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	/*
	* Copyright (c) 1996, 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.Formatter;
	import java.util.Locale;
	import java.nio.charset.Charset;
	import java.nio.charset.IllegalCharsetNameException;
	import java.nio.charset.UnsupportedCharsetException;

	/**
	* A {@code PrintStream} adds functionality to another output stream,
	* namely the ability to print representations of various data values
	* conveniently. Two other features are provided as well. Unlike other output
	* streams, a {@code PrintStream} never throws an
	* {@code IOException}; instead, exceptional situations merely set an
	* internal flag that can be tested via the {@code checkError} method.
	* Optionally, a {@code PrintStream} can be created so as to flush
	* automatically; this means that the {@code flush} method of the underlying
	* output stream is automatically invoked after a byte array is written, one
	* of the {@code println} methods is invoked, or a newline character or byte
	* ({@code '\n'}) is written.
	*
	* <p> All characters printed by a {@code PrintStream} are converted into
	* bytes using the given encoding or charset, or the platform's default
	* character encoding if not specified.
	* The {@link PrintWriter} class should be used in situations that require
	* writing characters rather than bytes.
	*
	* <p> This class always replaces malformed and unmappable character sequences
	* with the charset's default replacement string.
	* The {@linkplain java.nio.charset.CharsetEncoder} class should be used when more
	* control over the encoding process is required.
	*
	* @author Frank Yellin
	* @author Mark Reinhold
	* @since 1.0
	*/

	public class PrintStream extends FilterOutputStream
	implements Appendable, Closeable
	{

	private final boolean autoFlush;
	private boolean trouble = false;
	private Formatter formatter;

	/**
	* Track both the text- and character-output streams, so that their buffers
	* can be flushed without flushing the entire stream.
	*/
	private BufferedWriter textOut;
	private OutputStreamWriter charOut;

	/**
	* requireNonNull is explicitly declared here so as not to create an extra
	* dependency on java.util.Objects.requireNonNull. PrintStream is loaded
	* early during system initialization.
	*/
	private static <T> T requireNonNull(T obj, String message) {
	if (obj == null)
	throw new NullPointerException(message);
	return obj;
	}

	/**
	* Returns a charset object for the given charset name.
	* @throws NullPointerException is csn is null
	* @throws UnsupportedEncodingException if the charset is not supported
	*/
	private static Charset toCharset(String csn)
	throws UnsupportedEncodingException
	{
	requireNonNull(csn, "charsetName");
	try {
	return Charset.forName(csn);
	} catch (IllegalCharsetNameException\|UnsupportedCharsetException unused) {
	// UnsupportedEncodingException should be thrown
	throw new UnsupportedEncodingException(csn);
	}
	}

	/* Private constructors */
	private PrintStream(boolean autoFlush, OutputStream out) {
	super(out);
	this.autoFlush = autoFlush;
	this.charOut = new OutputStreamWriter(this);
	this.textOut = new BufferedWriter(charOut);
	}

	/* Variant of the private constructor so that the given charset name
	* can be verified before evaluating the OutputStream argument. Used
	* by constructors creating a FileOutputStream that also take a
	* charset name.
	*/
	private PrintStream(boolean autoFlush, Charset charset, OutputStream out) {
	this(out, autoFlush, charset);
	}

	/**
	* Creates a new print stream, without automatic line flushing, with the
	* specified OutputStream. Characters written to the stream are converted
	* to bytes using the platform's default character encoding.
	*
	* @param out The output stream to which values and objects will be
	* printed
	*
	* @see java.io.PrintWriter#PrintWriter(java.io.OutputStream)
	*/
	public PrintStream(OutputStream out) {
	this(out, false);
	}

	/**
	* Creates a new print stream, with the specified OutputStream and line
	* flushing. Characters written to the stream are converted to bytes using
	* the platform's default character encoding.
	*
	* @param out The output stream to which values and objects will be
	* printed
	* @param autoFlush Whether the output buffer will be flushed
	* whenever a byte array is written, one of the
	* {@code println} methods is invoked, or a newline
	* character or byte ({@code '\n'}) is written
	*
	* @see java.io.PrintWriter#PrintWriter(java.io.OutputStream, boolean)
	*/
	public PrintStream(OutputStream out, boolean autoFlush) {
	this(autoFlush, requireNonNull(out, "Null output stream"));
	}

	/**
	* Creates a new print stream, with the specified OutputStream, line
	* flushing, and character encoding.
	*
	* @param out The output stream to which values and objects will be
	* printed
	* @param autoFlush Whether the output buffer will be flushed
	* whenever a byte array is written, one of the
	* {@code println} methods is invoked, or a newline
	* character or byte ({@code '\n'}) is written
	* @param encoding The name of a supported
	* <a href="../lang/package-summary.html#charenc">
	* character encoding</a>
	*
	* @throws UnsupportedEncodingException
	* If the named encoding is not supported
	*
	* @since 1.4
	*/
	public PrintStream(OutputStream out, boolean autoFlush, String encoding)
	throws UnsupportedEncodingException
	{
	this(requireNonNull(out, "Null output stream"), autoFlush, toCharset(encoding));
	}

