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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;

	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</code> 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</code> never throws an
	* <code>IOException</code>; instead, exceptional situations merely set an
	* internal flag that can be tested via the <code>checkError</code> method.
	* Optionally, a <code>PrintStream</code> can be created so as to flush
	* automatically; this means that the <code>flush</code> method is
	* automatically invoked after a byte array is written, one of the
	* <code>println</code> methods is invoked, or a newline character or byte
	* (<code>'\n'</code>) is written.
	*
	* <p> All characters printed by a <code>PrintStream</code> are converted into
	* bytes using the platform's default character encoding. The <code>{@link
	* PrintWriter}</code> class should be used in situations that require writing
	* characters rather than bytes.
	*
	* @author Frank Yellin
	* @author Mark Reinhold
	* @since JDK1.0
	*/

	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);
	}

	private PrintStream(boolean autoFlush, OutputStream out, Charset charset) {
	super(out);
	this.autoFlush = autoFlush;
	this.charOut = new OutputStreamWriter(this, charset);
	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)
	throws UnsupportedEncodingException
	{
	this(autoFlush, out, charset);
	}

	/**
	* Creates a new print stream. This stream will not flush automatically.
	*
	* @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.
	*
	* @param out The output stream to which values and objects will be
	* printed
	* @param autoFlush A boolean; if true, the output buffer will be flushed
	* whenever a byte array is written, one of the
	* <code>println</code> methods is invoked, or a newline
	* character or byte (<code>'\n'</code>) 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.
	*
	* @param out The output stream to which values and objects will be
	* printed
	* @param autoFlush A boolean; if true, the output buffer will be flushed
	* whenever a byte array is written, one of the
	* <code>println</code> methods is invoked, or a newline
	* character or byte (<code>'\n'</code>) 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(autoFlush,
	requireNonNull(out, "Null output stream"),
	toCharset(encoding));
	}

	/**
	* 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. 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));
	}

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

	/**
	* Sets the error state of the stream to <code>true</code>.
	*
	* <p> This method will cause subsequent invocations of {@link
	* #checkError()} to return <tt>true</tt> until {@link
	* #clearError()} is invoked.
	*
	* @since JDK1.1
	*/
	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 <tt>false</tt> 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</code> method will be
	* invoked.
	*
	* <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)</code> or <code>println(char)</code>
	* methods.
	*
	* @param b The byte to be written
	* @see #print(char)
	* @see #println(char)
	*/
	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</code> bytes from the specified byte array starting at
	* offset <code>off</code> to this stream. If automatic flushing is
	* enabled then the <code>flush</code> 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)</code> or <code>println(char)</code>
	* methods.
	*
	* @param buf A byte array
	* @param off Offset from which to start taking bytes
	* @param len Number of bytes to write
	*/
	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;
	}
	}

	/*
	* 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();
	}
	}
	}
	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;
	}
	}

	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 <code>{@link
	* java.lang.String#valueOf(boolean)}</code> is translated into bytes
	* according to the platform's default character encoding, and these bytes
	* are written in exactly the manner of the
	* <code>{@link #write(int)}</code> method.
	*
	* @param b The <code>boolean</code> to be printed
	*/
	public void print(boolean b) {
	write(b ? "true" : "false");
	}

	/**
	* Prints a character. The character is translated into one or more bytes
	* according to the platform's default character encoding, and these bytes
	* are written in exactly the manner of the
	* <code>{@link #write(int)}</code> method.
	*
	* @param c The <code>char</code> to be printed
	*/
	public void print(char c) {
	write(String.valueOf(c));
	}

	/**
	* Prints an integer. The string produced by <code>{@link
	* java.lang.String#valueOf(int)}</code> is translated into bytes
	* according to the platform's default character encoding, and these bytes
	* are written in exactly the manner of the
	* <code>{@link #write(int)}</code> method.
	*
	* @param i The <code>int</code> 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 <code>{@link
	* java.lang.String#valueOf(long)}</code> is translated into bytes
	* according to the platform's default character encoding, and these bytes
	* are written in exactly the manner of the
	* <code>{@link #write(int)}</code> method.
	*
	* @param l The <code>long</code> 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 <code>{@link
	* java.lang.String#valueOf(float)}</code> is translated into bytes
	* according to the platform's default character encoding, and these bytes
	* are written in exactly the manner of the
	* <code>{@link #write(int)}</code> method.
	*
	* @param f The <code>float</code> 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
	* <code>{@link java.lang.String#valueOf(double)}</code> is translated into
	* bytes according to the platform's default character encoding, and these
	* bytes are written in exactly the manner of the <code>{@link
	* #write(int)}</code> method.
	*
	* @param d The <code>double</code> 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 platform's default character encoding, and these bytes
	* are written in exactly the manner of the
	* <code>{@link #write(int)}</code> method.
	*
	* @param s The array of chars to be printed
	*
	* @throws NullPointerException If <code>s</code> is <code>null</code>
	*/
	public void print(char s[]) {
	write(s);
	}

