/*
* HumanTime.java
*
* Created on 06.10.2008
*
* Copyright (c) 2008 Johann Burkard (<mailto:jb@eaio.com>) <http://eaio.com>
*
* Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated
* documentation files (the "Software"), to deal in the Software without restriction, including without limitation the
* rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in all copies or substantial portions of the
* Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE
* WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
* COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
* OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*
*/
package com.eaio.util.text;
import java.io.Externalizable;
import java.io.IOException;
import java.io.ObjectInput;
import java.io.ObjectOutput;
import java.util.Iterator;
/**
* HumanTime parses and formats time deltas for easier reading by humans. It can format time information without losing
* information but its main purpose is to generate more easily understood approximations.
* <h3>Using HumanTime</h3>
* <p>
* Use HumanTime by creating an instance that contains the time delta ({@link HumanTime#HumanTime(long)}), create an
* empty instance through ({@link HumanTime#HumanTime()}) and set the delta using the {@link #y()}, {@link #d()},
* {@link #h()}, {@link #s()} and {@link #ms()} methods or parse a {@link CharSequence} representation ({@link #eval(CharSequence)}).
* Parsing ignores whitespace and is case insensitive.
* </p>
* <h3>HumanTime format</h3>
* <p>
* HumanTime will format time deltas in years ("y"), days ("d"), hours ("h"), minutes ("m"), seconds ("s") and
* milliseconds ("ms"), separated by a blank character. For approximate representations, the time delta will be round up
* or down if necessary.
* </p>
* <h3>HumanTime examples</h3>
* <ul>
* <li>HumanTime.eval("1 d 1d 2m 3m").getExactly() = "2 d 5 m"</li>
* <li>HumanTime.eval("2m8d2h4m").getExactly() = "8 d 2 h 6 m"</li>
* <li>HumanTime.approximately("2 d 8 h 20 m 50 s") = "2 d 8 h"</li>
* <li>HumanTime.approximately("55m") = "1 h"</li>
* </ul>
* <h3>Implementation details</h3>
* <ul>
* <li>The time delta can only be increased.</li>
* <li>Instances of this class are thread safe.</li>
* <li>Getters using the Java Beans naming conventions are provided for use in environments like JSP or with expression
* languages like OGNL. See {@link #getApproximately()} and {@link #getExactly()}.</li>
* <li>To keep things simple, a year consists of 365 days.</li>
* </ul>
*
* @author <a href="mailto:jb@eaio.com">Johann Burkard</a>
* @version $Id: HumanTime.java 323 2008-10-08 19:06:22Z Johann $
* @see #eval(CharSequence)
* @see #approximately(CharSequence)
* @see <a href="http://johannburkard.de/blog/programming/java/date-formatting-parsing-humans-humantime.html">Date Formatting and Parsing for Humans in Java with HumanTime</a>
*/
public class HumanTime implements Externalizable, Comparable<HumanTime>, Cloneable {
/**
* The serial version UID.
*/
private static final long serialVersionUID = 5179328390732826722L;
/**
* One second.
*/
private static final long SECOND = 1000;
/**
* One minute.
*/
private static final long MINUTE = SECOND * 60;
/**
* One hour.
*/
private static final long HOUR = MINUTE * 60;
/**
* One day.
*/
private static final long DAY = HOUR * 24;
/**
* One year.
*/
private static final long YEAR = DAY * 365;
/**
* Percentage of what is round up or down.
*/
private static final int CEILING_PERCENTAGE = 15;
/**
* Parsing state.
*/
static enum State {
NUMBER, IGNORED, UNIT
}
static State getState(char c) {
State out;
switch (c) {
case '0':
case '1':
case '2':
case '3':
case '4':
case '5':
case '6':
case '7':
case '8':
case '9':
out = State.NUMBER;
break;
case 's':
case 'm':
case 'h':
case 'd':
case 'y':
case 'S':
case 'M':
case 'H':
case 'D':
case 'Y':
out = State.UNIT;
break;
default:
out = State.IGNORED;
}
return out;
}
/**
* Parses a {@link CharSequence} argument and returns a {@link HumanTime} instance.