	/**
	* Creates a new print stream, with the specified OutputStream, line
	* flushing and charset. This convenience constructor creates the necessary
	* intermediate {@link java.io.OutputStreamWriter OutputStreamWriter},
	* which will encode characters using the provided charset.
	*
	* @param out The output stream to which values and objects will be
	* printed
	* @param autoFlush Whether the output buffer will be flushed
	* whenever a byte array is written, one of the
	* {@code println} methods is invoked, or a newline
	* character or byte ({@code '\n'}) is written
	* @param charset A {@linkplain java.nio.charset.Charset charset}
	*
	* @since 10
	*/
	public PrintStream(OutputStream out, boolean autoFlush, Charset charset) {
	super(out);
	this.autoFlush = autoFlush;
	this.charOut = new OutputStreamWriter(this, charset);
	this.textOut = new BufferedWriter(charOut);
	}

	/**
	* Creates a new print stream, without automatic line flushing, with the
	* specified file name. This convenience constructor creates
	* the necessary intermediate {@link java.io.OutputStreamWriter
	* OutputStreamWriter}, which will encode characters using the
	* {@linkplain java.nio.charset.Charset#defaultCharset() default charset}
	* for this instance of the Java virtual machine.
	*
	* @param fileName
	* The name of the file to use as the destination of this print
	* stream. If the file exists, then it will be truncated to
	* zero size; otherwise, a new file will be created. The output
	* will be written to the file and is buffered.
	*
	* @throws FileNotFoundException
	* If the given file object does not denote an existing, writable
	* regular file and a new regular file of that name cannot be
	* created, or if some other error occurs while opening or
	* creating the file
	*
	* @throws SecurityException
	* If a security manager is present and {@link
	* SecurityManager#checkWrite checkWrite(fileName)} denies write
	* access to the file
	*
	* @since 1.5
	*/
	public PrintStream(String fileName) throws FileNotFoundException {
	this(false, new FileOutputStream(fileName));
	}

	/**
	* Creates a new print stream, without automatic line flushing, with the
	* specified file name and charset. This convenience constructor creates
	* the necessary intermediate {@link java.io.OutputStreamWriter
	* OutputStreamWriter}, which will encode characters using the provided
	* charset.
	*
	* @param fileName
	* The name of the file to use as the destination of this print
	* stream. If the file exists, then it will be truncated to
	* zero size; otherwise, a new file will be created. The output
	* will be written to the file and is buffered.
	*
	* @param csn
	* The name of a supported {@linkplain java.nio.charset.Charset
	* charset}
	*
	* @throws FileNotFoundException
	* If the given file object does not denote an existing, writable
	* regular file and a new regular file of that name cannot be
	* created, or if some other error occurs while opening or
	* creating the file
	*
	* @throws SecurityException
	* If a security manager is present and {@link
	* SecurityManager#checkWrite checkWrite(fileName)} denies write
	* access to the file
	*
	* @throws UnsupportedEncodingException
	* If the named charset is not supported
	*
	* @since 1.5
	*/
	public PrintStream(String fileName, String csn)
	throws FileNotFoundException, UnsupportedEncodingException
	{
	// ensure charset is checked before the file is opened
	this(false, toCharset(csn), new FileOutputStream(fileName));
	}

	/**
	* Creates a new print stream, without automatic line flushing, with the
	* specified file name and charset. This convenience constructor creates
	* the necessary intermediate {@link java.io.OutputStreamWriter
	* OutputStreamWriter}, which will encode characters using the provided
	* charset.
	*
	* @param fileName
	* The name of the file to use as the destination of this print
	* stream. If the file exists, then it will be truncated to
	* zero size; otherwise, a new file will be created. The output
	* will be written to the file and is buffered.
	*
	* @param charset
	* A {@linkplain java.nio.charset.Charset charset}
	*
	* @throws IOException
	* if an I/O error occurs while opening or creating the file
	*
	* @throws SecurityException
	* If a security manager is present and {@link
	* SecurityManager#checkWrite checkWrite(fileName)} denies write
	* access to the file
	*
	* @since 10
	*/
	public PrintStream(String fileName, Charset charset) throws IOException {
	this(false, requireNonNull(charset, "charset"), new FileOutputStream(fileName));
	}

