Class InflaterInputStream

java.lang.Object
java.io.InputStream
java.io.FilterInputStream
java.util.zip.InflaterInputStream
All Implemented Interfaces:
Closeable,AutoCloseable
Direct Known Subclasses:
GZIPInputStream,ZipInputStream
public classInflaterInputStreamextendsFilterInputStream
This class implements a stream filter for uncompressing data in the "deflate" compression format. It is also used as the basis for other decompression filters, such as GZIPInputStream.

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

Since:
1.1
See Also:

  • Field Details

    • inf

      protected Inflater inf
      Decompressor for this stream.

    • buf

      protected byte[] buf
      Input buffer for decompression.

    • len

      protected int len
      The total number of bytes read into the input buffer.

  • Constructor Details

    • InflaterInputStream

      public InflaterInputStream(InputStream in,Inflater inf, int size)
      Creates a new input stream with the specified decompressor and buffer size.
      Parameters:
      in - the input stream
      inf - the decompressor ("inflater")
      size - the input buffer size
      Throws:
      IllegalArgumentException - ifsize <= 0

    • InflaterInputStream

      public InflaterInputStream(InputStream in,Inflater inf)
      Creates a new input stream with the specified decompressor and a default buffer size.
      Parameters:
      in - the input stream
      inf - the decompressor ("inflater")

    • InflaterInputStream

      public InflaterInputStream(InputStream in)
      Creates a new input stream with a default decompressor and buffer size.
      Parameters:
      in - the input stream

  • Method Details

    • read

      public int read() throwsIOException
      Reads a byte of uncompressed data. This method will block until enough input is available for decompression.
      Overrides:
      read in class FilterInputStream
      Returns:
      the byte read, or -1 if end of compressed input is reached
      Throws:
      IOException - if an I/O error has occurred
      See Also:

    • read

      public int read(byte[] b, int off, int len) throwsIOException
      Reads uncompressed data into an array of bytes, returning the number of inflated bytes. Iflen is not zero, the method will block until some input can be decompressed; otherwise, no bytes are read and0 is returned.

      If this method returns a nonzero integern thenbuf[off] throughbuf[off+n-1] contain the uncompressed data. The content of elementsbuf[off+n] throughbuf[off+len-1] is undefined, contrary to the specification of theInputStream superclass, so an implementation is free to modify these elements during the inflate operation. If this method returns-1 or throws an exception then the content ofbuf[off] throughbuf[off+len -1] is undefined.

      Overrides:
      read in class FilterInputStream
      Parameters:
      b - the buffer into which the data is read
      off - the start offset in the destination arrayb
      len - the maximum number of bytes read
      Returns:
      the actual number of bytes inflated, or -1 if the end of the compressed input is reached or a preset dictionary is needed
      Throws:
      IndexOutOfBoundsException - Ifoff is negative,len is negative, orlen is greater thanb.length - off
      ZipException - if a ZIP format error has occurred
      IOException - if an I/O error has occurred
      See Also:

    • available

      public int available() throwsIOException
      Returns 0 after EOF has been reached, 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 FilterInputStream
      Returns:
      1 before EOF and 0 after EOF.
      Throws:
      IOException - if an I/O error occurs.

    • skip

      public long skip(long n) throwsIOException
      Skips specified number of bytes of uncompressed data. This method may block until the specified number of bytes are skipped or end of stream is reached.
      Overrides:
      skip in class FilterInputStream
      Implementation Note:
      This method skips at mostInteger.MAX_VALUE bytes.
      Parameters:
      n - the number of bytes to skip. Ifn is zero then no bytes are skipped.
      Returns:
      the actual number of bytes skipped, which might be zero
      Throws:
      IOException - if an I/O error occurs or if this stream is already closed
      IllegalArgumentException - ifn < 0
      See Also:

    • close

      public void close() throwsIOException
      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 FilterInputStream
      Throws:
      IOException - if an I/O error has occurred
      See Also:

    • fill

      protected void fill() throwsIOException
      Fills input buffer with more data to decompress.
      Implementation Requirements:
      This method will read up tobuf.length bytes into the input buffer,buf, starting at element0. Thelen field will be set to the number of bytes read.
      Throws:
      IOException - if an I/O error has occurred
      EOFException - if the end of input stream has been reached unexpectedly

    • markSupported

      public boolean markSupported()
      Tests if this input stream supports themark andreset methods. ThemarkSupported method ofInflaterInputStream returnsfalse.
      Overrides:
      markSupported in class FilterInputStream
      Returns:
      aboolean indicating if this stream type supports themark andreset methods.
      See Also:

    • mark

      public void mark(int readlimit)
      Marks the current position in this input stream.
      Overrides:
      mark in class FilterInputStream
      Implementation Requirements:
      Themark method ofInflaterInputStream does nothing.
      Parameters:
      readlimit - the maximum limit of bytes that can be read before the mark position becomes invalid.
      See Also:

    • reset

      public void reset() throwsIOException
      Repositions this stream to the position at the time themark method was last called on this input stream.
      Overrides:
      reset in class FilterInputStream
      Implementation Requirements:
      The methodreset for classInflaterInputStream does nothing except throw anIOException.
      Throws:
      IOException - if this method is invoked.
      See Also: