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	/*
	* Copyright (c) 1994, 2021, Oracle and/or its affiliates. All rights reserved.
	* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
	*
	* This code is free software; you can redistribute it and/or modify it
	* under the terms of the GNU General Public License version 2 only, as
	* published by the Free Software Foundation. Oracle designates this
	* particular file as subject to the "Classpath" exception as provided
	* by Oracle in the LICENSE file that accompanied this code.
	*
	* This code is distributed in the hope that it will be useful, but WITHOUT
	* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
	* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
	* version 2 for more details (a copy is included in the LICENSE file that
	* accompanied this code).
	*
	* You should have received a copy of the GNU General Public License version
	* 2 along with this work; if not, write to the Free Software Foundation,
	* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
	*
	* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
	* or visit www.oracle.com if you need additional information or have any
	* questions.
	*/

	package java.io;

	import java.util.ArrayList;
	import java.util.Arrays;
	import java.util.List;
	import java.util.Objects;

	/**
	* This abstract class is the superclass of all classes representing
	* an input stream of bytes.
	*
	* <p> Applications that need to define a subclass of {@code InputStream}
	* must always provide a method that returns the next byte of input.
	*
	* @author Arthur van Hoff
	* @see java.io.BufferedInputStream
	* @see java.io.ByteArrayInputStream
	* @see java.io.DataInputStream
	* @see java.io.FilterInputStream
	* @see java.io.InputStream#read()
	* @see java.io.OutputStream
	* @see java.io.PushbackInputStream
	* @since 1.0
	*/
	public abstract class InputStream implements Closeable {

	// MAX_SKIP_BUFFER_SIZE is used to determine the maximum buffer size to
	// use when skipping.
	private static final int MAX_SKIP_BUFFER_SIZE = 2048;

	private static final int DEFAULT_BUFFER_SIZE = 8192;

	/**
	* Constructor for subclasses to call.
	*/
	public InputStream() {}

	/**
	* Returns a new {@code InputStream} that reads no bytes. The returned
	* stream is initially open. The stream is closed by calling the
	* {@code close()} method. Subsequent calls to {@code close()} have no
	* effect.
	*
	* <p> While the stream is open, the {@code available()}, {@code read()},
	* {@code read(byte[])}, {@code read(byte[], int, int)},
	* {@code readAllBytes()}, {@code readNBytes(byte[], int, int)},
	* {@code readNBytes(int)}, {@code skip(long)}, {@code skipNBytes(long)},
	* and {@code transferTo()} methods all behave as if end of stream has been
	* reached. After the stream has been closed, these methods all throw
	* {@code IOException}.
	*
	* <p> The {@code markSupported()} method returns {@code false}. The
	* {@code mark()} method does nothing, and the {@code reset()} method
	* throws {@code IOException}.
	*
	* @return an {@code InputStream} which contains no bytes
	*
	* @since 11
	*/
	public static InputStream nullInputStream() {
	return new InputStream() {
	private volatile boolean closed;

	private void ensureOpen() throws IOException {
	if (closed) {
	throw new IOException("Stream closed");
	}
	}

	@Override
	public int available () throws IOException {
	ensureOpen();
	return 0;
	}

	@Override
	public int read() throws IOException {
	ensureOpen();
	return -1;
	}

	@Override
	public int read(byte[] b, int off, int len) throws IOException {
	Objects.checkFromIndexSize(off, len, b.length);
	if (len == 0) {
	return 0;
	}
	ensureOpen();
	return -1;
	}

	@Override
	public byte[] readAllBytes() throws IOException {
	ensureOpen();
	return new byte[0];
	}

	@Override
	public int readNBytes(byte[] b, int off, int len)
	throws IOException {
	Objects.checkFromIndexSize(off, len, b.length);
	ensureOpen();
	return 0;
	}

	@Override
	public byte[] readNBytes(int len) throws IOException {
	if (len < 0) {
	throw new IllegalArgumentException("len < 0");
	}
	ensureOpen();
	return new byte[0];
	}

	@Override
	public long skip(long n) throws IOException {
	ensureOpen();
	return 0L;
	}

	@Override
	public void skipNBytes(long n) throws IOException {
	ensureOpen();
	if (n > 0) {
	throw new EOFException();
	}
	}

	@Override
	public long transferTo(OutputStream out) throws IOException {
	Objects.requireNonNull(out);
	ensureOpen();
	return 0L;
	}

