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	/*
	* Copyright (c) 1996, 2013, 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;


	/**
	* Writes text to a character-output stream, buffering characters so as to
	* provide for the efficient writing of single characters, arrays, and strings.
	*
	* <p> The buffer size may be specified, or the default size may be accepted.
	* The default is large enough for most purposes.
	*
	* <p> A newLine() method is provided, which uses the platform's own notion of
	* line separator as defined by the system property <tt>line.separator</tt>.
	* Not all platforms use the newline character ('\n') to terminate lines.
	* Calling this method to terminate each output line is therefore preferred to
	* writing a newline character directly.
	*
	* <p> In general, a Writer sends its output immediately to the underlying
	* character or byte stream. Unless prompt output is required, it is advisable
	* to wrap a BufferedWriter around any Writer whose write() operations may be
	* costly, such as FileWriters and OutputStreamWriters. For example,
	*
	* <pre>
	* PrintWriter out
	* = new PrintWriter(new BufferedWriter(new FileWriter("foo.out")));
	* </pre>
	*
	* will buffer the PrintWriter's output to the file. Without buffering, each
	* invocation of a print() method would cause characters to be converted into
	* bytes that would then be written immediately to the file, which can be very
	* inefficient.
	*
	* @see PrintWriter
	* @see FileWriter
	* @see OutputStreamWriter
	* @see java.nio.file.Files#newBufferedWriter
	*
	* @author Mark Reinhold
	* @since JDK1.1
	*/

	public class BufferedWriter extends Writer {

	private Writer out;

	private char cb[];
	private int nChars, nextChar;

	private static int defaultCharBufferSize = 8192;

	/**
	* Line separator string. This is the value of the line.separator
	* property at the moment that the stream was created.
	*/
	private String lineSeparator;

	/**
	* Creates a buffered character-output stream that uses a default-sized
	* output buffer.
	*
	* @param out A Writer
	*/
	public BufferedWriter(Writer out) {
	this(out, defaultCharBufferSize);
	}

	/**
	* Creates a new buffered character-output stream that uses an output
	* buffer of the given size.
	*
	* @param out A Writer
	* @param sz Output-buffer size, a positive integer
	*
	* @exception IllegalArgumentException If {@code sz <= 0}
	*/
	public BufferedWriter(Writer out, int sz) {
	super(out);
	if (sz <= 0)
	throw new IllegalArgumentException("Buffer size <= 0");
	this.out = out;
	cb = new char[sz];
	nChars = sz;
	nextChar = 0;

	lineSeparator = java.security.AccessController.doPrivileged(
	new sun.security.action.GetPropertyAction("line.separator"));
	}

	/** Checks to make sure that the stream has not been closed */
	private void ensureOpen() throws IOException {
	if (out == null)
	throw new IOException("Stream closed");
	}

	/**
	* Flushes the output buffer to the underlying character stream, without
	* flushing the stream itself. This method is non-private only so that it
	* may be invoked by PrintStream.
	*/
	void flushBuffer() throws IOException {
	synchronized (lock) {
	ensureOpen();
	if (nextChar == 0)
	return;
	out.write(cb, 0, nextChar);
	nextChar = 0;
	}
	}

	/**
	* Writes a single character.
	*
	* @exception IOException If an I/O error occurs
	*/
	public void write(int c) throws IOException {
	synchronized (lock) {
	ensureOpen();
	if (nextChar >= nChars)
	flushBuffer();
	cb[nextChar++] = (char) c;
	}
	}

	/**
	* Our own little min method, to avoid loading java.lang.Math if we've run
	* out of file descriptors and we're trying to print a stack trace.
	*/
	private int min(int a, int b) {
	if (a < b) return a;
	return b;
	}

	/**
	* Writes a portion of an array of characters.
	*
	* <p> Ordinarily this method stores characters from the given array into
	* this stream's buffer, flushing the buffer to the underlying stream as
	* needed. If the requested length is at least as large as the buffer,
	* however, then this method will flush the buffer and write the characters
	* directly to the underlying stream. Thus redundant
	* <code>BufferedWriter</code>s will not copy data unnecessarily.
	*
	* @param cbuf A character array
	* @param off Offset from which to start reading characters
	* @param len Number of characters to write
	*
	* @exception IOException If an I/O error occurs
	*/
	public void write(char cbuf[], int off, int len) throws IOException {
	synchronized (lock) {
	ensureOpen();
	if ((off < 0) \|\| (off > cbuf.length) \|\| (len < 0) \|\|
	((off + len) > cbuf.length) \|\| ((off + len) < 0)) {
	throw new IndexOutOfBoundsException();
	} else if (len == 0) {
	return;
	}

	if (len >= nChars) {
	/* If the request length exceeds the size of the output buffer,
	flush the buffer and then write the data directly. In this
	way buffered streams will cascade harmlessly. */
	flushBuffer();
	out.write(cbuf, off, len);
	return;
	}

	int b = off, t = off + len;
	while (b < t) {
	int d = min(nChars - nextChar, t - b);
	System.arraycopy(cbuf, b, cb, nextChar, d);
	b += d;
	nextChar += d;
	if (nextChar >= nChars)
	flushBuffer();
	}
	}
	}

	/**
	* Writes a portion of a String.
	*
	* <p> If the value of the <tt>len</tt> parameter is negative then no
	* characters are written. This is contrary to the specification of this
	* method in the {@linkplain java.io.Writer#write(java.lang.String,int,int)
	* superclass}, which requires that an {@link IndexOutOfBoundsException} be
	* thrown.
	*
	* @param s String to be written
	* @param off Offset from which to start reading characters
	* @param len Number of characters to be written
	*
	* @exception IOException If an I/O error occurs
	*/
	public void write(String s, int off, int len) throws IOException {
	synchronized (lock) {
	ensureOpen();

	int b = off, t = off + len;
	while (b < t) {
	int d = min(nChars - nextChar, t - b);
	s.getChars(b, b + d, cb, nextChar);
	b += d;
	nextChar += d;
	if (nextChar >= nChars)
	flushBuffer();
	}
	}
	}

	/**
	* Writes a line separator. The line separator string is defined by the
	* system property <tt>line.separator</tt>, and is not necessarily a single
	* newline ('\n') character.
	*
	* @exception IOException If an I/O error occurs
	*/
	public void newLine() throws IOException {
	write(lineSeparator);
	}

	/**
	* Flushes the stream.
	*
	* @exception IOException If an I/O error occurs
	*/
	public void flush() throws IOException {
	synchronized (lock) {
	flushBuffer();
	out.flush();
	}
	}

	@SuppressWarnings("try")
	public void close() throws IOException {
	synchronized (lock) {
	if (out == null) {
	return;
	}
	try (Writer w = out) {
	flushBuffer();
	} finally {
	out = null;
	cb = null;
	}
	}
	}
	}

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