Marks the current position in this input stream.

  Marks the current position in this input stream. A subsequent call to the reset method repositions this stream at the last marked position so that subsequent reads re-read the same bytes.

The readlimit arguments tells this input stream to allow that many bytes to be read before the mark position gets invalidated.

The general contract of mark is that, if the method markSupported returns true, the stream somehow remembers all the bytes read after the call to mark and stands ready to supply those same bytes again if and whenever the method reset is called. However, the stream is not required to remember any data at all if more than readlimit bytes are read from the stream before reset is called.

Marking a closed stream should not have any effect on the stream.

The mark method of InputStream does nothing.
Parameters:
- readlimit - the maximum limit of bytes that can be read before the mark position becomes invalid.
See Also: InputStream.reset(),

  Tests if this input stream supports the mark and reset methods.

  Tests if this input stream supports the mark and
reset methods. Whether or not mark and
reset are supported is an invariant property of a
particular input stream instance. The markSupported method
of InputStream returns false.
Returns: true if this stream instance supports the mark and reset methods; false otherwise.
See Also: InputStream.mark(int), InputStream.reset(),

  Reads some number of bytes from the input stream and stores them into the buffer array b.

  Reads some number of bytes from the input stream and stores them into the buffer array b. The number of bytes actually read is returned as an integer. This method blocks until input data is available, end of file is detected, or an exception is thrown.

If the length of b is zero, then no bytes are read and 0 is returned; otherwise, there is an attempt to read at least one byte. If no byte is available because the stream is at the end of the file, the value -1 is returned; otherwise, at least one byte is read and stored into b.

The first byte read is stored into element b[0], the next one into b[1], and so on. The number of bytes read is, at most, equal to the length of b. Let k be the number of bytes actually read; these bytes will be stored in elements b[0] through b[k-1], leaving elements b[k] through b[b.length-1] unaffected.

The read(b) method for class InputStream has the same effect as:

 read(b, 0, b.length) 

Returns: the total number of bytes read into the buffer, or -1 is there is no more data because the end of the stream has been reached.
Parameters:
- b - the buffer into which the data is read.
Throws:
- IOException - If the first byte cannot be read for any reason other than the end of the file, if the input stream has been closed, or if some other I/O error occurs.
- NullPointerException - if b is null.
See Also: InputStream.read(byte[], int, int),

  Repositions this stream to the position at the time the mark method was last called on this input stream.

  Repositions this stream to the position at the time the mark method was last called on this input stream.

The general contract of reset is:

• If the method markSupported returns true, then:
  • If the method mark has not been called since the stream was created, or the number of bytes read from the stream since mark was last called is larger than the argument to mark at that last call, then an IOException might be thrown.
  • If such an IOException is not thrown, then the stream is reset to a state such that all the bytes read since the most recent call to mark (or since the start of the file, if mark has not been called) will be resupplied to subsequent callers of the read method, followed by any bytes that otherwise would have been the next input data as of the time of the call to reset.
• If the method markSupported returns false, then:
  • The call to reset may throw an IOException.
  • If an IOException is not thrown, then the stream is reset to a fixed state that depends on the particular type of the input stream and how it was created. The bytes that will be supplied to subsequent callers of the read method depend on the particular type of the input stream.

The method reset for class InputStream does nothing except throw an IOException.
Throws:
- IOException - if this stream has not been marked or if the mark has been invalidated.
See Also: InputStream.mark(int), IOException,

  Skips over and discards n bytes of data from this input stream.

  Skips over and discards n bytes of data from this input stream. The skip method may, for a variety of reasons, end up skipping over some smaller number of bytes, possibly 0. This may result from any of a number of conditions; reaching end of file before n bytes have been skipped is only one possibility. The actual number of bytes skipped is returned. If n is negative, no bytes are skipped.

The skip method of this class creates a byte array and then repeatedly reads into it until n bytes have been read or the end of the stream has been reached. Subclasses are encouraged to provide a more efficient implementation of this method. For instance, the implementation may depend on the ability to seek.
Returns: the actual number of bytes skipped.
Parameters:
- n - the number of bytes to be skipped.
Throws:
- IOException - if the stream does not support seek, or if some other I/O error occurs.