	@Override
	public void close() throws IOException {
	closed = true;
	}
	};
	}

	/**
	* Reads the next byte of data from the input stream. The value byte is
	* returned as an {@code int} in the range {@code 0} to
	* {@code 255}. If no byte is available because the end of the stream
	* has been reached, the value {@code -1} is returned. This method
	* blocks until input data is available, the end of the stream is detected,
	* or an exception is thrown.
	*
	* <p> A subclass must provide an implementation of this method.
	*
	* @return the next byte of data, or {@code -1} if the end of the
	* stream is reached.
	* @throws IOException if an I/O error occurs.
	*/
	public abstract int read() throws IOException;

	/**
	* Reads some number of bytes from the input stream and stores them into
	* the buffer array {@code 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.
	*
	* <p> If the length of {@code b} is zero, then no bytes are read and
	* {@code 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 {@code -1} is returned; otherwise, at
	* least one byte is read and stored into {@code b}.
	*
	* <p> The first byte read is stored into element {@code b[0]}, the
	* next one into {@code b[1]}, and so on. The number of bytes read is,
	* at most, equal to the length of {@code b}. Let <i>k</i> be the
	* number of bytes actually read; these bytes will be stored in elements
	* {@code b[0]} through {@code b[}<i>k</i>{@code -1]},
	* leaving elements {@code b[}<i>k</i>{@code ]} through
	* {@code b[b.length-1]} unaffected.
	*
	* <p> The {@code read(b)} method for class {@code InputStream}
	* has the same effect as: <pre>{@code read(b, 0, b.length) }</pre>
	*
	* @param b the buffer into which the data is read.
	* @return the total number of bytes read into the buffer, or
	* {@code -1} if there is no more data because the end of
	* the stream has been reached.
	* @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.
	* @throws NullPointerException if {@code b} is {@code null}.
	* @see java.io.InputStream#read(byte[], int, int)
	*/
	public int read(byte b[]) throws IOException {
	return read(b, 0, b.length);
	}

	/**
	* Reads up to {@code len} bytes of data from the input stream into
	* an array of bytes. An attempt is made to read as many as
	* {@code len} bytes, but a smaller number may be read.
	* The number of bytes actually read is returned as an integer.
	*
	* <p> This method blocks until input data is available, end of file is
	* detected, or an exception is thrown.
	*
	* <p> If {@code len} is zero, then no bytes are read and
	* {@code 0} is returned; otherwise, there is an attempt to read at
	* least one byte. If no byte is available because the stream is at end of
	* file, the value {@code -1} is returned; otherwise, at least one
	* byte is read and stored into {@code b}.
	*
	* <p> The first byte read is stored into element {@code b[off]}, the
	* next one into {@code b[off+1]}, and so on. The number of bytes read
	* is, at most, equal to {@code len}. Let <i>k</i> be the number of
	* bytes actually read; these bytes will be stored in elements
	* {@code b[off]} through {@code b[off+}<i>k</i>{@code -1]},
	* leaving elements {@code b[off+}<i>k</i>{@code ]} through
	* {@code b[off+len-1]} unaffected.
	*
	* <p> In every case, elements {@code b[0]} through
	* {@code b[off-1]} and elements {@code b[off+len]} through
	* {@code b[b.length-1]} are unaffected.
	*
	* <p> The {@code read(b, off, len)} method
	* for class {@code InputStream} simply calls the method
	* {@code read()} repeatedly. If the first such call results in an
	* {@code IOException}, that exception is returned from the call to
	* the {@code read(b,} {@code off,} {@code len)} method. If
	* any subsequent call to {@code read()} results in a
	* {@code IOException}, the exception is caught and treated as if it
	* were end of file; the bytes read up to that point are stored into
	* {@code b} and the number of bytes read before the exception
	* occurred is returned. The default implementation of this method blocks
	* until the requested amount of input data {@code len} has been read,
	* end of file is detected, or an exception is thrown. Subclasses are
	* encouraged to provide a more efficient implementation of this method.
	*
	* @param b the buffer into which the data is read.
	* @param off the start offset in array {@code b}
	* at which the data is written.
	* @param len the maximum number of bytes to read.
	* @return the total number of bytes read into the buffer, or
	* {@code -1} if there is no more data because the end of
	* the stream has been reached.
	* @throws IOException If the first byte cannot be read for any reason
	* other than end of file, or if the input stream has been closed,
	* or if some other I/O error occurs.
	* @throws NullPointerException If {@code b} is {@code null}.
	* @throws IndexOutOfBoundsException If {@code off} is negative,
	* {@code len} is negative, or {@code len} is greater than
	* {@code b.length - off}
	* @see java.io.InputStream#read()
	*/
	public int read(byte b[], int off, int len) throws IOException {
	Objects.checkFromIndexSize(off, len, b.length);
	if (len == 0) {
	return 0;
	}

	int c = read();
	if (c == -1) {
	return -1;
	}
	b[off] = (byte)c;

	int i = 1;
	try {
	for (; i < len ; i++) {
	c = read();
	if (c == -1) {
	break;
	}
	b[off + i] = (byte)c;
	}
	} catch (IOException ee) {
	}
	return i;
	}

