Java Month Get getSpecficMonthStart(Date date, int amount)

Description

get Specfic Month Start

License

Apache License

Declaration

public static Date getSpecficMonthStart(Date date, int amount) 

Method Source Code

//package com.java2s;
//License from project: Apache License 

import java.text.SimpleDateFormat;
import java.util.Calendar;
import java.util.Date;

public class Main {
    public static SimpleDateFormat format = new SimpleDateFormat("yyyyMMdd");
    public static SimpleDateFormat format1 = new SimpleDateFormat("yyyyMMdd HH:mm:ss");

    public static Date getSpecficMonthStart(Date date, int amount) {
        Calendar cal = Calendar.getInstance();
        cal.setTime(date);/* w w w  .j a  v  a2s.co m*/
        cal.add(Calendar.MONTH, amount);
        cal.set(Calendar.DAY_OF_MONTH, 1);
        return getStartDate(cal.getTime());
    }

    /**
     * Adds to a date returning a new object.
     * The original date object is unchanged.
     *
     * @param date  the date, not null
     * @param calendarField  the calendar field to add to
     * @param amount  the amount to add, may be negative
     * @return the new date object with the amount added
     * @throws IllegalArgumentException if the date is null
     * @deprecated Will become privately scoped in 3.0
     */
    @Deprecated
    public static Date add(Date date, int calendarField, int amount) {
        if (date == null) {
            throw new IllegalArgumentException("The date must not be null");
        }
        Calendar c = Calendar.getInstance();
        c.setTime(date);
        c.add(calendarField, amount);
        return c.getTime();
    }

    public static Date add(int field, Date date, int value) {
        Calendar c = Calendar.getInstance();
        c.setTime(date);

        int fieldNewValue = (c.get(field) + value);
        c.set(field, fieldNewValue);
        return c.getTime();
    }

    /**
     * Sets the specified field to a date returning a new object.  
     * This does not use a lenient calendar.
     * The original date object is unchanged.
     *
     * @param date  the date, not null
     * @param calendarField  the calendar field to set the amount to
     * @param amount the amount to set
     * @return a new Date object set with the specified value
     * @throws IllegalArgumentException if the date is null
     * @since 2.4
     */
    private static Date set(Date date, int calendarField, int amount) {
        if (date == null) {
            throw new IllegalArgumentException("The date must not be null");
        }
        // getInstance() returns a new object, so this method is thread safe.
        Calendar c = Calendar.getInstance();
        c.setLenient(false);
        c.setTime(date);
        c.set(calendarField, amount);
        return c.getTime();
    }

    public static Date getStartDate(Date date) {
        String temp = format.format(date);
        temp += " 00:00:00";

        try {
            return format1.parse(temp);
        } catch (Exception e) {
            return null;
        }
    }

    public static String getTime(String pattern) {
        return new SimpleDateFormat(pattern).format(new Date());
    }

    public static int get(int field, Date date) {
        Calendar c = Calendar.getInstance();
        c.setTime(date);
        return c.get(field);
    }

    public static Date parse(Long time) {
        if (time == null) {
            return null;
        }
        Calendar cal = Calendar.getInstance();
        cal.setTimeInMillis(time);
        return cal.getTime();
    }
}

Related

1. getMonthStrings()
2. getNearbyMonth(String month, int i)
3. getReportMonthString()
4. getSelectMonth(String month)
5. getShortMonthForInt(final Locale locale, int theMonth)
6. getStartDateOfMonth(String yyyymm)
7. getStrOfNextMonth(String dateStr)
8. getStrThisMonth()
9. getThisMonth()