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	/*
	* Copyright (c) 1996, 2012, 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.Objects;
	import java.util.Formatter;
	import java.util.Locale;
	import java.nio.charset.Charset;
	import java.nio.charset.IllegalCharsetNameException;
	import java.nio.charset.UnsupportedCharsetException;

	/**
	* Prints formatted representations of objects to a text-output stream. This
	* class implements all of the <tt>print</tt> methods found in {@link
	* PrintStream}. It does not contain methods for writing raw bytes, for which
	* a program should use unencoded byte streams.
	*
	* <p> Unlike the {@link PrintStream} class, if automatic flushing is enabled
	* it will be done only when one of the <tt>println</tt>, <tt>printf</tt>, or
	* <tt>format</tt> methods is invoked, rather than whenever a newline character
	* happens to be output. These methods use the platform's own notion of line
	* separator rather than the newline character.
	*
	* <p> Methods in this class never throw I/O exceptions, although some of its
	* constructors may. The client may inquire as to whether any errors have
	* occurred by invoking {@link #checkError checkError()}.
	*
	* @author Frank Yellin
	* @author Mark Reinhold
	* @since JDK1.1
	*/

	public class PrintWriter extends Writer {

	/**
	* The underlying character-output stream of this
	* <code>PrintWriter</code>.
	*
	* @since 1.2
	*/
	protected Writer out;

	private final boolean autoFlush;
	private boolean trouble = false;
	private Formatter formatter;
	private PrintStream psOut = null;

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

	/**
	* 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
	{
	Objects.requireNonNull(csn, "charsetName");
	try {
	return Charset.forName(csn);
	} catch (IllegalCharsetNameException\|UnsupportedCharsetException unused) {
	// UnsupportedEncodingException should be thrown
	throw new UnsupportedEncodingException(csn);
	}
	}

	/**
	* Creates a new PrintWriter, without automatic line flushing.
	*
	* @param out A character-output stream
	*/
	public PrintWriter (Writer out) {
	this(out, false);
	}

	/**
	* Creates a new PrintWriter.
	*
	* @param out A character-output stream
	* @param autoFlush A boolean; if true, the <tt>println</tt>,
	* <tt>printf</tt>, or <tt>format</tt> methods will
	* flush the output buffer
	*/
	public PrintWriter(Writer out,
	boolean autoFlush) {
	super(out);
	this.out = out;
	this.autoFlush = autoFlush;
	lineSeparator = java.security.AccessController.doPrivileged(
	new sun.security.action.GetPropertyAction("line.separator"));
	}

	/**
	* Creates a new PrintWriter, without automatic line flushing, from an
	* existing OutputStream. This convenience constructor creates the
	* necessary intermediate OutputStreamWriter, which will convert characters
	* into bytes using the default character encoding.
	*
	* @param out An output stream
	*
	* @see java.io.OutputStreamWriter#OutputStreamWriter(java.io.OutputStream)
	*/
	public PrintWriter(OutputStream out) {
	this(out, false);
	}

	/**
	* Creates a new PrintWriter from an existing OutputStream. This
	* convenience constructor creates the necessary intermediate
	* OutputStreamWriter, which will convert characters into bytes using the
	* default character encoding.
	*
	* @param out An output stream
	* @param autoFlush A boolean; if true, the <tt>println</tt>,
	* <tt>printf</tt>, or <tt>format</tt> methods will
	* flush the output buffer
	*
	* @see java.io.OutputStreamWriter#OutputStreamWriter(java.io.OutputStream)
	*/
	public PrintWriter(OutputStream out, boolean autoFlush) {
	this(new BufferedWriter(new OutputStreamWriter(out)), autoFlush);

	// save print stream for error propagation
	if (out instanceof java.io.PrintStream) {
	psOut = (PrintStream) out;
	}
	}

	/**
	* Creates a new PrintWriter, 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 writer.
	* 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 string 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 PrintWriter(String fileName) throws FileNotFoundException {
	this(new BufferedWriter(new OutputStreamWriter(new FileOutputStream(fileName))),
	false);
	}