	/**
	* The maximum size of array to allocate.
	* Some VMs reserve some header words in an array.
	* Attempts to allocate larger arrays may result in
	* OutOfMemoryError: Requested array size exceeds VM limit
	*/
	private static final int MAX_BUFFER_SIZE = Integer.MAX_VALUE - 8;

	/**
	* Reads all remaining bytes from the input stream. This method blocks until
	* all remaining bytes have been read and end of stream is detected, or an
	* exception is thrown. This method does not close the input stream.
	*
	* <p> When this stream reaches end of stream, further invocations of this
	* method will return an empty byte array.
	*
	* <p> Note that this method is intended for simple cases where it is
	* convenient to read all bytes into a byte array. It is not intended for
	* reading input streams with large amounts of data.
	*
	* <p> The behavior for the case where the input stream is <i>asynchronously
	* closed</i>, or the thread interrupted during the read, is highly input
	* stream specific, and therefore not specified.
	*
	* <p> If an I/O error occurs reading from the input stream, then it may do
	* so after some, but not all, bytes have been read. Consequently the input
	* stream may not be at end of stream and may be in an inconsistent state.
	* It is strongly recommended that the stream be promptly closed if an I/O
	* error occurs.
	*
	* @implSpec
	* This method invokes {@link #readNBytes(int)} with a length of
	* {@link Integer#MAX_VALUE}.
	*
	* @return a byte array containing the bytes read from this input stream
	* @throws IOException if an I/O error occurs
	* @throws OutOfMemoryError if an array of the required size cannot be
	* allocated.
	*
	* @since 9
	*/
	public byte[] readAllBytes() throws IOException {
	return readNBytes(Integer.MAX_VALUE);
	}

	/**
	* Reads up to a specified number of bytes from the input stream. This
	* method blocks until the requested number of bytes has been read, end
	* of stream is detected, or an exception is thrown. This method does not
	* close the input stream.
	*
	* <p> The length of the returned array equals the number of bytes read
	* from the stream. If {@code len} is zero, then no bytes are read and
	* an empty byte array is returned. Otherwise, up to {@code len} bytes
	* are read from the stream. Fewer than {@code len} bytes may be read if
	* end of stream is encountered.
	*
	* <p> When this stream reaches end of stream, further invocations of this
	* method will return an empty byte array.
	*
	* <p> Note that this method is intended for simple cases where it is
	* convenient to read the specified number of bytes into a byte array. The
	* total amount of memory allocated by this method is proportional to the
	* number of bytes read from the stream which is bounded by {@code len}.
	* Therefore, the method may be safely called with very large values of
	* {@code len} provided sufficient memory is available.
	*
	* <p> The behavior for the case where the input stream is <i>asynchronously
	* closed</i>, or the thread interrupted during the read, is highly input
	* stream specific, and therefore not specified.
	*
	* <p> If an I/O error occurs reading from the input stream, then it may do
	* so after some, but not all, bytes have been read. Consequently the input
	* stream may not be at end of stream and may be in an inconsistent state.
	* It is strongly recommended that the stream be promptly closed if an I/O
	* error occurs.
	*
	* @implNote
	* The number of bytes allocated to read data from this stream and return
	* the result is bounded by {@code 2*(long)len}, inclusive.
	*
	* @param len the maximum number of bytes to read
	* @return a byte array containing the bytes read from this input stream
	* @throws IllegalArgumentException if {@code length} is negative
	* @throws IOException if an I/O error occurs
	* @throws OutOfMemoryError if an array of the required size cannot be
	* allocated.
	*
	* @since 11
	*/
	public byte[] readNBytes(int len) throws IOException {
	if (len < 0) {
	throw new IllegalArgumentException("len < 0");
	}

	List<byte[]> bufs = null;
	byte[] result = null;
	int total = 0;
	int remaining = len;
	int n;
	do {
	byte[] buf = new byte[Math.min(remaining, DEFAULT_BUFFER_SIZE)];
	int nread = 0;

