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	/*
	* Copyright (c) 2003, 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.util;

	import java.io.IOException;

	/**
	* The <tt>Formattable</tt> interface must be implemented by any class that
	* needs to perform custom formatting using the <tt>'s'</tt> conversion
	* specifier of {@link java.util.Formatter}. This interface allows basic
	* control for formatting arbitrary objects.
	*
	* For example, the following class prints out different representations of a
	* stock's name depending on the flags and length constraints:
	*
	* <pre> {@code
	* import java.nio.CharBuffer;
	* import java.util.Formatter;
	* import java.util.Formattable;
	* import java.util.Locale;
	* import static java.util.FormattableFlags.*;
	*
	* ...
	*
	* public class StockName implements Formattable {
	* private String symbol, companyName, frenchCompanyName;
	* public StockName(String symbol, String companyName,
	* String frenchCompanyName) {
	* ...
	* }
	*
	* ...
	*
	* public void formatTo(Formatter fmt, int f, int width, int precision) {
	* StringBuilder sb = new StringBuilder();
	*
	* // decide form of name
	* String name = companyName;
	* if (fmt.locale().equals(Locale.FRANCE))
	* name = frenchCompanyName;
	* boolean alternate = (f & ALTERNATE) == ALTERNATE;
	* boolean usesymbol = alternate \|\| (precision != -1 && precision < 10);
	* String out = (usesymbol ? symbol : name);
	*
	* // apply precision
	* if (precision == -1 \|\| out.length() < precision) {
	* // write it all
	* sb.append(out);
	* } else {
	* sb.append(out.substring(0, precision - 1)).append('*');
	* }
	*
	* // apply width and justification
	* int len = sb.length();
	* if (len < width)
	* for (int i = 0; i < width - len; i++)
	* if ((f & LEFT_JUSTIFY) == LEFT_JUSTIFY)
	* sb.append(' ');
	* else
	* sb.insert(0, ' ');
	*
	* fmt.format(sb.toString());
	* }
	*
	* public String toString() {
	* return String.format("%s - %s", symbol, companyName);
	* }
	* }
	* }</pre>
	*
	* <p> When used in conjunction with the {@link java.util.Formatter}, the above
	* class produces the following output for various format strings.
	*
	* <pre> {@code
	* Formatter fmt = new Formatter();
	* StockName sn = new StockName("HUGE", "Huge Fruit, Inc.",
	* "Fruit Titanesque, Inc.");
	* fmt.format("%s", sn); // -> "Huge Fruit, Inc."
	* fmt.format("%s", sn.toString()); // -> "HUGE - Huge Fruit, Inc."
	* fmt.format("%#s", sn); // -> "HUGE"
	* fmt.format("%-10.8s", sn); // -> "HUGE "
	* fmt.format("%.12s", sn); // -> "Huge Fruit,*"
	* fmt.format(Locale.FRANCE, "%25s", sn); // -> " Fruit Titanesque, Inc."
	* }</pre>
	*
	* <p> Formattables are not necessarily safe for multithreaded access. Thread
	* safety is optional and may be enforced by classes that extend and implement
	* this interface.
	*
	* <p> Unless otherwise specified, passing a <tt>null</tt> argument to
	* any method in this interface will cause a {@link
	* NullPointerException} to be thrown.
	*
	* @since 1.5
	*/
	public interface Formattable {

	/**
	* Formats the object using the provided {@link Formatter formatter}.
	*
	* @param formatter
	* The {@link Formatter formatter}. Implementing classes may call
	* {@link Formatter#out() formatter.out()} or {@link
	* Formatter#locale() formatter.locale()} to obtain the {@link
	* Appendable} or {@link Locale} used by this
	* <tt>formatter</tt> respectively.
	*
	* @param flags
	* The flags modify the output format. The value is interpreted as
	* a bitmask. Any combination of the following flags may be set:
	* {@link FormattableFlags#LEFT_JUSTIFY}, {@link
	* FormattableFlags#UPPERCASE}, and {@link
	* FormattableFlags#ALTERNATE}. If no flags are set, the default
	* formatting of the implementing class will apply.
	*
	* @param width
	* The minimum number of characters to be written to the output.
	* If the length of the converted value is less than the
	* <tt>width</tt> then the output will be padded by
	* <tt>'  '</tt> until the total number of characters
	* equals width. The padding is at the beginning by default. If
	* the {@link FormattableFlags#LEFT_JUSTIFY} flag is set then the
	* padding will be at the end. If <tt>width</tt> is <tt>-1</tt>
	* then there is no minimum.
	*
	* @param precision
	* The maximum number of characters to be written to the output.
	* The precision is applied before the width, thus the output will
	* be truncated to <tt>precision</tt> characters even if the
	* <tt>width</tt> is greater than the <tt>precision</tt>. If
	* <tt>precision</tt> is <tt>-1</tt> then there is no explicit
	* limit on the number of characters.
	*
	* @throws IllegalFormatException
	* If any of the parameters are invalid. For specification of all
	* possible formatting errors, see the <a
	* href="../util/Formatter.html#detail">Details</a> section of the
	* formatter class specification.
	*/
	void formatTo(Formatter formatter, int flags, int width, int precision);
	}

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