	/**
	* Creates a new print stream, without automatic line flushing, with the
	* specified file. This convenience constructor creates the necessary
	* intermediate {@link java.io.OutputStreamWriter OutputStreamWriter},
	* which will encode characters using the {@linkplain
	* java.nio.charset.Charset#defaultCharset() default charset} for this
	* instance of the Java virtual machine.
	*
	* @param file
	* The file to use as the destination of this print stream. If the
	* file exists, then it will be truncated to zero size; otherwise,
	* a new file will be created. The output will be written to the
	* file and is buffered.
	*
	* @throws FileNotFoundException
	* If the given file object does not denote an existing, writable
	* regular file and a new regular file of that name cannot be
	* created, or if some other error occurs while opening or
	* creating the file
	*
	* @throws SecurityException
	* If a security manager is present and {@link
	* SecurityManager#checkWrite checkWrite(file.getPath())}
	* denies write access to the file
	*
	* @since 1.5
	*/
	public PrintStream(File file) throws FileNotFoundException {
	this(false, new FileOutputStream(file));
	}

	/**
	* Creates a new print stream, without automatic line flushing, with the
	* specified file and charset. This convenience constructor creates
	* the necessary intermediate {@link java.io.OutputStreamWriter
	* OutputStreamWriter}, which will encode characters using the provided
	* charset.
	*
	* @param file
	* The file to use as the destination of this print stream. If the
	* file exists, then it will be truncated to zero size; otherwise,
	* a new file will be created. The output will be written to the
	* file and is buffered.
	*
	* @param csn
	* The name of a supported {@linkplain java.nio.charset.Charset
	* charset}
	*
	* @throws FileNotFoundException
	* If the given file object does not denote an existing, writable
	* regular file and a new regular file of that name cannot be
	* created, or if some other error occurs while opening or
	* creating the file
	*
	* @throws SecurityException
	* If a security manager is present and {@link
	* SecurityManager#checkWrite checkWrite(file.getPath())}
	* denies write access to the file
	*
	* @throws UnsupportedEncodingException
	* If the named charset is not supported
	*
	* @since 1.5
	*/
	public PrintStream(File file, String csn)
	throws FileNotFoundException, UnsupportedEncodingException
	{
	// ensure charset is checked before the file is opened
	this(false, toCharset(csn), new FileOutputStream(file));
	}


	/**
	* Creates a new print stream, without automatic line flushing, with the
	* specified file and charset. This convenience constructor creates
	* the necessary intermediate {@link java.io.OutputStreamWriter
	* OutputStreamWriter}, which will encode characters using the provided
	* charset.
	*
	* @param file
	* The file to use as the destination of this print stream. If the
	* file exists, then it will be truncated to zero size; otherwise,
	* a new file will be created. The output will be written to the
	* file and is buffered.
	*
	* @param charset
	* A {@linkplain java.nio.charset.Charset charset}
	*
	* @throws IOException
	* if an I/O error occurs while opening or creating the file
	*
	* @throws SecurityException
	* If a security manager is present and {@link
	* SecurityManager#checkWrite checkWrite(file.getPath())}
	* denies write access to the file
	*
	* @since 10
	*/
	public PrintStream(File file, Charset charset) throws IOException {
	this(false, requireNonNull(charset, "charset"), new FileOutputStream(file));
	}

	/** Check 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 stream. This is done by writing any buffered output bytes to
	* the underlying output stream and then flushing that stream.
	*
	* @see java.io.OutputStream#flush()
	*/
	@Override
	public void flush() {
	synchronized (this) {
	try {
	ensureOpen();
	out.flush();
	}
	catch (IOException x) {
	trouble = true;
	}
	}
	}

	private boolean closing = false; /* To avoid recursive closing */

	/**
	* Closes the stream. This is done by flushing the stream and then closing
	* the underlying output stream.
	*
	* @see java.io.OutputStream#close()
	*/
	@Override
	public void close() {
	synchronized (this) {
	if (! closing) {
	closing = true;
	try {
	textOut.close();
	out.close();
	}
	catch (IOException x) {
	trouble = true;
	}
	textOut = null;
	charOut = null;
	out = null;
	}
	}
	}

	/**
	* Flushes the stream and checks its error state. The internal error state
	* is set to {@code true} when the underlying output stream throws an
	* {@code IOException} other than {@code InterruptedIOException},
	* and when the {@code setError} method is invoked. If an operation
	* on the underlying output stream throws an
	* {@code InterruptedIOException}, then the {@code PrintStream}
	* converts the exception back into an interrupt by doing:
	* <pre>{@code
	* Thread.currentThread().interrupt();
	* }</pre>
	* or the equivalent.
	*
	* @return {@code true} if and only if this stream has encountered an
	* {@code IOException} other than
	* {@code InterruptedIOException}, or the
	* {@code setError} method has been invoked
	*/
	public boolean checkError() {
	if (out != null)
	flush();
	if (out instanceof PrintStream ps) {
	return ps.checkError();
	}
	return trouble;
	}