	// read to EOF which may read more or less than buffer size
	while ((n = read(buf, nread,
	Math.min(buf.length - nread, remaining))) > 0) {
	nread += n;
	remaining -= n;
	}

	if (nread > 0) {
	if (MAX_BUFFER_SIZE - total < nread) {
	throw new OutOfMemoryError("Required array size too large");
	}
	if (nread < buf.length) {
	buf = Arrays.copyOfRange(buf, 0, nread);
	}
	total += nread;
	if (result == null) {
	result = buf;
	} else {
	if (bufs == null) {
	bufs = new ArrayList<>();
	bufs.add(result);
	}
	bufs.add(buf);
	}
	}
	// if the last call to read returned -1 or the number of bytes
	// requested have been read then break
	} while (n >= 0 && remaining > 0);

	if (bufs == null) {
	if (result == null) {
	return new byte[0];
	}
	return result.length == total ?
	result : Arrays.copyOf(result, total);
	}

	result = new byte[total];
	int offset = 0;
	remaining = total;
	for (byte[] b : bufs) {
	int count = Math.min(b.length, remaining);
	System.arraycopy(b, 0, result, offset, count);
	offset += count;
	remaining -= count;
	}

	return result;
	}

	/**
	* Reads the requested number of bytes from the input stream into the given
	* byte array. This method blocks until {@code len} bytes of input data have
	* been read, end of stream is detected, or an exception is thrown. The
	* number of bytes actually read, possibly zero, is returned. This method
	* does not close the input stream.
	*
	* <p> In the case where end of stream is reached before {@code len} bytes
	* have been read, then the actual number of bytes read will be returned.
	* When this stream reaches end of stream, further invocations of this
	* method will return zero.
	*
	* <p> If {@code len} is zero, then no bytes are read and {@code 0} is
	* returned; otherwise, there is an attempt to read up to {@code len} bytes.
	*
	* <p> The first byte read is stored into element {@code b[off]}, the next
	* one in to {@code b[off+1]}, and so on. The number of bytes read is, at
	* most, equal to {@code len}. Let <i>k</i> be the number of bytes actually
	* read; these bytes will be stored in elements {@code b[off]} through
	* {@code b[off+}<i>k</i>{@code -1]}, leaving elements {@code b[off+}<i>k</i>
	* {@code ]} through {@code b[off+len-1]} unaffected.
	*
	* <p> The behavior for the case where the input stream is <i>asynchronously
	* closed</i>, or the thread interrupted during the read, is highly input
	* stream specific, and therefore not specified.
	*
	* <p> If an I/O error occurs reading from the input stream, then it may do
	* so after some, but not all, bytes of {@code b} have been updated with
	* data from the input stream. Consequently the input stream and {@code b}
	* may be in an inconsistent state. It is strongly recommended that the
	* stream be promptly closed if an I/O error occurs.
	*
	* @param b the byte array into which the data is read
	* @param off the start offset in {@code b} at which the data is written
	* @param len the maximum number of bytes to read
	* @return the actual number of bytes read into the buffer
	* @throws IOException if an I/O error occurs
	* @throws NullPointerException if {@code b} is {@code null}
	* @throws IndexOutOfBoundsException If {@code off} is negative, {@code len}
	* is negative, or {@code len} is greater than {@code b.length - off}
	*
	* @since 9
	*/
	public int readNBytes(byte[] b, int off, int len) throws IOException {
	Objects.checkFromIndexSize(off, len, b.length);

	int n = 0;
	while (n < len) {
	int count = read(b, off + n, len - n);
	if (count < 0)
	break;
	n += count;
	}
	return n;
	}

	/**
	* Skips over and discards {@code n} bytes of data from this input
	* stream. The {@code skip} method may, for a variety of reasons, end
	* up skipping over some smaller number of bytes, possibly {@code 0}.
	* This may result from any of a number of conditions; reaching end of file
	* before {@code n} bytes have been skipped is only one possibility.
	* The actual number of bytes skipped is returned. If {@code n} is
	* negative, the {@code skip} method for class {@code InputStream} always
	* returns 0, and no bytes are skipped. Subclasses may handle the negative
	* value differently.
	*
	* <p> The {@code skip} method implementation of this class creates a
	* byte array and then repeatedly reads into it until {@code 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.
	*
	* @param n the number of bytes to be skipped.
	* @return the actual number of bytes skipped which might be zero.
	* @throws IOException if an I/O error occurs.
	* @see java.io.InputStream#skipNBytes(long)
	*/
	public long skip(long n) throws IOException {
	long remaining = n;
	int nr;