	/**
	* Prints a string. If the argument is <code>null</code> then the string
	* <code>"null"</code> is printed. Otherwise, the string's characters are
	* converted into bytes according to the platform's default character
	* encoding, and these bytes are written in exactly the manner of the
	* <code>{@link #write(int)}</code> method.
	*
	* @param s The <code>String</code> to be printed
	*/
	public void print(String s) {
	if (s == null) {
	s = "null";
	}
	write(s);
	}

	/**
	* Prints an object. The string produced by the <code>{@link
	* java.lang.String#valueOf(Object)}</code> method is translated into bytes
	* according to the platform's default character encoding, and these bytes
	* are written in exactly the manner of the
	* <code>{@link #write(int)}</code> method.
	*
	* @param obj The <code>Object</code> 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</code>, and is not necessarily a single newline
	* character (<code>'\n'</code>).
	*/
	public void println() {
	newLine();
	}

	/**
	* Prints a boolean and then terminate the line. This method behaves as
	* though it invokes <code>{@link #print(boolean)}</code> and then
	* <code>{@link #println()}</code>.
	*
	* @param x The <code>boolean</code> to be printed
	*/
	public void println(boolean x) {
	synchronized (this) {
	print(x);
	newLine();
	}
	}

	/**
	* Prints a character and then terminate the line. This method behaves as
	* though it invokes <code>{@link #print(char)}</code> and then
	* <code>{@link #println()}</code>.
	*
	* @param x The <code>char</code> to be printed.
	*/
	public void println(char x) {
	synchronized (this) {
	print(x);
	newLine();
	}
	}

	/**
	* Prints an integer and then terminate the line. This method behaves as
	* though it invokes <code>{@link #print(int)}</code> and then
	* <code>{@link #println()}</code>.
	*
	* @param x The <code>int</code> to be printed.
	*/
	public void println(int x) {
	synchronized (this) {
	print(x);
	newLine();
	}
	}

	/**
	* Prints a long and then terminate the line. This method behaves as
	* though it invokes <code>{@link #print(long)}</code> and then
	* <code>{@link #println()}</code>.
	*
	* @param x a The <code>long</code> to be printed.
	*/
	public void println(long x) {
	synchronized (this) {
	print(x);
	newLine();
	}
	}

	/**
	* Prints a float and then terminate the line. This method behaves as
	* though it invokes <code>{@link #print(float)}</code> and then
	* <code>{@link #println()}</code>.
	*
	* @param x The <code>float</code> to be printed.
	*/
	public void println(float x) {
	synchronized (this) {
	print(x);
	newLine();
	}
	}

	/**
	* Prints a double and then terminate the line. This method behaves as
	* though it invokes <code>{@link #print(double)}</code> and then
	* <code>{@link #println()}</code>.
	*
	* @param x The <code>double</code> to be printed.
	*/
	public void println(double x) {
	synchronized (this) {
	print(x);
	newLine();
	}
	}

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

	/**
	* Prints a String and then terminate the line. This method behaves as
	* though it invokes <code>{@link #print(String)}</code> and then
	* <code>{@link #println()}</code>.
	*
	* @param x The <code>String</code> to be printed.
	*/
	public void println(String x) {
	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 <code>{@link #print(String)}</code> and then
	* <code>{@link #println()}</code>.
	*
	* @param x The <code>Object</code> to be printed.
	*/
	public void println(Object x) {
	String s = String.valueOf(x);
	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 <tt>out.printf(format,
	* args)</tt> behaves in exactly the same way as the invocation
	*
	* <pre>
	* 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
	* <tt>null</tt> 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 <tt>format</tt> is <tt>null</tt>
	*
	* @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 <tt>out.printf(l, format,
	* args)</tt> behaves in exactly the same way as the invocation
	*
	* <pre>
	* out.format(l, format, args) </pre>
	*
	* @param l
	* The {@linkplain java.util.Locale locale} to apply during
	* formatting. If <tt>l</tt> is <tt>null</tt> 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
	* <tt>null</tt> 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 <tt>format</tt> is <tt>null</tt>
	*
	* @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.getDefault()}, 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
	* <tt>null</tt> 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 <tt>format</tt> is <tt>null</tt>
	*
	* @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()))
	formatter = new Formatter((Appendable) this);
	formatter.format(Locale.getDefault(), 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 <tt>l</tt> is <tt>null</tt> 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
	* <tt>null</tt> 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 <tt>format</tt> is <tt>null</tt>
	*
	* @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 <tt>out.append(csq)</tt>
	* behaves in exactly the same way as the invocation
	*
	* <pre>
	* out.print(csq.toString()) </pre>
	*
	* <p> Depending on the specification of <tt>toString</tt> for the
	* character sequence <tt>csq</tt>, the entire sequence may not be
	* appended. For instance, invoking then <tt>toString</tt> 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 <tt>csq</tt> is
	* <tt>null</tt>, then the four characters <tt>"null"</tt> are
	* appended to this output stream.
	*
	* @return This output stream
	*
	* @since 1.5
	*/
	public PrintStream append(CharSequence csq) {
	if (csq == null)
	print("null");
	else
	print(csq.toString());
	return this;
	}

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

	/**
	* Appends the specified character to this output stream.
	*
	* <p> An invocation of this method of the form <tt>out.append(c)</tt>
	* behaves in exactly the same way as the invocation
	*
	* <pre>
	* 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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