	/* Private constructor */
	private PrintWriter(Charset charset, File file)
	throws FileNotFoundException
	{
	this(new BufferedWriter(new OutputStreamWriter(new FileOutputStream(file), charset)),
	false);
	}

	/**
	* Creates a new PrintWriter, 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 writer.
	* 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 string 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 PrintWriter(String fileName, String csn)
	throws FileNotFoundException, UnsupportedEncodingException
	{
	this(toCharset(csn), new File(fileName));
	}

	/**
	* Creates a new PrintWriter, 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 writer. 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 PrintWriter(File file) throws FileNotFoundException {
	this(new BufferedWriter(new OutputStreamWriter(new FileOutputStream(file))),
	false);
	}

	/**
	* Creates a new PrintWriter, 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 writer. 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 PrintWriter(File file, String csn)
	throws FileNotFoundException, UnsupportedEncodingException
	{
	this(toCharset(csn), file);
	}

	/** 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 stream.
	* @see #checkError()
	*/
	public void flush() {
	try {
	synchronized (lock) {
	ensureOpen();
	out.flush();
	}
	}
	catch (IOException x) {
	trouble = true;
	}
	}

	/**
	* Closes the stream and releases any system resources associated
	* with it. Closing a previously closed stream has no effect.
	*
	* @see #checkError()
	*/
	public void close() {
	try {
	synchronized (lock) {
	if (out == null)
	return;
	out.close();
	out = null;
	}
	}
	catch (IOException x) {
	trouble = true;
	}
	}

	/**
	* Flushes the stream if it's not closed and checks its error state.
	*
	* @return <code>true</code> if the print stream has encountered an error,
	* either on the underlying output stream or during a format
	* conversion.
	*/
	public boolean checkError() {
	if (out != null) {
	flush();
	}
	if (out instanceof java.io.PrintWriter) {
	PrintWriter pw = (PrintWriter) out;
	return pw.checkError();
	} else if (psOut != null) {
	return psOut.checkError();
	}
	return trouble;
	}

	/**
	* Indicates that an error has occurred.
	*
	* <p> This method will cause subsequent invocations of {@link
	* #checkError()} to return <tt>true</tt> until {@link
	* #clearError()} is invoked.
	*/
	protected void setError() {
	trouble = true;
	}

	/**
	* Clears the 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 Writer
	*/

	/**
	* Writes a single character.
	* @param c int specifying a character to be written.
	*/
	public void write(int c) {
	try {
	synchronized (lock) {
	ensureOpen();
	out.write(c);
	}
	}
	catch (InterruptedIOException x) {
	Thread.currentThread().interrupt();
	}
	catch (IOException x) {
	trouble = true;
	}
	}

	/**
	* Writes A Portion of an array of characters.
	* @param buf Array of characters
	* @param off Offset from which to start writing characters
	* @param len Number of characters to write
	*/
	public void write(char buf[], int off, int len) {
	try {
	synchronized (lock) {
	ensureOpen();
	out.write(buf, off, len);
	}
	}
	catch (InterruptedIOException x) {
	Thread.currentThread().interrupt();
	}
	catch (IOException x) {
	trouble = true;
	}
	}

	/**
	* Writes an array of characters. This method cannot be inherited from the
	* Writer class because it must suppress I/O exceptions.
	* @param buf Array of characters to be written
	*/
	public void write(char buf[]) {
	write(buf, 0, buf.length);
	}

	/**
	* Writes a portion of a string.
	* @param s A String
	* @param off Offset from which to start writing characters
	* @param len Number of characters to write
	*/
	public void write(String s, int off, int len) {
	try {
	synchronized (lock) {
	ensureOpen();
	out.write(s, off, len);
	}
	}
	catch (InterruptedIOException x) {
	Thread.currentThread().interrupt();
	}
	catch (IOException x) {
	trouble = true;
	}
	}

