com.adobe.acrobat.bytearray
Class ByteRangeInputStream

java.lang.Object
  |
  +--java.io.InputStream
        |
        +--com.adobe.acrobat.bytearray.ByteRangeInputStream

public class ByteRangeInputStream

extends java.io.InputStream

InputStream subclass that, given a ContiguousByteRange and an InputStream, streams only those bytes from the given InputStream whose offsets are delimited by the ContiguousByteRange.

Version:

1.0 9 April 1997 Copyright (c) 1997, Adobe Systems Inc., All Rights Reserved.

Constructor Summary

ByteRangeInputStream(java.io.InputStream stm, ContiguousByteRange br)
Create a new ByteRangeInputStream which provides only the bytes from the given InputStream at offsets contained in the given ContiguousByteRange.

Method Summary

int	available() Return the number of bytes available on this ByteRangeInputStream for the next read to return without blocking.
void	mark(int readlimit) Mark the current position in this ByteRangeInputStream
boolean	markSupported() Return whether or not marking is supported on this ByteRangeInputStream.
int	read() Read the next byte in the substream whose offset appears in this ByteRangeInputStream's associated ContiguousByteRange.
int	read(byte[] b, int off, int len) Read the next len bytes into the byte-buffer b starting at b[off] and return the number of bytes actually read.
void	reset() Reset this ByteRangeInputStream back to wherever it was the last time mark was called.
long	skip(long n) Skip at most n bytes in this ByteRangeInputStream.

Methods inherited from class java.io.InputStream

close, read

Methods inherited from class java.lang.Object

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

Constructor Detail

ByteRangeInputStream

public ByteRangeInputStream(java.io.InputStream stm,
                            ContiguousByteRange br)

Create a new ByteRangeInputStream which provides only the bytes from the given InputStream at offsets contained in the given ContiguousByteRange.

Parameters:

stm - the InputStream, a subset of whose bytes will be provided by this ByteRangeInputStream

br - the ContiguousByteRange enumerating which bytes are to be read and which are to be skipped

Method Detail

available

public int available()
              throws java.io.IOException

Return the number of bytes available on this ByteRangeInputStream for the next read to return without blocking.

Returns:

the number of available bytes

Throws:

java.io.IOException - Arbitrary IOExceptions may be thrown

Overrides:

available in class java.io.InputStream

mark

public void mark(int readlimit)

Mark the current position in this ByteRangeInputStream

Parameters:

readLimit - the maximum number of bytes that will be read before the next reset

Overrides:

mark in class java.io.InputStream

See Also:

reset, markSupported

markSupported

public boolean markSupported()

Return whether or not marking is supported on this ByteRangeInputStream. If the sub-InputStream from which this ByteRangeInputStream reads its bytes supports marking, so does this ByteRangeInputStream.

Returns:

true if mark is supported

Overrides:

markSupported in class java.io.InputStream

See Also:

mark, reset

read

public int read()
         throws java.io.IOException

Read the next byte in the substream whose offset appears in this ByteRangeInputStream's associated ContiguousByteRange.

Returns:

the next byte in this stream, or -1 if at EOF

Throws:

java.io.IOException - arbitrary IOExceptions may be thrown

Overrides:

read in class java.io.InputStream

read

public int read(byte[] b,
                int off,
                int len)
         throws java.io.IOException

Read the next len bytes into the byte-buffer b starting at b[off] and return the number of bytes actually read.

Parameters:

b - the buffer into which to read the bytes

off - the offset in b at which to start writing the bytes

len - the maximum number of bytes to write

Returns:

the actual number of bytes written, or -1 if at EOF

Throws:

java.io.IOException - arbitrary IOExceptions may be thrown

Overrides:

read in class java.io.InputStream

reset

public void reset()
           throws java.io.IOException

Reset this ByteRangeInputStream back to wherever it was the last time mark was called.

Throws:

java.io.IOException - arbitrary IOExceptions may be thrown

Overrides:

reset in class java.io.InputStream

See Also:

mark, markSupported

skip

public long skip(long n)
          throws java.io.IOException

Skip at most n bytes in this ByteRangeInputStream.

Parameters:

n - the number of bytes to skip

Returns:

the number of bytes that were actually skipped

Throws:

java.io.IOException - arbitrary IOExceptions may be thrown

Overrides:

skip in class java.io.InputStream