jfreechart example source code file (RelativeDateFormat.java)

This example jfreechart source code file (RelativeDateFormat.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Java - jfreechart tags/keywords

decimalformat, gregoriancalendar, illegalargumentexception, illegalargumentexception, milliseconds_in_one_day, milliseconds_in_one_hour, null, null, numberformat, relativedateformat, relativedateformat, string, string, stringbuffer, text, util

The jfreechart RelativeDateFormat.java source code

/* ===========================================================
 * JFreeChart : a free chart library for the Java(tm) platform
 * ===========================================================
 *
 * (C) Copyright 2000-2008, by Object Refinery Limited and Contributors.
 *
 * Project Info:  http://www.jfree.org/jfreechart/index.html
 *
 * This library is free software; you can redistribute it and/or modify it
 * under the terms of the GNU Lesser General Public License as published by
 * the Free Software Foundation; either version 2.1 of the License, or
 * (at your option) any later version.
 *
 * This library 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 Lesser General Public
 * License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301,
 * USA.
 *
 * [Java is a trademark or registered trademark of Sun Microsystems, Inc.
 * in the United States and other countries.]
 *
 * -----------------------
 * RelativeDateFormat.java
 * -----------------------
 * (C) Copyright 2006-2008, by Object Refinery Limited and Contributors.
 *
 * Original Author:  David Gilbert (for Object Refinery Limited);
 * Contributor(s):   Michael Siemer;
 *
 * Changes:
 * --------
 * 01-Nov-2006 : Version 1 (DG);
 * 23-Nov-2006 : Added argument checks, updated equals(), added clone() and
 *               hashCode() (DG);
 * 15-Feb-2008 : Applied patch 1873328 by Michael Siemer, with minor
 *               modifications (DG);
 * 01-Sep-2008 : Added new fields for hour and minute formatting, based on
 *               patch 2033092 (DG);
 *
 */

package org.jfree.chart.util;

import java.text.DateFormat;
import java.text.DecimalFormat;
import java.text.FieldPosition;
import java.text.NumberFormat;
import java.text.ParsePosition;
import java.util.Calendar;
import java.util.Date;
import java.util.GregorianCalendar;

/**
 * A formatter that formats dates to show the elapsed time relative to some
 * base date.
 *
 * @since 1.0.3
 */
public class RelativeDateFormat extends DateFormat {

    /** The base milliseconds for the elapsed time calculation. */
    private long baseMillis;

    /**
     * A flag that controls whether or not a zero day count is displayed.
     */
    private boolean showZeroDays;

    /**
     * A flag that controls whether or not a zero hour count is displayed.
     *
     * @since 1.0.10
     */
    private boolean showZeroHours;

    /**
     * A formatter for the day count (most likely not critical until the
     * day count exceeds 999).
     */
    private NumberFormat dayFormatter;

    /**
     * A prefix prepended to the start of the format if the relative date is
     * positive.
     *
     * @since 1.0.10
     */
    private String positivePrefix;

    /**
     * A string appended after the day count.
     */
    private String daySuffix;

    /**
     * A formatter for the hours.
     *
     * @since 1.0.11
     */
    private NumberFormat hourFormatter;

    /**
     * A string appended after the hours.
     */
    private String hourSuffix;

    /**
     * A formatter for the minutes.
     *
     * @since 1.0.11
     */
    private NumberFormat minuteFormatter;

    /**
     * A string appended after the minutes.
     */
    private String minuteSuffix;

    /**
     * A formatter for the seconds (and milliseconds).
     */
    private NumberFormat secondFormatter;

    /**
     * A string appended after the seconds.
     */
    private String secondSuffix;

    /**
     * A constant for the number of milliseconds in one hour.
     */
    private static long MILLISECONDS_IN_ONE_HOUR = 60 * 60 * 1000L;

    /**
     * A constant for the number of milliseconds in one day.
     */
    private static long MILLISECONDS_IN_ONE_DAY = 24 * MILLISECONDS_IN_ONE_HOUR;

    /**
     * Creates a new instance with base milliseconds set to zero.
     */
    public RelativeDateFormat() {
        this(0L);
    }

    /**
     * Creates a new instance.
     *
     * @param time  the date/time (<code>null not permitted).
     */
    public RelativeDateFormat(Date time) {
        this(time.getTime());
    }