	/**
	* Sets the error state of the stream to {@code true}.
	*
	* <p> This method will cause subsequent invocations of {@link
	* #checkError()} to return {@code true} until
	* {@link #clearError()} is invoked.
	*
	* @since 1.1
	*/
	protected void setError() {
	trouble = true;
	}

	/**
	* Clears the internal error state of this stream.
	*
	* <p> This method will cause subsequent invocations of {@link
	* #checkError()} to return {@code false} until another write
	* operation fails and invokes {@link #setError()}.
	*
	* @since 1.6
	*/
	protected void clearError() {
	trouble = false;
	}

	/*
	* Exception-catching, synchronized output operations,
	* which also implement the write() methods of OutputStream
	*/

	/**
	* Writes the specified byte to this stream. If the byte is a newline and
	* automatic flushing is enabled then the {@code flush} method will be
	* invoked on the underlying output stream.
	*
	* <p> Note that the byte is written as given; to write a character that
	* will be translated according to the platform's default character
	* encoding, use the {@code print(char)} or {@code println(char)}
	* methods.
	*
	* @param b The byte to be written
	* @see #print(char)
	* @see #println(char)
	*/
	@Override
	public void write(int b) {
	try {
	synchronized (this) {
	ensureOpen();
	out.write(b);
	if ((b == '\n') && autoFlush)
	out.flush();
	}
	}
	catch (InterruptedIOException x) {
	Thread.currentThread().interrupt();
	}
	catch (IOException x) {
	trouble = true;
	}
	}

	/**
	* Writes {@code len} bytes from the specified byte array starting at
	* offset {@code off} to this stream. If automatic flushing is
	* enabled then the {@code flush} method will be invoked on the underlying
	* output stream.
	*
	* <p> Note that the bytes will be written as given; to write characters
	* that will be translated according to the platform's default character
	* encoding, use the {@code print(char)} or {@code println(char)}
	* methods.
	*
	* @param buf A byte array
	* @param off Offset from which to start taking bytes
	* @param len Number of bytes to write
	*/
	@Override
	public void write(byte buf[], int off, int len) {
	try {
	synchronized (this) {
	ensureOpen();
	out.write(buf, off, len);
	if (autoFlush)
	out.flush();
	}
	}
	catch (InterruptedIOException x) {
	Thread.currentThread().interrupt();
	}
	catch (IOException x) {
	trouble = true;
	}
	}

	/**
	* Writes all bytes from the specified byte array to this stream. If
	* automatic flushing is enabled then the {@code flush} method will be
	* invoked on the underlying output stream.
	*
	* <p> Note that the bytes will be written as given; to write characters
	* that will be translated according to the platform's default character
	* encoding, use the {@code print(char[])} or {@code println(char[])}
	* methods.
	*
	* @apiNote
	* Although declared to throw {@code IOException}, this method never
	* actually does so. Instead, like other methods that this class
	* overrides, it sets an internal flag which may be tested via the
	* {@link #checkError()} method. To write an array of bytes without having
	* to write a {@code catch} block for the {@code IOException}, use either
	* {@link #writeBytes(byte[] buf) writeBytes(buf)} or
	* {@link #write(byte[], int, int) write(buf, 0, buf.length)}.
	*
	* @implSpec
	* This method is equivalent to
	* {@link java.io.PrintStream#write(byte[],int,int)
	* this.write(buf, 0, buf.length)}.
	*
	* @param buf A byte array
	*
	* @throws IOException If an I/O error occurs.
	*
	* @see #writeBytes(byte[])
	* @see #write(byte[],int,int)
	*
	* @since 14
	*/
	@Override
	public void write(byte buf[]) throws IOException {
	this.write(buf, 0, buf.length);
	}

	/**
	* Writes all bytes from the specified byte array to this stream.
	* If automatic flushing is enabled then the {@code flush} method
	* will be invoked.
	*
	* <p> Note that the bytes will be written as given; to write characters
	* that will be translated according to the platform's default character
	* encoding, use the {@code print(char[])} or {@code println(char[])}
	* methods.
	*
	* @implSpec
	* This method is equivalent to
	* {@link #write(byte[], int, int) this.write(buf, 0, buf.length)}.
	*
	* @param buf A byte array
	*
	* @since 14
	*/
	public void writeBytes(byte buf[]) {
	this.write(buf, 0, buf.length);
	}

	/*
	* The following private methods on the text- and character-output streams
	* always flush the stream buffers, so that writes to the underlying byte
	* stream occur as promptly as with the original PrintStream.
	*/

	private void write(char[] buf) {
	try {
	synchronized (this) {
	ensureOpen();
	textOut.write(buf);
	textOut.flushBuffer();
	charOut.flushBuffer();
	if (autoFlush) {
	for (int i = 0; i < buf.length; i++)
	if (buf[i] == '\n') {
	out.flush();
	break;
	}
	}
	}
	} catch (InterruptedIOException x) {
	Thread.currentThread().interrupt();
	} catch (IOException x) {
	trouble = true;
	}
	}

