/*
 * Copyright (c) 2013, Oracle and/or its affiliates. All rights reserved.
 *
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 * modification, are permitted provided that the following conditions
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 *
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 *     notice, this list of conditions and the following disclaimer.
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 *   - Redistributions in binary form must reproduce the above copyright
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 *     documentation and/or other materials provided with the distribution.
 *
 *   - Neither the name of Oracle or the names of its
 *     contributors may be used to endorse or promote products derived
 *     from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
 * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
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 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT OWNER OR
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import java.time.LocalDate;
import java.time.DayOfWeek;
import java.time.DateTimeException;

import java.time.temporal.Temporal;
import java.time.temporal.TemporalAdjuster;
import java.time.temporal.TemporalAdjusters;

import java.io.PrintStream;

/**
 * This temporal adjuster assumes that payday occurs on the 15th
 * and the last day of each month. However, if either of those
 * days lands on a weekend, then the previous Friday is used.
 */
public class PaydayAdjuster implements TemporalAdjuster {
    
    /**
     * The adjustInto method accepts a Temporal instance
     * and returns an adjusted LocalDate. If the passed in
     * parameter is not a LocalDate, then a DateTimeException is thrown.
     */
    public Temporal adjustInto(Temporal input) {
        LocalDate date = LocalDate.from(input);
        int day;
        if (date.getDayOfMonth() < 15) {
            day = 15;
        } else {
            day = date.with(TemporalAdjusters.lastDayOfMonth()).getDayOfMonth();
        }
        date = date.withDayOfMonth(day);
        if (date.getDayOfWeek() == DayOfWeek.SATURDAY ||
            date.getDayOfWeek() == DayOfWeek.SUNDAY) {
            date = date.with(TemporalAdjusters.previous(DayOfWeek.FRIDAY));
        }

        return input.with(date);
    }
}