	/**
	* Writes a string. This method cannot be inherited from the Writer class
	* because it must suppress I/O exceptions.
	* @param s String to be written
	*/
	public void write(String s) {
	write(s, 0, s.length());
	}

	private void newLine() {
	try {
	synchronized (lock) {
	ensureOpen();
	out.write(lineSeparator);
	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(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 value and then terminates 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> value to be printed
	*/
	public void println(boolean x) {
	synchronized (lock) {
	print(x);
	println();
	}
	}

	/**
	* Prints a character and then terminates 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> value to be printed
	*/
	public void println(char x) {
	synchronized (lock) {
	print(x);
	println();
	}
	}

	/**
	* Prints an integer and then terminates 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> value to be printed
	*/
	public void println(int x) {
	synchronized (lock) {
	print(x);
	println();
	}
	}

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

	/**
	* Prints a floating-point number and then terminates 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> value to be printed
	*/
	public void println(float x) {
	synchronized (lock) {
	print(x);
	println();
	}
	}

	/**
	* Prints a double-precision floating-point number and then terminates 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> value to be printed
	*/
	public void println(double x) {
	synchronized (lock) {
	print(x);
	println();
	}
	}

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

	/**
	* Prints a String and then terminates 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> value to be printed
	*/
	public void println(String x) {
	synchronized (lock) {
	print(x);
	println();
	}
	}

	/**
	* Prints an Object and then terminates 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 (lock) {
	print(s);
	println();
	}
	}

	/**
	* A convenience method to write a formatted string to this writer using
	* the specified format string and arguments. If automatic flushing is
	* enabled, calls to this method will flush the output buffer.
	*
	* <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 writer
	*
	* @since 1.5
	*/
	public PrintWriter printf(String format, Object ... args) {
	return format(format, args);
	}

	/**
	* A convenience method to write a formatted string to this writer using
	* the specified format string and arguments. If automatic flushing is
	* enabled, calls to this method will flush the output buffer.
	*
	* <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 writer
	*
	* @since 1.5
	*/
	public PrintWriter printf(Locale l, String format, Object ... args) {
	return format(l, format, args);
	}

	/**
	* Writes a formatted string to this writer using the specified format
	* string and arguments. If automatic flushing is enabled, calls to this
	* method will flush the output buffer.
	*
	* <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 writer
	*
	* @since 1.5
	*/
	public PrintWriter format(String format, Object ... args) {
	try {
	synchronized (lock) {
	ensureOpen();
	if ((formatter == null)
	\|\| (formatter.locale() != Locale.getDefault()))
	formatter = new Formatter(this);
	formatter.format(Locale.getDefault(), format, args);
	if (autoFlush)
	out.flush();
	}
	} catch (InterruptedIOException x) {
	Thread.currentThread().interrupt();
	} catch (IOException x) {
	trouble = true;
	}
	return this;
	}

	/**
	* Writes a formatted string to this writer using the specified format
	* string and arguments. If automatic flushing is enabled, calls to this
	* method will flush the output buffer.
	*
	* @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 writer
	*
	* @since 1.5
	*/
	public PrintWriter format(Locale l, String format, Object ... args) {
	try {
	synchronized (lock) {
	ensureOpen();
	if ((formatter == null) \|\| (formatter.locale() != l))
	formatter = new Formatter(this, l);
	formatter.format(l, format, args);
	if (autoFlush)
	out.flush();
	}
	} catch (InterruptedIOException x) {
	Thread.currentThread().interrupt();
	} catch (IOException x) {
	trouble = true;
	}
	return this;
	}

	/**
	* Appends the specified character sequence to this writer.
	*
	* <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.write(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 the <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 writer.
	*
	* @return This writer
	*
	* @since 1.5
	*/
	public PrintWriter append(CharSequence csq) {
	if (csq == null)
	write("null");
	else
	write(csq.toString());
	return this;
	}

	/**
	* Appends a subsequence of the specified character sequence to this writer.
	*
	* <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.write(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 writer
	*
	* @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 PrintWriter 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 writer.
	*
	* <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.write(c) </pre>
	*
	* @param c
	* The 16-bit character to append
	*
	* @return This writer
	*
	* @since 1.5
	*/
	public PrintWriter append(char c) {
	write(c);
	return this;
	}
	}

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