	// Used to optimize away back-to-back flushing and synchronization when
	// using println, but since subclasses could exist which depend on
	// observing a call to print followed by newLine() we only use this if
	// getClass() == PrintStream.class to avoid compatibility issues.
	private void writeln(char[] buf) {
	try {
	synchronized (this) {
	ensureOpen();
	textOut.write(buf);
	textOut.newLine();
	textOut.flushBuffer();
	charOut.flushBuffer();
	if (autoFlush)
	out.flush();
	}
	}
	catch (InterruptedIOException x) {
	Thread.currentThread().interrupt();
	}
	catch (IOException x) {
	trouble = true;
	}
	}

	private void write(String s) {
	try {
	synchronized (this) {
	ensureOpen();
	textOut.write(s);
	textOut.flushBuffer();
	charOut.flushBuffer();
	if (autoFlush && (s.indexOf('\n') >= 0))
	out.flush();
	}
	}
	catch (InterruptedIOException x) {
	Thread.currentThread().interrupt();
	}
	catch (IOException x) {
	trouble = true;
	}
	}

	// Used to optimize away back-to-back flushing and synchronization when
	// using println, but since subclasses could exist which depend on
	// observing a call to print followed by newLine we only use this if
	// getClass() == PrintStream.class to avoid compatibility issues.
	private void writeln(String s) {
	try {
	synchronized (this) {
	ensureOpen();
	textOut.write(s);
	textOut.newLine();
	textOut.flushBuffer();
	charOut.flushBuffer();
	if (autoFlush)
	out.flush();
	}
	}
	catch (InterruptedIOException x) {
	Thread.currentThread().interrupt();
	}
	catch (IOException x) {
	trouble = true;
	}
	}

	private void newLine() {
	try {
	synchronized (this) {
	ensureOpen();
	textOut.newLine();
	textOut.flushBuffer();
	charOut.flushBuffer();
	if (autoFlush)
	out.flush();
	}
	}
	catch (InterruptedIOException x) {
	Thread.currentThread().interrupt();
	}
	catch (IOException x) {
	trouble = true;
	}
	}

	/* Methods that do not terminate lines */

	/**
	* Prints a boolean value. The string produced by {@link
	* java.lang.String#valueOf(boolean)} is translated into bytes
	* according to the platform's default character encoding, and these bytes
	* are written in exactly the manner of the
	* {@link #write(int)} method.
	*
	* @param b The {@code boolean} to be printed
	*/
	public void print(boolean b) {
	write(String.valueOf(b));
	}

	/**
	* Prints a character. The character is translated into one or more bytes
	* according to the character encoding given to the constructor, or the
	* platform's default character encoding if none specified. These bytes
	* are written in exactly the manner of the {@link #write(int)} method.
	*
	* @param c The {@code char} to be printed
	*/
	public void print(char c) {
	write(String.valueOf(c));
	}

	/**
	* Prints an integer. The string produced by {@link
	* java.lang.String#valueOf(int)} is translated into bytes
	* according to the platform's default character encoding, and these bytes
	* are written in exactly the manner of the
	* {@link #write(int)} method.
	*
	* @param i The {@code int} to be printed
	* @see java.lang.Integer#toString(int)
	*/
	public void print(int i) {
	write(String.valueOf(i));
	}

	/**
	* Prints a long integer. The string produced by {@link
	* java.lang.String#valueOf(long)} is translated into bytes
	* according to the platform's default character encoding, and these bytes
	* are written in exactly the manner of the
	* {@link #write(int)} method.
	*
	* @param l The {@code long} to be printed
	* @see java.lang.Long#toString(long)
	*/
	public void print(long l) {
	write(String.valueOf(l));
	}

	/**
	* Prints a floating-point number. The string produced by {@link
	* java.lang.String#valueOf(float)} is translated into bytes
	* according to the platform's default character encoding, and these bytes
	* are written in exactly the manner of the
	* {@link #write(int)} method.
	*
	* @param f The {@code float} to be printed
	* @see java.lang.Float#toString(float)
	*/
	public void print(float f) {
	write(String.valueOf(f));
	}

	/**
	* Prints a double-precision floating-point number. The string produced by
	* {@link java.lang.String#valueOf(double)} is translated into
	* bytes according to the platform's default character encoding, and these
	* bytes are written in exactly the manner of the {@link
	* #write(int)} method.
	*
	* @param d The {@code double} to be printed
	* @see java.lang.Double#toString(double)
	*/
	public void print(double d) {
	write(String.valueOf(d));
	}

	/**
	* Prints an array of characters. The characters are converted into bytes
	* according to the character encoding given to the constructor, or the
	* platform's default character encoding if none specified. These bytes
	* are written in exactly the manner of the {@link #write(int)} method.
	*
	* @param s The array of chars to be printed
	*
	* @throws NullPointerException If {@code s} is {@code null}
	*/
	public void print(char s[]) {
	write(s);
	}

