/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements. See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache license, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License. You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the license for the specific language governing permissions and
 * limitations under the license.
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package org.apache.logging.log4j.core.util.datetime;

import java.text.FieldPosition;
import java.util.Calendar;
import java.util.Date;
import java.util.Locale;
import java.util.TimeZone;

DatePrinter is the "missing" interface for the format methods of DateFormat. You can obtain an object implementing this interface by using one of the FastDateFormat factory methods. 

Warning: Since binary compatible methods may be added to this interface in any
release, developers are not expected to implement this interface.


Copied and modified from Apache Commons Lang.

Since:
Apache Commons Lang 3.2/**
 * DatePrinter is the "missing" interface for the format methods of
 * {@link java.text.DateFormat}. You can obtain an object implementing this
 * interface by using one of the FastDateFormat factory methods.
 * <p>
 * Warning: Since binary compatible methods may be added to this interface in any
 * release, developers are not expected to implement this interface.
 * </p>
 *
 * <p>
 * Copied and modified from <a href="https://commons.apache.org/proper/commons-lang/">Apache Commons Lang</a>.
 * </p>
 *
 * @since Apache Commons Lang 3.2
 */
public interface DatePrinter {

    
Formats a millisecond long value.
Params:
millis –  the millisecond value to format
Returns:
the formatted string
Since:
2.1/**
     * <p>Formats a millisecond {@code long} value.</p>
     *
     * @param millis  the millisecond value to format
     * @return the formatted string
     * @since 2.1
     */
    String format(long millis);

    
Formats a Date object using a GregorianCalendar.
Params:
date –  the date to format
Returns:
the formatted string/**
     * <p>Formats a {@code Date} object using a {@code GregorianCalendar}.</p>
     *
     * @param date  the date to format
     * @return the formatted string
     */
    String format(Date date);

    
Formats a Calendar object.
The TimeZone set on the Calendar is only used to adjust the time offset.
The TimeZone specified during the construction of the Parser will determine the TimeZone
used in the formatted string.
Params:
calendar –  the calendar to format.
Returns:
the formatted string/**
     * <p>Formats a {@code Calendar} object.</p>
     * The TimeZone set on the Calendar is only used to adjust the time offset.
     * The TimeZone specified during the construction of the Parser will determine the TimeZone
     * used in the formatted string.
     *
     * @param calendar  the calendar to format.
     * @return the formatted string
     */
    String format(Calendar calendar);

    
Formats a millisecond long value into the supplied Appendable.
Params:
millis –  the millisecond value to format
buf –  the buffer to format into
Type parameters:
<B> – the Appendable class type, usually StringBuilder or StringBuffer.
Returns:
the specified string buffer
Since:
3.5/**
     * <p>Formats a millisecond {@code long} value into the
     * supplied {@code Appendable}.</p>
     *
     * @param millis  the millisecond value to format
     * @param buf  the buffer to format into
     * @param <B> the Appendable class type, usually StringBuilder or StringBuffer.
     * @return the specified string buffer
     * @since 3.5
     */
    <B extends Appendable> B format(long millis, B buf);

    
Formats a Date object into the supplied Appendable using a GregorianCalendar.
Params:
date –  the date to format
buf –  the buffer to format into
Type parameters:
<B> – the Appendable class type, usually StringBuilder or StringBuffer.
Returns:
the specified string buffer
Since:
3.5/**
     * <p>Formats a {@code Date} object into the
     * supplied {@code Appendable} using a {@code GregorianCalendar}.</p>
     *
     * @param date  the date to format
     * @param buf  the buffer to format into
     * @param <B> the Appendable class type, usually StringBuilder or StringBuffer.
     * @return the specified string buffer
     * @since 3.5
     */
    <B extends Appendable> B format(Date date, B buf);

    
Formats a Calendar object into the supplied Appendable.
The TimeZone set on the Calendar is only used to adjust the time offset.
The TimeZone specified during the construction of the Parser will determine the TimeZone
used in the formatted string.
Params:
calendar –  the calendar to format
buf –  the buffer to format into
Type parameters:
<B> – the Appendable class type, usually StringBuilder or StringBuffer.
Returns:
the specified string buffer
Since:
3.5/**
     * <p>Formats a {@code Calendar} object into the supplied {@code Appendable}.</p>
     * The TimeZone set on the Calendar is only used to adjust the time offset.
     * The TimeZone specified during the construction of the Parser will determine the TimeZone
     * used in the formatted string.
     *
     * @param calendar  the calendar to format
     * @param buf  the buffer to format into
     * @param <B> the Appendable class type, usually StringBuilder or StringBuffer.
     * @return the specified string buffer
     * @since 3.5
     */
    <B extends Appendable> B format(Calendar calendar, B buf);


    // Accessors
    //-----------------------------------------------------------------------
    
Gets the pattern used by this printer.
Returns:
the pattern, SimpleDateFormat compatible/**
     * <p>Gets the pattern used by this printer.</p>
     *
     * @return the pattern, {@link java.text.SimpleDateFormat} compatible
     */
    String getPattern();

    
Gets the time zone used by this printer.
This zone is always used for Date printing. 
Returns:
the time zone/**
     * <p>Gets the time zone used by this printer.</p>
     *
     * <p>This zone is always used for {@code Date} printing. </p>
     *
     * @return the time zone
     */
    TimeZone getTimeZone();

    
Gets the locale used by this printer.
Returns:
the locale/**
     * <p>Gets the locale used by this printer.</p>
     *
     * @return the locale
     */
    Locale getLocale();

    
Formats a Date, Calendar or Long (milliseconds) object.
Params:
obj –  the object to format
toAppendTo –  the buffer to append to
pos –  the position - ignored
See Also:
DateFormat.format(Object, StringBuffer, FieldPosition)
Returns:
the buffer passed in/**
     * <p>Formats a {@code Date}, {@code Calendar} or
     * {@code Long} (milliseconds) object.</p>
     *
     * @param obj  the object to format
     * @param toAppendTo  the buffer to append to
     * @param pos  the position - ignored
     * @return the buffer passed in
     * @see java.text.DateFormat#format(Object, StringBuffer, FieldPosition)
     */
    StringBuilder format(Object obj, StringBuilder toAppendTo, FieldPosition pos);
}