    /**
     * Creates a new instance.
     *
     * @param baseMillis  the time zone (<code>null not permitted).
     */
    public RelativeDateFormat(long baseMillis) {
        super();
        this.baseMillis = baseMillis;
        this.showZeroDays = false;
        this.showZeroHours = true;
        this.positivePrefix = "";
        this.dayFormatter = NumberFormat.getNumberInstance();
        this.daySuffix = "d";
        this.hourFormatter = NumberFormat.getNumberInstance();
        this.hourSuffix = "h";
        this.minuteFormatter = NumberFormat.getNumberInstance();
        this.minuteSuffix = "m";
        this.secondFormatter = NumberFormat.getNumberInstance();
        this.secondFormatter.setMaximumFractionDigits(3);
        this.secondFormatter.setMinimumFractionDigits(3);
        this.secondSuffix = "s";

        // we don't use the calendar or numberFormat fields, but equals(Object)
        // is failing without them being non-null
        this.calendar = new GregorianCalendar();
        this.numberFormat = new DecimalFormat("0");
    }

    /**
     * Returns the base date/time used to calculate the elapsed time for
     * display.
     *
     * @return The base date/time in milliseconds since 1-Jan-1970.
     *
     * @see #setBaseMillis(long)
     */
    public long getBaseMillis() {
        return this.baseMillis;
    }

    /**
     * Sets the base date/time used to calculate the elapsed time for display.
     * This should be specified in milliseconds using the same encoding as
     * <code>java.util.Date.
     *
     * @param baseMillis  the base date/time in milliseconds.
     *
     * @see #getBaseMillis()
     */
    public void setBaseMillis(long baseMillis) {
        this.baseMillis = baseMillis;
    }

    /**
     * Returns the flag that controls whether or not zero day counts are
     * shown in the formatted output.
     *
     * @return The flag.
     *
     * @see #setShowZeroDays(boolean)
     */
    public boolean getShowZeroDays() {
        return this.showZeroDays;
    }

    /**
     * Sets the flag that controls whether or not zero day counts are shown
     * in the formatted output.
     *
     * @param show  the flag.
     *
     * @see #getShowZeroDays()
     */
    public void setShowZeroDays(boolean show) {
        this.showZeroDays = show;
    }

    /**
     * Returns the flag that controls whether or not zero hour counts are
     * shown in the formatted output.
     *
     * @return The flag.
     *
     * @see #setShowZeroHours(boolean)
     *
     * @since 1.0.10
     */
    public boolean getShowZeroHours() {
        return this.showZeroHours;
    }

    /**
     * Sets the flag that controls whether or not zero hour counts are shown
     * in the formatted output.
     *
     * @param show  the flag.
     *
     * @see #getShowZeroHours()
     *
     * @since 1.0.10
     */
    public void setShowZeroHours(boolean show) {
        this.showZeroHours = show;
    }

    /**
     * Returns the string that is prepended to the format if the relative time
     * is positive.
     *
     * @return The string (never <code>null).
     *
     * @see #setPositivePrefix(String)
     *
     * @since 1.0.10
     */
    public String getPositivePrefix() {
        return this.positivePrefix;
    }

    /**
     * Sets the string that is prepended to the format if the relative time is
     * positive.
     *
     * @param prefix  the prefix (<code>null not permitted).
     *
     * @see #getPositivePrefix()
     *
     * @since 1.0.10
     */
    public void setPositivePrefix(String prefix) {
        if (prefix == null) {
            throw new IllegalArgumentException("Null 'prefix' argument.");
        }
        this.positivePrefix = prefix;
    }

    /**
     * Sets the formatter for the days.
     *
     * @param formatter  the formatter (<code>null not permitted).
     *
     * @since 1.0.11
     */
    public void setDayFormatter(NumberFormat formatter) {
        if (formatter == null) {
            throw new IllegalArgumentException("Null 'formatter' argument.");
        }
        this.dayFormatter = formatter;
    }

    /**
     * Returns the string that is appended to the day count.
     *
     * @return The string.
     *
     * @see #setDaySuffix(String)
     */
    public String getDaySuffix() {
        return this.daySuffix;
    }

    /**
     * Sets the string that is appended to the day count.
     *
     * @param suffix  the suffix (<code>null not permitted).
     *
     * @see #getDaySuffix()
     */
    public void setDaySuffix(String suffix) {
        if (suffix == null) {
            throw new IllegalArgumentException("Null 'suffix' argument.");
        }
        this.daySuffix = suffix;
    }

    /**
     * Sets the formatter for the hours.
     *
     * @param formatter  the formatter (<code>null not permitted).
     *
     * @since 1.0.11
     */
    public void setHourFormatter(NumberFormat formatter) {
        if (formatter == null) {
            throw new IllegalArgumentException("Null 'formatter' argument.");
        }
        this.hourFormatter = formatter;
    }

    /**
     * Returns the string that is appended to the hour count.
     *
     * @return The string.
     *
     * @see #setHourSuffix(String)
     */
    public String getHourSuffix() {
        return this.hourSuffix;
    }

    /**
     * Sets the string that is appended to the hour count.
     *
     * @param suffix  the suffix (<code>null not permitted).
     *
     * @see #getHourSuffix()
     */
    public void setHourSuffix(String suffix) {
        if (suffix == null) {
            throw new IllegalArgumentException("Null 'suffix' argument.");
        }
        this.hourSuffix = suffix;
    }

    /**
     * Sets the formatter for the minutes.
     *
     * @param formatter  the formatter (<code>null not permitted).
     *
     * @since 1.0.11
     */
    public void setMinuteFormatter(NumberFormat formatter) {
        if (formatter == null) {
            throw new IllegalArgumentException("Null 'formatter' argument.");
        }
        this.minuteFormatter = formatter;
    }

    /**
     * Returns the string that is appended to the minute count.
     *
     * @return The string.
     *
     * @see #setMinuteSuffix(String)
     */
    public String getMinuteSuffix() {
        return this.minuteSuffix;
    }

    /**
     * Sets the string that is appended to the minute count.
     *
     * @param suffix  the suffix (<code>null not permitted).
     *
     * @see #getMinuteSuffix()
     */
    public void setMinuteSuffix(String suffix) {
        if (suffix == null) {
            throw new IllegalArgumentException("Null 'suffix' argument.");
        }
        this.minuteSuffix = suffix;
    }

    /**
     * Returns the string that is appended to the second count.
     *
     * @return The string.
     *
     * @see #setSecondSuffix(String)
     */
    public String getSecondSuffix() {
        return this.secondSuffix;
    }

    /**
     * Sets the string that is appended to the second count.
     *
     * @param suffix  the suffix (<code>null not permitted).
     *
     * @see #getSecondSuffix()
     */
    public void setSecondSuffix(String suffix) {
        if (suffix == null) {
            throw new IllegalArgumentException("Null 'suffix' argument.");
        }
        this.secondSuffix = suffix;
    }

    /**
     * Sets the formatter for the seconds and milliseconds.
     *
     * @param formatter  the formatter (<code>null not permitted).
     */
    public void setSecondFormatter(NumberFormat formatter) {
        if (formatter == null) {
            throw new IllegalArgumentException("Null 'formatter' argument.");
        }
        this.secondFormatter = formatter;
    }

    /**
     * Formats the given date as the amount of elapsed time (relative to the
     * base date specified in the constructor).
     *
     * @param date  the date.
     * @param toAppendTo  the string buffer.
     * @param fieldPosition  the field position.
     *
     * @return The formatted date.
     */
    public StringBuffer format(Date date, StringBuffer toAppendTo,
                               FieldPosition fieldPosition) {
        long currentMillis = date.getTime();
        long elapsed = currentMillis - this.baseMillis;
        String signPrefix;
        if (elapsed < 0) {
            elapsed *= -1L;
            signPrefix = "-";
        }
        else {
            signPrefix = this.positivePrefix;
        }

        long days = elapsed / MILLISECONDS_IN_ONE_DAY;
        elapsed = elapsed - (days * MILLISECONDS_IN_ONE_DAY);
        long hours = elapsed / MILLISECONDS_IN_ONE_HOUR;
        elapsed = elapsed - (hours * MILLISECONDS_IN_ONE_HOUR);
        long minutes = elapsed / 60000L;
        elapsed = elapsed - (minutes * 60000L);
        double seconds = elapsed / 1000.0;

        toAppendTo.append(signPrefix);
        if (days != 0 || this.showZeroDays) {
            toAppendTo.append(this.dayFormatter.format(days) + getDaySuffix());
        }
        if (hours != 0 || this.showZeroHours) {
            toAppendTo.append(this.hourFormatter.format(hours)
                    + getHourSuffix());
        }
        toAppendTo.append(this.minuteFormatter.format(minutes)
                + getMinuteSuffix());
        toAppendTo.append(this.secondFormatter.format(seconds)
                + getSecondSuffix());
        return toAppendTo;
    }

    /**
     * Parses the given string (not implemented).
     *
     * @param source  the date string.
     * @param pos  the parse position.
     *
     * @return <code>null, as this method has not been implemented.
     */
    public Date parse(String source, ParsePosition pos) {
        return null;
    }

    /**
     * Tests this formatter for equality with an arbitrary object.
     *
     * @param obj  the object (<code>null permitted).
     *
     * @return A boolean.
     */
    public boolean equals(Object obj) {
        if (obj == this) {
            return true;
        }
        if (!(obj instanceof RelativeDateFormat)) {
            return false;
        }
        if (!super.equals(obj)) {
            return false;
        }
        RelativeDateFormat that = (RelativeDateFormat) obj;
        if (this.baseMillis != that.baseMillis) {
            return false;
        }
        if (this.showZeroDays != that.showZeroDays) {
            return false;
        }
        if (this.showZeroHours != that.showZeroHours) {
            return false;
        }
        if (!this.positivePrefix.equals(that.positivePrefix)) {
            return false;
        }
        if (!this.daySuffix.equals(that.daySuffix)) {
            return false;
        }
        if (!this.hourSuffix.equals(that.hourSuffix)) {
            return false;
        }
        if (!this.minuteSuffix.equals(that.minuteSuffix)) {
            return false;
        }
        if (!this.secondSuffix.equals(that.secondSuffix)) {
            return false;
        }
        if (!this.dayFormatter.equals(that.dayFormatter)) {
            return false;
        }
        if (!this.hourFormatter.equals(that.hourFormatter)) {
            return false;
        }
        if (!this.minuteFormatter.equals(that.minuteFormatter)) {
            return false;
        }
        if (!this.secondFormatter.equals(that.secondFormatter)) {
            return false;
        }
        return true;
    }

    /**
     * Returns a hash code for this instance.
     *
     * @return A hash code.
     */
    public int hashCode() {
        int result = 193;
        result = 37 * result
                + (int) (this.baseMillis ^ (this.baseMillis >>> 32));
        result = 37 * result + this.positivePrefix.hashCode();
        result = 37 * result + this.daySuffix.hashCode();
        result = 37 * result + this.hourSuffix.hashCode();
        result = 37 * result + this.minuteSuffix.hashCode();
        result = 37 * result + this.secondSuffix.hashCode();
        result = 37 * result + this.secondFormatter.hashCode();
        return result;
    }

    /**
     * Returns a clone of this instance.
     *
     * @return A clone.
     */
    public Object clone() {
        RelativeDateFormat clone = (RelativeDateFormat) super.clone();
        clone.dayFormatter = (NumberFormat) this.dayFormatter.clone();
        clone.secondFormatter = (NumberFormat) this.secondFormatter.clone();
        return clone;
    }

    /**
     * Some test code.
     *
     * @param args  ignored.
     */
    public static void main(String[] args) {
        GregorianCalendar c0 = new GregorianCalendar(2006, 10, 1, 0, 0, 0);
        GregorianCalendar c1 = new GregorianCalendar(2006, 10, 1, 11, 37, 43);
        c1.set(Calendar.MILLISECOND, 123);

        System.out.println("Default: ");
        RelativeDateFormat rdf = new RelativeDateFormat(c0.getTime().getTime());
        System.out.println(rdf.format(c1.getTime()));
        System.out.println();

        System.out.println("Hide milliseconds: ");
        rdf.setSecondFormatter(new DecimalFormat("0"));
        System.out.println(rdf.format(c1.getTime()));
        System.out.println();

        System.out.println("Show zero day output: ");
        rdf.setShowZeroDays(true);
        System.out.println(rdf.format(c1.getTime()));
        System.out.println();

        System.out.println("Alternative suffixes: ");
        rdf.setShowZeroDays(false);
        rdf.setDaySuffix(":");
        rdf.setHourSuffix(":");
        rdf.setMinuteSuffix(":");
        rdf.setSecondSuffix("");
        System.out.println(rdf.format(c1.getTime()));
        System.out.println();
    }
}