	/**
	* Prints a string. If the argument is {@code null} then the string
	* {@code "null"} is printed. Otherwise, the string's characters are
	* converted into bytes according to the character encoding given to the
	* constructor, or the platform's default character encoding if none
	* specified. These bytes are written in exactly the manner of the
	* {@link #write(int)} method.
	*
	* @param s The {@code String} to be printed
	*/
	public void print(String s) {
	write(String.valueOf(s));
	}

	/**
	* Prints an object. The string produced by the {@link
	* java.lang.String#valueOf(Object)} method is translated into bytes
	* according to the platform's default character encoding, and these bytes
	* are written in exactly the manner of the
	* {@link #write(int)} method.
	*
	* @param obj The {@code Object} to be printed
	* @see java.lang.Object#toString()
	*/
	public void print(Object obj) {
	write(String.valueOf(obj));
	}


	/* Methods that do terminate lines */

	/**
	* Terminates the current line by writing the line separator string. The
	* line separator string is defined by the system property
	* {@code line.separator}, and is not necessarily a single newline
	* character ({@code '\n'}).
	*/
	public void println() {
	newLine();
	}

	/**
	* Prints a boolean and then terminate the line. This method behaves as
	* though it invokes {@link #print(boolean)} and then
	* {@link #println()}.
	*
	* @param x The {@code boolean} to be printed
	*/
	public void println(boolean x) {
	if (getClass() == PrintStream.class) {
	writeln(String.valueOf(x));
	} else {
	synchronized (this) {
	print(x);
	newLine();
	}
	}
	}

	/**
	* Prints a character and then terminate the line. This method behaves as
	* though it invokes {@link #print(char)} and then
	* {@link #println()}.
	*
	* @param x The {@code char} to be printed.
	*/
	public void println(char x) {
	if (getClass() == PrintStream.class) {
	writeln(String.valueOf(x));
	} else {
	synchronized (this) {
	print(x);
	newLine();
	}
	}
	}

	/**
	* Prints an integer and then terminate the line. This method behaves as
	* though it invokes {@link #print(int)} and then
	* {@link #println()}.
	*
	* @param x The {@code int} to be printed.
	*/
	public void println(int x) {
	if (getClass() == PrintStream.class) {
	writeln(String.valueOf(x));
	} else {
	synchronized (this) {
	print(x);
	newLine();
	}
	}
	}

	/**
	* Prints a long and then terminate the line. This method behaves as
	* though it invokes {@link #print(long)} and then
	* {@link #println()}.
	*
	* @param x a The {@code long} to be printed.
	*/
	public void println(long x) {
	if (getClass() == PrintStream.class) {
	writeln(String.valueOf(x));
	} else {
	synchronized (this) {
	print(x);
	newLine();
	}
	}
	}

	/**
	* Prints a float and then terminate the line. This method behaves as
	* though it invokes {@link #print(float)} and then
	* {@link #println()}.
	*
	* @param x The {@code float} to be printed.
	*/
	public void println(float x) {
	if (getClass() == PrintStream.class) {
	writeln(String.valueOf(x));
	} else {
	synchronized (this) {
	print(x);
	newLine();
	}
	}
	}

	/**
	* Prints a double and then terminate the line. This method behaves as
	* though it invokes {@link #print(double)} and then
	* {@link #println()}.
	*
	* @param x The {@code double} to be printed.
	*/
	public void println(double x) {
	if (getClass() == PrintStream.class) {
	writeln(String.valueOf(x));
	} else {
	synchronized (this) {
	print(x);
	newLine();
	}
	}
	}

	/**
	* Prints an array of characters and then terminate the line. This method
	* behaves as though it invokes {@link #print(char[])} and
	* then {@link #println()}.
	*
	* @param x an array of chars to print.
	*/
	public void println(char[] x) {
	if (getClass() == PrintStream.class) {
	writeln(x);
	} else {
	synchronized (this) {
	print(x);
	newLine();
	}
	}
	}

	/**
	* Prints a String and then terminate the line. This method behaves as
	* though it invokes {@link #print(String)} and then
	* {@link #println()}.
	*
	* @param x The {@code String} to be printed.
	*/
	public void println(String x) {
	if (getClass() == PrintStream.class) {
	writeln(String.valueOf(x));
	} else {
	synchronized (this) {
	print(x);
	newLine();
	}
	}
	}

	/**
	* Prints an Object and then terminate the line. This method calls
	* at first String.valueOf(x) to get the printed object's string value,
	* then behaves as
	* though it invokes {@link #print(String)} and then
	* {@link #println()}.
	*
	* @param x The {@code Object} to be printed.
	*/
	public void println(Object x) {
	String s = String.valueOf(x);
	if (getClass() == PrintStream.class) {
	// need to apply String.valueOf again since first invocation
	// might return null
	writeln(String.valueOf(s));
	} else {
	synchronized (this) {
	print(s);
	newLine();
	}
	}
	}