	if (n <= 0) {
	return 0;
	}

	int size = (int)Math.min(MAX_SKIP_BUFFER_SIZE, remaining);
	byte[] skipBuffer = new byte[size];
	while (remaining > 0) {
	nr = read(skipBuffer, 0, (int)Math.min(size, remaining));
	if (nr < 0) {
	break;
	}
	remaining -= nr;
	}

	return n - remaining;
	}

	/**
	* Skips over and discards exactly {@code n} bytes of data from this input
	* stream. If {@code n} is zero, then no bytes are skipped.
	* If {@code n} is negative, then no bytes are skipped.
	* Subclasses may handle the negative value differently.
	*
	* <p> This method blocks until the requested number of bytes has been
	* skipped, end of file is reached, or an exception is thrown.
	*
	* <p> If end of stream is reached before the stream is at the desired
	* position, then an {@code EOFException} is thrown.
	*
	* <p> If an I/O error occurs, then the input stream may be
	* in an inconsistent state. It is strongly recommended that the
	* stream be promptly closed if an I/O error occurs.
	*
	* @implNote
	* Subclasses are encouraged to provide a more efficient implementation
	* of this method.
	*
	* @implSpec
	* If {@code n} is zero or negative, then no bytes are skipped.
	* If {@code n} is positive, the default implementation of this method
	* invokes {@link #skip(long) skip()} repeatedly with its parameter equal
	* to the remaining number of bytes to skip until the requested number
	* of bytes has been skipped or an error condition occurs. If at any
	* point the return value of {@code skip()} is negative or greater than the
	* remaining number of bytes to be skipped, then an {@code IOException} is
	* thrown. If {@code skip()} ever returns zero, then {@link #read()} is
	* invoked to read a single byte, and if it returns {@code -1}, then an
	* {@code EOFException} is thrown. Any exception thrown by {@code skip()}
	* or {@code read()} will be propagated.
	*
	* @param n the number of bytes to be skipped.
	* @throws EOFException if end of stream is encountered before the
	* stream can be positioned {@code n} bytes beyond its position
	* when this method was invoked.
	* @throws IOException if the stream cannot be positioned properly or
	* if an I/O error occurs.
	* @see java.io.InputStream#skip(long)
	*
	* @since 12
	*/
	public void skipNBytes(long n) throws IOException {
	while (n > 0) {
	long ns = skip(n);
	if (ns > 0 && ns <= n) {
	// adjust number to skip
	n -= ns;
	} else if (ns == 0) { // no bytes skipped
	// read one byte to check for EOS
	if (read() == -1) {
	throw new EOFException();
	}
	// one byte read so decrement number to skip
	n--;
	} else { // skipped negative or too many bytes
	throw new IOException("Unable to skip exactly");
	}
	}
	}

	/**
	* Returns an estimate of the number of bytes that can be read (or skipped
	* over) from this input stream without blocking, which may be 0, or 0 when
	* end of stream is detected. The read might be on the same thread or
	* another thread. A single read or skip of this many bytes will not block,
	* but may read or skip fewer bytes.
	*
	* <p> Note that while some implementations of {@code InputStream} will
	* return the total number of bytes in the stream, many will not. It is
	* never correct to use the return value of this method to allocate
	* a buffer intended to hold all data in this stream.
	*
	* <p> A subclass's implementation of this method may choose to throw an
	* {@link IOException} if this input stream has been closed by invoking the
	* {@link #close()} method.
	*
	* <p> The {@code available} method of {@code InputStream} always returns
	* {@code 0}.
	*
	* <p> This method should be overridden by subclasses.
	*
	* @return an estimate of the number of bytes that can be read (or
	* skipped over) from this input stream without blocking or
	* {@code 0} when it reaches the end of the input stream.
	* @throws IOException if an I/O error occurs.
	*/
	public int available() throws IOException {
	return 0;
	}

	/**
	* Closes this input stream and releases any system resources associated
	* with the stream.
	*
	* <p> The {@code close} method of {@code InputStream} does
	* nothing.
	*
	* @throws IOException if an I/O error occurs.
	*/
	public void close() throws IOException {}

	/**
	* Marks the current position in this input stream. A subsequent call to
	* the {@code reset} method repositions this stream at the last marked
	* position so that subsequent reads re-read the same bytes.
	*
	* <p> The {@code readlimit} arguments tells this input stream to
	* allow that many bytes to be read before the mark position gets
	* invalidated.
	*
	* <p> The general contract of {@code mark} is that, if the method
	* {@code markSupported} returns {@code true}, the stream somehow
	* remembers all the bytes read after the call to {@code mark} and
	* stands ready to supply those same bytes again if and whenever the method
	* {@code reset} is called. However, the stream is not required to
	* remember any data at all if more than {@code readlimit} bytes are
	* read from the stream before {@code reset} is called.
	*
	* <p> Marking a closed stream should not have any effect on the stream.
	*
	* <p> The {@code mark} method of {@code InputStream} does
	* nothing.
	*
	* @param readlimit the maximum limit of bytes that can be read before
	* the mark position becomes invalid.
	* @see java.io.InputStream#reset()
	*/
	public synchronized void mark(int readlimit) {}

	/**
	* Repositions this stream to the position at the time the
	* {@code mark} method was last called on this input stream.
	*
	* <p> The general contract of {@code reset} is:
	*
	* <ul>
	* <li> If the method {@code markSupported} returns
	* {@code true}, then:
	*
	* <ul><li> If the method {@code mark} has not been called since
	* the stream was created, or the number of bytes read from the stream
	* since {@code mark} was last called is larger than the argument
	* to {@code mark} at that last call, then an
	* {@code IOException} might be thrown.
	*
	* <li> If such an {@code IOException} is not thrown, then the
	* stream is reset to a state such that all the bytes read since the
	* most recent call to {@code mark} (or since the start of the
	* file, if {@code mark} has not been called) will be resupplied
	* to subsequent callers of the {@code read} method, followed by
	* any bytes that otherwise would have been the next input data as of
	* the time of the call to {@code reset}. </ul>
	*
	* <li> If the method {@code markSupported} returns
	* {@code false}, then:
	*
	* <ul><li> The call to {@code reset} may throw an
	* {@code IOException}.
	*
	* <li> If an {@code 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 {@code read} method depend on the
	* particular type of the input stream. </ul></ul>
	*
	* <p>The method {@code reset} for class {@code InputStream}
	* does nothing except throw an {@code IOException}.
	*
	* @throws IOException if this stream has not been marked or if the
	* mark has been invalidated.
	* @see java.io.InputStream#mark(int)
	* @see java.io.IOException
	*/
	public synchronized void reset() throws IOException {
	throw new IOException("mark/reset not supported");
	}

	/**
	* Tests if this input stream supports the {@code mark} and
	* {@code reset} methods. Whether or not {@code mark} and
	* {@code reset} are supported is an invariant property of a
	* particular input stream instance. The {@code markSupported} method
	* of {@code InputStream} returns {@code false}.
	*
	* @return {@code true} if this stream instance supports the mark
	* and reset methods; {@code false} otherwise.
	* @see java.io.InputStream#mark(int)
	* @see java.io.InputStream#reset()
	*/
	public boolean markSupported() {
	return false;
	}

	/**
	* Reads all bytes from this input stream and writes the bytes to the
	* given output stream in the order that they are read. On return, this
	* input stream will be at end of stream. This method does not close either
	* stream.
	* <p>
	* This method may block indefinitely reading from the input stream, or
	* writing to the output stream. The behavior for the case where the input
	* and/or output stream is <i>asynchronously closed</i>, or the thread
	* interrupted during the transfer, is highly input and output stream
	* specific, and therefore not specified.
	* <p>
	* If an I/O error occurs reading from the input stream or writing to the
	* output stream, then it may do so after some bytes have been read or
	* written. Consequently the input stream may not be at end of stream and
	* one, or both, streams may be in an inconsistent state. It is strongly
	* recommended that both streams be promptly closed if an I/O error occurs.
	*
	* @param out the output stream, non-null
	* @return the number of bytes transferred
	* @throws IOException if an I/O error occurs when reading or writing
	* @throws NullPointerException if {@code out} is {@code null}
	*
	* @since 9
	*/
	public long transferTo(OutputStream out) throws IOException {
	Objects.requireNonNull(out, "out");
	long transferred = 0;
	byte[] buffer = new byte[DEFAULT_BUFFER_SIZE];
	int read;
	while ((read = this.read(buffer, 0, DEFAULT_BUFFER_SIZE)) >= 0) {
	out.write(buffer, 0, read);
	transferred += read;
	}
	return transferred;
	}
	}

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