*
* @param s the char sequence, may not be <code>null</code>
* @return an instance, never <code>null</code>
*/
public static HumanTime eval(final CharSequence s) {
HumanTime out = new HumanTime(0L);
int num = 0;
int start = 0;
int end = 0;
State oldState = State.IGNORED;
for (char c : new Iterable<Character>() {
/**
* @see java.lang.Iterable#iterator()
*/
public Iterator<Character> iterator() {
return new Iterator<Character>() {
private int p = 0;
/**
* @see java.util.Iterator#hasNext()
*/
public boolean hasNext() {
return p < s.length();
}
/**
* @see java.util.Iterator#next()
*/
public Character next() {
return s.charAt(p++);
}
/**
* @see java.util.Iterator#remove()
*/
public void remove() {
throw new UnsupportedOperationException();
}
};
}
}) {
State newState = getState(c);
if (oldState != newState) {
if (oldState == State.NUMBER && (newState == State.IGNORED || newState == State.UNIT)) {
num = Integer.parseInt(s.subSequence(start, end).toString());
}
else if (oldState == State.UNIT && (newState == State.IGNORED || newState == State.NUMBER)) {
out.nTimes(s.subSequence(start, end).toString(), num);
num = 0;
}
start = end;
}
++end;
oldState = newState;
}
if (oldState == State.UNIT) {
out.nTimes(s.subSequence(start, end).toString(), num);
}
return out;
}
/**
* Parses and formats the given char sequence, preserving all data.
* <p>
* Equivalent to <code>eval(in).getExactly()</code>
*
* @param in the char sequence, may not be <code>null</code>
* @return a formatted String, never <code>null</code>
*/
public static String exactly(CharSequence in) {
return eval(in).getExactly();
}
/**
* Formats the given time delta, preserving all data.
* <p>
* Equivalent to <code>new HumanTime(in).getExactly()</code>
*
* @param l the time delta
* @return a formatted String, never <code>null</code>
*/
public static String exactly(long l) {
return new HumanTime(l).getExactly();
}
/**
* Parses and formats the given char sequence, potentially removing some data to make the output easier to
* understand.
* <p>
* Equivalent to <code>eval(in).getApproximately()</code>
*
* @param in the char sequence, may not be <code>null</code>
* @return a formatted String, never <code>null</code>
*/
public static String approximately(CharSequence in) {
return eval(in).getApproximately();
}
/**
* Formats the given time delta, preserving all data.
* <p>
* Equivalent to <code>new HumanTime(l).getApproximately()</code>
*
* @param l the time delta
* @return a formatted String, never <code>null</code>
*/
public static String approximately(long l) {
return new HumanTime(l).getApproximately();
}
/**
* The time delta.
*/
private long delta;
/**
* No-argument Constructor for HumanTime.
* <p>
* Equivalent to calling <code>new HumanTime(0L)</code>.
*/
public HumanTime() {
this(0L);
}
/**
* Constructor for HumanTime.
*
* @param delta the initial time delta, interpreted as a positive number
*/
public HumanTime(long delta) {
super();
this.delta = Math.abs(delta);
}
private void nTimes(String unit, int n) {
if ("ms".equalsIgnoreCase(unit)) {
ms(n);
}
else if ("s".equalsIgnoreCase(unit)) {
s(n);
}
else if ("m".equalsIgnoreCase(unit)) {
m(n);
}
else if ("h".equalsIgnoreCase(unit)) {
h(n);
}
else if ("d".equalsIgnoreCase(unit)) {
d(n);
}
else if ("y".equalsIgnoreCase(unit)) {
y(n);
}
}
private long upperCeiling(long x) {
return (x / 100) * (100 - CEILING_PERCENTAGE);
}
private long lowerCeiling(long x) {
return (x / 100) * CEILING_PERCENTAGE;
}
private String ceil(long d, long n) {
return Integer.toString((int) Math.ceil((double) d / n));
}
private String floor(long d, long n) {
return Integer.toString((int) Math.floor((double) d / n));
}
/**
* Adds one year to the time delta.
*
* @return this HumanTime object
*/
public HumanTime y() {
return y(1);
}
/**
* Adds n years to the time delta.
*
* @param n n
* @return this HumanTime object
*/
public HumanTime y(int n) {
delta += YEAR * Math.abs(n);
return this;
}
/**
* Adds one day to the time delta.
*
* @return this HumanTime object
*/
public HumanTime d() {
return d(1);
}
/**
* Adds n days to the time delta.
*
* @param n n
* @return this HumanTime object
*/
public HumanTime d(int n) {
delta += DAY * Math.abs(n);
return this;
}
/**
* Adds one hour to the time delta.
*
* @return this HumanTime object
*/
public HumanTime h() {
return h(1);
}
/**
* Adds n hours to the time delta.
*
* @param n n
* @return this HumanTime object
*/
public HumanTime h(int n) {
delta += HOUR * Math.abs(n);
return this;
}
/**
* Adds one month to the time delta.
*
* @return this HumanTime object
*/
public HumanTime m() {
return m(1);
}
/**
* Adds n months to the time delta.
*
* @param n n
* @return this HumanTime object
*/
public HumanTime m(int n) {
delta += MINUTE * Math.abs(n);
return this;
}
/**
* Adds one second to the time delta.
*
* @return this HumanTime object
*/
public HumanTime s() {
return s(1);
}
/**
* Adds n seconds to the time delta.
*
* @param n seconds
* @return this HumanTime object
*/
public HumanTime s(int n) {
delta += SECOND * Math.abs(n);
return this;
}
/**
* Adds one millisecond to the time delta.
*
* @return this HumanTime object
*/
public HumanTime ms() {
return ms(1);
}
/**
* Adds n milliseconds to the time delta.
*
* @param n n
* @return this HumanTime object
*/
public HumanTime ms(int n) {
delta += Math.abs(n);
return this;
}
/**
* Returns a human-formatted representation of the time delta.
*
* @return a formatted representation of the time delta, never <code>null</code>
*/
public String getExactly() {
return getExactly(new StringBuilder()).toString();
}
/**
* Appends a human-formatted representation of the time delta to the given {@link Appendable} object.
*
* @param <T> the return type
* @param a the Appendable object, may not be <code>null</code>
* @return the given Appendable object, never <code>null</code>
*/
public <T extends Appendable> T getExactly(T a) {
try {
boolean prependBlank = false;
long d = delta;
if (d >= YEAR) {
a.append(floor(d, YEAR));
a.append(' ');
a.append('y');
prependBlank = true;
}
d %= YEAR;
if (d >= DAY) {
if (prependBlank) {
a.append(' ');
}
a.append(floor(d, DAY));
a.append(' ');
a.append('d');
prependBlank = true;
}
d %= DAY;
if (d >= HOUR) {
if (prependBlank) {
a.append(' ');
}
a.append(floor(d, HOUR));
a.append(' ');
a.append('h');
prependBlank = true;
}
d %= HOUR;
if (d >= MINUTE) {
if (prependBlank) {
a.append(' ');
}
a.append(floor(d, MINUTE));
a.append(' ');
a.append('m');
prependBlank = true;
}
d %= MINUTE;
if (d >= SECOND) {
if (prependBlank) {
a.append(' ');
}
a.append(floor(d, SECOND));
a.append(' ');
a.append('s');
prependBlank = true;
}
d %= SECOND;
if (d > 0) {
if (prependBlank) {
a.append(' ');
}
a.append(Integer.toString((int) d));
a.append(' ');
a.append('m');
a.append('s');
}
}
catch (IOException ex) {
// What were they thinking...
}
return a;
}
/**
* Returns an approximate, human-formatted representation of the time delta.
*
* @return a formatted representation of the time delta, never <code>null</code>
*/
public String getApproximately() {
return getApproximately(new StringBuilder()).toString();
}
/**
* Appends an approximate, human-formatted representation of the time delta to the given {@link Appendable} object.
*
* @param <T> the return type
* @param a the Appendable object, may not be <code>null</code>
* @return the given Appendable object, never <code>null</code>
*/
public <T extends Appendable> T getApproximately(T a) {
try {
int parts = 0;
boolean rounded = false;
boolean prependBlank = false;
long d = delta;
long mod = d % YEAR;
if (mod >= upperCeiling(YEAR)) {
a.append(ceil(d, YEAR));
a.append(' ');
a.append('y');
++parts;
rounded = true;
prependBlank = true;
}
else if (d >= YEAR) {
a.append(floor(d, YEAR));
a.append(' ');
a.append('y');
++parts;
rounded = mod <= lowerCeiling(YEAR);
prependBlank = true;
}
if (!rounded) {
d %= YEAR;
mod = d % DAY;
if (mod >= upperCeiling(DAY)) {
if (prependBlank) {
a.append(' ');
}
a.append(ceil(d, DAY));
a.append(' ');
a.append('d');
++parts;
rounded = true;
prependBlank = true;
}
else if (d >= DAY) {
if (prependBlank) {
a.append(' ');
}
a.append(floor(d, DAY));
a.append(' ');
a.append('d');
++parts;
rounded = mod <= lowerCeiling(DAY);
prependBlank = true;
}
if (parts < 2) {
d %= DAY;
mod = d % HOUR;
if (mod >= upperCeiling(HOUR)) {
if (prependBlank) {
a.append(' ');
}
a.append(ceil(d, HOUR));
a.append(' ');
a.append('h');
++parts;
rounded = true;
prependBlank = true;
}
else if (d >= HOUR && !rounded) {
if (prependBlank) {
a.append(' ');
}
a.append(floor(d, HOUR));
a.append(' ');
a.append('h');
++parts;
rounded = mod <= lowerCeiling(HOUR);
prependBlank = true;
}
if (parts < 2) {
d %= HOUR;
mod = d % MINUTE;
if (mod >= upperCeiling(MINUTE)) {
if (prependBlank) {
a.append(' ');
}
a.append(ceil(d, MINUTE));
a.append(' ');
a.append('m');
++parts;
rounded = true;
prependBlank = true;
}
else if (d >= MINUTE && !rounded) {
if (prependBlank) {
a.append(' ');
}
a.append(floor(d, MINUTE));
a.append(' ');
a.append('m');
++parts;
rounded = mod <= lowerCeiling(MINUTE);
prependBlank = true;
}
if (parts < 2) {
d %= MINUTE;
mod = d % SECOND;
if (mod >= upperCeiling(SECOND)) {
if (prependBlank) {
a.append(' ');
}
a.append(ceil(d, SECOND));
a.append(' ');
a.append('s');
++parts;
rounded = true;
prependBlank = true;
}
else if (d >= SECOND && !rounded) {
if (prependBlank) {
a.append(' ');
}
a.append(floor(d, SECOND));
a.append(' ');
a.append('s');
++parts;
rounded = mod <= lowerCeiling(SECOND);
prependBlank = true;
}
if (parts < 2) {
d %= SECOND;
if (d > 0 && !rounded) {
if (prependBlank) {
a.append(' ');
}
a.append(Integer.toString((int) d));
a.append(' ');
a.append('m');
a.append('s');
}
}
}
}
}
}
}
catch (IOException ex) {
// What were they thinking...
}
return a;
}
/**
* Returns the time delta.
*
* @return the time delta
*/
public long getDelta() {
return delta;
}
/**
* @see java.lang.Object#equals(java.lang.Object)
*/
@Override
public boolean equals(Object obj) {
if (this == obj) {
return true;
}
if (!(obj instanceof HumanTime)) {
return false;
}
return delta == ((HumanTime) obj).delta;
}
/**
* Returns a 32-bit representation of the time delta.
*
* @see java.lang.Object#hashCode()
*/
@Override
public int hashCode() {
return (int) (delta ^ (delta >> 32));
}
/**
* Returns a String representation of this.
* <p>
* The output is identical to {@link #getExactly()}.
*
* @see java.lang.Object#toString()
* @see #getExactly()
* @return a String, never <code>null</code>
*/
@Override
public String toString() {
return getExactly();
}
/**
* Compares this HumanTime to another HumanTime.
*
* @param t the other instance, may not be <code>null</code>
* @return which one is greater
*/
public int compareTo(HumanTime t) {
return delta == t.delta ? 0 : (delta < t.delta ? -1 : 1);
}
/**
* Deep-clones this object.
*
* @see java.lang.Object#clone()
* @throws CloneNotSupportedException
*/
@Override
public Object clone() throws CloneNotSupportedException {
return super.clone();
}
/**
* @see java.io.Externalizable#readExternal(java.io.ObjectInput)
*/
public void readExternal(ObjectInput in) throws IOException {
delta = in.readLong();
}
/**
* @see java.io.Externalizable#writeExternal(java.io.ObjectOutput)
*/
public void writeExternal(ObjectOutput out) throws IOException {
out.writeLong(delta);
}
}