	/**
	* A convenience method to write a formatted string to this output stream
	* using the specified format string and arguments.
	*
	* <p> An invocation of this method of the form
	* {@code out.printf(format, args)} behaves
	* in exactly the same way as the invocation
	*
	* <pre>{@code
	* out.format(format, args)
	* }</pre>
	*
	* @param format
	* A format string as described in <a
	* href="../util/Formatter.html#syntax">Format string syntax</a>
	*
	* @param args
	* Arguments referenced by the format specifiers in the format
	* string. If there are more arguments than format specifiers, the
	* extra arguments are ignored. The number of arguments is
	* variable and may be zero. The maximum number of arguments is
	* limited by the maximum dimension of a Java array as defined by
	* <cite>The Java Virtual Machine Specification</cite>.
	* The behaviour on a
	* {@code null} argument depends on the <a
	* href="../util/Formatter.html#syntax">conversion</a>.
	*
	* @throws java.util.IllegalFormatException
	* If a format string contains an illegal syntax, a format
	* specifier that is incompatible with the given arguments,
	* insufficient arguments given the format string, or other
	* illegal conditions. For specification of all possible
	* formatting errors, see the <a
	* href="../util/Formatter.html#detail">Details</a> section of the
	* formatter class specification.
	*
	* @throws NullPointerException
	* If the {@code format} is {@code null}
	*
	* @return This output stream
	*
	* @since 1.5
	*/
	public PrintStream printf(String format, Object ... args) {
	return format(format, args);
	}

	/**
	* A convenience method to write a formatted string to this output stream
	* using the specified format string and arguments.
	*
	* <p> An invocation of this method of the form
	* {@code out.printf(l, format, args)} behaves
	* in exactly the same way as the invocation
	*
	* <pre>{@code
	* out.format(l, format, args)
	* }</pre>
	*
	* @param l
	* The {@linkplain java.util.Locale locale} to apply during
	* formatting. If {@code l} is {@code null} then no localization
	* is applied.
	*
	* @param format
	* A format string as described in <a
	* href="../util/Formatter.html#syntax">Format string syntax</a>
	*
	* @param args
	* Arguments referenced by the format specifiers in the format
	* string. If there are more arguments than format specifiers, the
	* extra arguments are ignored. The number of arguments is
	* variable and may be zero. The maximum number of arguments is
	* limited by the maximum dimension of a Java array as defined by
	* <cite>The Java Virtual Machine Specification</cite>.
	* The behaviour on a
	* {@code null} argument depends on the <a
	* href="../util/Formatter.html#syntax">conversion</a>.
	*
	* @throws java.util.IllegalFormatException
	* If a format string contains an illegal syntax, a format
	* specifier that is incompatible with the given arguments,
	* insufficient arguments given the format string, or other
	* illegal conditions. For specification of all possible
	* formatting errors, see the <a
	* href="../util/Formatter.html#detail">Details</a> section of the
	* formatter class specification.
	*
	* @throws NullPointerException
	* If the {@code format} is {@code null}
	*
	* @return This output stream
	*
	* @since 1.5
	*/
	public PrintStream printf(Locale l, String format, Object ... args) {
	return format(l, format, args);
	}

	/**
	* Writes a formatted string to this output stream using the specified
	* format string and arguments.
	*
	* <p> The locale always used is the one returned by {@link
	* java.util.Locale#getDefault(Locale.Category)} with
	* {@link java.util.Locale.Category#FORMAT FORMAT} category specified,
	* regardless of any previous invocations of other formatting methods on
	* this object.
	*
	* @param format
	* A format string as described in <a
	* href="../util/Formatter.html#syntax">Format string syntax</a>
	*
	* @param args
	* Arguments referenced by the format specifiers in the format
	* string. If there are more arguments than format specifiers, the
	* extra arguments are ignored. The number of arguments is
	* variable and may be zero. The maximum number of arguments is
	* limited by the maximum dimension of a Java array as defined by
	* <cite>The Java Virtual Machine Specification</cite>.
	* The behaviour on a
	* {@code null} argument depends on the <a
	* href="../util/Formatter.html#syntax">conversion</a>.
	*
	* @throws java.util.IllegalFormatException
	* If a format string contains an illegal syntax, a format
	* specifier that is incompatible with the given arguments,
	* insufficient arguments given the format string, or other
	* illegal conditions. For specification of all possible
	* formatting errors, see the <a
	* href="../util/Formatter.html#detail">Details</a> section of the
	* formatter class specification.
	*
	* @throws NullPointerException
	* If the {@code format} is {@code null}
	*
	* @return This output stream
	*
	* @since 1.5
	*/
	public PrintStream format(String format, Object ... args) {
	try {
	synchronized (this) {
	ensureOpen();
	if ((formatter == null)
	\|\| (formatter.locale() !=
	Locale.getDefault(Locale.Category.FORMAT)))
	formatter = new Formatter((Appendable) this);
	formatter.format(Locale.getDefault(Locale.Category.FORMAT),
	format, args);
	}
	} catch (InterruptedIOException x) {
	Thread.currentThread().interrupt();
	} catch (IOException x) {
	trouble = true;
	}
	return this;
	}

	/**
	* Writes a formatted string to this output stream using the specified
	* format string and arguments.
	*
	* @param l
	* The {@linkplain java.util.Locale locale} to apply during
	* formatting. If {@code l} is {@code null} then no localization
	* is applied.
	*
	* @param format
	* A format string as described in <a
	* href="../util/Formatter.html#syntax">Format string syntax</a>
	*
	* @param args
	* Arguments referenced by the format specifiers in the format
	* string. If there are more arguments than format specifiers, the
	* extra arguments are ignored. The number of arguments is
	* variable and may be zero. The maximum number of arguments is
	* limited by the maximum dimension of a Java array as defined by
	* <cite>The Java Virtual Machine Specification</cite>.
	* The behaviour on a
	* {@code null} argument depends on the <a
	* href="../util/Formatter.html#syntax">conversion</a>.
	*
	* @throws java.util.IllegalFormatException
	* If a format string contains an illegal syntax, a format
	* specifier that is incompatible with the given arguments,
	* insufficient arguments given the format string, or other
	* illegal conditions. For specification of all possible
	* formatting errors, see the <a
	* href="../util/Formatter.html#detail">Details</a> section of the
	* formatter class specification.
	*
	* @throws NullPointerException
	* If the {@code format} is {@code null}
	*
	* @return This output stream
	*
	* @since 1.5
	*/
	public PrintStream format(Locale l, String format, Object ... args) {
	try {
	synchronized (this) {
	ensureOpen();
	if ((formatter == null)
	\|\| (formatter.locale() != l))
	formatter = new Formatter(this, l);
	formatter.format(l, format, args);
	}
	} catch (InterruptedIOException x) {
	Thread.currentThread().interrupt();
	} catch (IOException x) {
	trouble = true;
	}
	return this;
	}

	/**
	* Appends the specified character sequence to this output stream.
	*
	* <p> An invocation of this method of the form {@code out.append(csq)}
	* behaves in exactly the same way as the invocation
	*
	* <pre>{@code
	* out.print(csq.toString())
	* }</pre>
	*
	* <p> Depending on the specification of {@code toString} for the
	* character sequence {@code csq}, the entire sequence may not be
	* appended. For instance, invoking then {@code toString} method of a
	* character buffer will return a subsequence whose content depends upon
	* the buffer's position and limit.
	*
	* @param csq
	* The character sequence to append. If {@code csq} is
	* {@code null}, then the four characters {@code "null"} are
	* appended to this output stream.
	*
	* @return This output stream
	*
	* @since 1.5
	*/
	public PrintStream append(CharSequence csq) {
	print(String.valueOf(csq));
	return this;
	}

	/**
	* Appends a subsequence of the specified character sequence to this output
	* stream.
	*
	* <p> An invocation of this method of the form
	* {@code out.append(csq, start, end)} when
	* {@code csq} is not {@code null}, behaves in
	* exactly the same way as the invocation
	*
	* <pre>{@code
	* out.print(csq.subSequence(start, end).toString())
	* }</pre>
	*
	* @param csq
	* The character sequence from which a subsequence will be
	* appended. If {@code csq} is {@code null}, then characters
	* will be appended as if {@code csq} contained the four
	* characters {@code "null"}.
	*
	* @param start
	* The index of the first character in the subsequence
	*
	* @param end
	* The index of the character following the last character in the
	* subsequence
	*
	* @return This output stream
	*
	* @throws IndexOutOfBoundsException
	* If {@code start} or {@code end} are negative, {@code start}
	* is greater than {@code end}, or {@code end} is greater than
	* {@code csq.length()}
	*
	* @since 1.5
	*/
	public PrintStream append(CharSequence csq, int start, int end) {
	if (csq == null) csq = "null";
	return append(csq.subSequence(start, end));
	}

	/**
	* Appends the specified character to this output stream.
	*
	* <p> An invocation of this method of the form {@code out.append(c)}
	* behaves in exactly the same way as the invocation
	*
	* <pre>{@code
	* out.print(c)
	* }</pre>
	*
	* @param c
	* The 16-bit character to append
	*
	* @return This output stream
	*
	* @since 1.5
	*/
	public PrintStream append(char c) {
	print(c);
	return this;
	}

	}

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