. If syncFlush is true when this compressed output stream is constructed, this method first flushes the underlying compressor with the flush mode Deflater.SYNC_FLUSH to force all pending data to be flushed out to the output stream and then flushes the output stream. Otherwise this method only flushes the output stream without flushing the compressor.
      Specified by:
      flush in interface Flushable
      Overrides:
      flush in class FilterOutputStream
      Throws:
      IOException - if an I/O error has occurred
      Since:
      1.7
      See Also: