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	/*
	* Copyright (c) 1995, 2019, 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;

	/**
	* This class is an input stream filter that provides the added
	* functionality of keeping track of the current line number.
	* <p>
	* A line is a sequence of bytes ending with a carriage return
	* character ({@code '\u005Cr'}), a newline character
	* ({@code '\u005Cn'}), or a carriage return character followed
	* immediately by a linefeed character. In all three cases, the line
	* terminating character(s) are returned as a single newline character.
	* <p>
	* The line number begins at {@code 0}, and is incremented by
	* {@code 1} when a {@code read} returns a newline character.
	*
	* @author Arthur van Hoff
	* @see java.io.LineNumberReader
	* @since 1.0
	* @deprecated This class incorrectly assumes that bytes adequately represent
	* characters. As of JDK 1.1, the preferred way to operate on
	* character streams is via the new character-stream classes, which
	* include a class for counting line numbers.
	*/
	@Deprecated
	public class LineNumberInputStream extends FilterInputStream {
	int pushBack = -1;
	int lineNumber;
	int markLineNumber;
	int markPushBack = -1;

	/**
	* Constructs a newline number input stream that reads its input
	* from the specified input stream.
	*
	* @param in the underlying input stream.
	*/
	public LineNumberInputStream(InputStream in) {
	super(in);
	}

	/**
	* Reads the next byte of data from this 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>
	* The {@code read} method of
	* {@code LineNumberInputStream} calls the {@code read}
	* method of the underlying input stream. It checks for carriage
	* returns and newline characters in the input, and modifies the
	* current line number as appropriate. A carriage-return character or
	* a carriage return followed by a newline character are both
	* converted into a single newline character.
	*
	* @return the next byte of data, or {@code -1} if the end of this
	* stream is reached.
	* @throws IOException if an I/O error occurs.
	* @see java.io.FilterInputStream#in
	* @see java.io.LineNumberInputStream#getLineNumber()
	*/
	@SuppressWarnings("fallthrough")
	public int read() throws IOException {
	int c = pushBack;

	if (c != -1) {
	pushBack = -1;
	} else {
	c = in.read();
	}

	switch (c) {
	case '\r':
	pushBack = in.read();
	if (pushBack == '\n') {
	pushBack = -1;
	}
	case '\n':
	lineNumber++;
	return '\n';
	}
	return c;
	}

	/**
	* Reads up to {@code len} bytes of data from this input stream
	* into an array of bytes. This method blocks until some input is available.
	* <p>
	* The {@code read} method of
	* {@code LineNumberInputStream} repeatedly calls the
	* {@code read} method of zero arguments to fill in the byte array.
	*
	* @param b the buffer into which the data is read.
	* @param off the start offset of the data.
	* @param len the maximum number of bytes read.
	* @return the total number of bytes read into the buffer, or
	* {@code -1} if there is no more data because the end of
	* this stream has been reached.
	* @throws IOException if an I/O error occurs.
	* @see java.io.LineNumberInputStream#read()
	*/
	public int read(byte b[], int off, int len) throws IOException {
	if (b == null) {
	throw new NullPointerException();
	} else if ((off < 0) \|\| (off > b.length) \|\| (len < 0) \|\|
	((off + len) > b.length) \|\| ((off + len) < 0)) {
	throw new IndexOutOfBoundsException();
	} else 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;
	}
	if (b != null) {
	b[off + i] = (byte)c;
	}
	}
	} catch (IOException ee) {
	}
	return i;
	}

	/**
	* 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}. The actual number of bytes skipped is
	* returned. If {@code n} is negative, no bytes are skipped.
	* <p>
	* The {@code skip} method of {@code LineNumberInputStream} 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.
	*
	* @param n the number of bytes to be skipped.
	* @return the actual number of bytes skipped.
	* @throws IOException if an I/O error occurs.
	* @see java.io.FilterInputStream#in
	*/
	public long skip(long n) throws IOException {
	int chunk = 2048;
	long remaining = n;
	byte data[];
	int nr;

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

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

	return n - remaining;
	}

	/**
	* Sets the line number to the specified argument.
	*
	* @param lineNumber the new line number.
	* @see #getLineNumber
	*/
	public void setLineNumber(int lineNumber) {
	this.lineNumber = lineNumber;
	}

	/**
	* Returns the current line number.
	*
	* @return the current line number.
	* @see #setLineNumber
	*/
	public int getLineNumber() {
	return lineNumber;
	}


	/**
	* Returns the number of bytes that can be read from this input
	* stream without blocking.
	* <p>
	* Note that if the underlying input stream is able to supply
	* <i>k</i> input characters without blocking, the
	* {@code LineNumberInputStream} can guarantee only to provide
	* <i>k</i>/2 characters without blocking, because the
	* <i>k</i> characters from the underlying input stream might
	* consist of <i>k</i>/2 pairs of {@code '\u005Cr'} and
	* {@code '\u005Cn'}, which are converted to just
	* <i>k</i>/2 {@code '\u005Cn'} characters.
	*
	* @return the number of bytes that can be read from this input stream
	* without blocking.
	* @throws IOException if an I/O error occurs.
	* @see java.io.FilterInputStream#in
	*/
	public int available() throws IOException {
	return (pushBack == -1) ? super.available()/2 : super.available()/2 + 1;
	}

	/**
	* 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 mark} method of
	* {@code LineNumberInputStream} remembers the current line
	* number in a private variable, and then calls the {@code mark}
	* method of the underlying input stream.
	*
	* @param readlimit the maximum limit of bytes that can be read before
	* the mark position becomes invalid.
	* @see java.io.FilterInputStream#in
	* @see java.io.LineNumberInputStream#reset()
	*/
	public void mark(int readlimit) {
	markLineNumber = lineNumber;
	markPushBack = pushBack;
	in.mark(readlimit);
	}

	/**
	* Repositions this stream to the position at the time the
	* {@code mark} method was last called on this input stream.
	* <p>
	* The {@code reset} method of
	* {@code LineNumberInputStream} resets the line number to be
	* the line number at the time the {@code mark} method was
	* called, and then calls the {@code reset} method of the
	* underlying input stream.
	* <p>
	* Stream marks are intended to be used in
	* situations where you need to read ahead a little to see what's in
	* the stream. Often this is most easily done by invoking some
	* general parser. If the stream is of the type handled by the
	* parser, it just chugs along happily. If the stream is not of
	* that type, the parser should toss an exception when it fails,
	* which, if it happens within readlimit bytes, allows the outer
	* code to reset the stream and try another parser.
	*
	* @throws IOException if an I/O error occurs.
	* @see java.io.FilterInputStream#in
	* @see java.io.LineNumberInputStream#mark(int)
	*/
	public void reset() throws IOException {
	lineNumber = markLineNumber;
	pushBack = markPushBack;
	in.reset();
	}
	}

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