JBPM4.4代码org.jbpm.pvm.internal.cal.Duration
/*
* JBoss, Home of Professional Open Source
* Copyright 2005, JBoss Inc., and individual contributors as indicated
* by the @authors tag. See the copyright.txt in the distribution for a
* full listing of individual contributors.
*
* This 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 software 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 software; if not, write to the Free
* Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
* 02110-1301 USA, or see the FSF site: http://www.fsf.org.
*/
package org.jbpm.pvm.internal.cal;
import java.io.Serializable;
import java.util.ArrayList;
import java.util.Calendar;
import java.util.Date;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.regex.Pattern;
import org.jbpm.api.Execution;
import org.jbpm.api.JbpmException;
import org.jbpm.pvm.internal.el.Expression;
import org.jbpm.pvm.internal.env.EnvironmentImpl;
import org.jbpm.pvm.internal.util.Clock;
/**
* represents a time duration.
*
* <p>With the constructor {link {@link #Duration(String)} you can create a
* Duration from a text representation. The syntax is as follows
* </p>
*
* <pre>
* duration = part [',' part | 'and' part]*
* part = number ['business'] unit
* number = (0..9)+
* unit = (y|year|years|month|months|w|week|weeks|d|day|days|h|hour|hours|min|minute|minutes|s|sec|second|seconds|milli|millis|millisecond|milliseconds)
* </pre>
*
* <p>Duration is immutable.
* </p>
*
* @author Huisheng Xu
*/
public class Duration implements Serializable {
private static final long serialVersionUID = 1L;
boolean isBusinessTime;
protected int millis;
protected int seconds;
protected int minutes;
protected int hours;
protected int days;
protected int weeks;
protected int months;
protected int years;
private final static String dateFormat = "yyyy-MM-dd HH:mm:ss";
private static final Pattern dateDurationPattern = Pattern.compile("\\s*(#\\{.+\\})\\s*"
+ "(?:(\\+|-)\\s*(\\d+\\s+(?:business\\s+)?\\w+))?\\s*");
private static final Pattern durationPattern = Pattern.compile("\\s*(\\d+\\s+(?:business\\s+)?"
+ "\\w+)\\s*");
/** constructor for persistence. note that this type is to be immutable. */
protected Duration() {
}
/** parses the duration from a text
*
* duration = part [',' part | 'and' part]*
* part = number ['business'] unit
* number = (0..9)+
* unit = (y|year|years|month|months|w|week|weeks|d|day|days|h|hour|hours|min|minute|minutes|s|sec|second|seconds|milli|millis|millisecond|milliseconds)
*
* @throws JbpmException if the parsing is unsuccessful
*/
public Duration(String text) {
if (text==null) throw new JbpmException("text is null");
for (String part: splitInParts(text)) {
parsePart(part);
}
isBusinessTime = text.indexOf("business")!=-1;
}
public static boolean isValidExpression(String durationExpression) {
try {
new Duration(durationExpression);
} catch (JbpmException e) {
return false;
}
return true;
}
public static Date calculateDueDate(String durationExpression) {
Date duedate = null;
if (durationExpression != null) {
Date baseDate;
String durationString = null;
char durationSeparator = '+'; // needs to be initialized
if (durationExpression.startsWith("#")) {
String baseDateEL = durationExpression.substring(0, durationExpression.indexOf("}") + 1);
Object result = Expression.create(baseDateEL).evaluate();
if (result instanceof Date) {
baseDate = (Date) result;
} else if (result instanceof Calendar) {
baseDate = ((Calendar) result).getTime();
} else if (result instanceof String) {
baseDate = Clock.getTime();
int endOfELIndex = durationExpression.indexOf("}");
if (endOfELIndex < (durationExpression.length() - 1)) {
throw new JbpmException("Invalid duedate, didnot support + or - in String type EL.");
}
durationString = (String) Expression.create(durationExpression, null).evaluate((Execution) null);
} else {
throw new JbpmException("Invalid basedate type: " + baseDateEL + " is of type "
+ result.getClass().getName()
+ ". Only Date and Calendar are supported");
}
if (durationString == null) {
int endOfELIndex = durationExpression.indexOf("}");
if (endOfELIndex < (durationExpression.length() - 1)) {
durationSeparator = durationExpression.substring(endOfELIndex + 1).trim().charAt(0);
if (durationSeparator != '+' && durationSeparator != '-') {
throw new JbpmException("Invalid duedate, + or - missing after EL");
}
durationString = durationExpression.substring(endOfELIndex + 1).substring(2).trim();
}
}
} else {
baseDate = Clock.getTime();
durationString = durationExpression;
}
if (durationString == null || durationString.length() == 0) {
duedate = baseDate;
} else {
if (durationString.contains("business") && durationSeparator == '-') {
throw new JbpmException("Invalid duedate, subtraction ('-') not supported if duedate contains 'business'");
}
BusinessCalendar businessCalendar = EnvironmentImpl.getFromCurrent(BusinessCalendar.class);
if (durationSeparator == '+') {
duedate = businessCalendar.add(baseDate, durationString);
} else {
duedate = businessCalendar.subtract(baseDate, durationString);
}
}
}
return duedate;
}
public Duration(boolean isBusinessTime, int millis, int seconds, int minutes, int hours, int days, int weeks, int months, int years) {
this.isBusinessTime = isBusinessTime;
this.millis = millis;
this.seconds = seconds;
this.minutes = minutes;
this.hours = hours;
this.days = days;
this.weeks = weeks;
this.months = months;
this.years = years;
}
private List<String> splitInParts(String text) {
List<String> parts = new ArrayList<String>(2);
while (text!=null) {
int commaIndex = text.indexOf(',');
int andIndex = text.indexOf(" and ");
if ( ( (commaIndex==-1)
&& (andIndex!=-1)
)
||
( ( (commaIndex!=-1)
&& (andIndex!=-1)
)
&& (andIndex<commaIndex)
)
) {
String part = text.substring(0, andIndex).trim();
parts.add(part);
text = text.substring(andIndex+5);
} else if ( ( (commaIndex!=-1)
&& (andIndex==-1)
)
||
( ( (commaIndex!=-1)
&& (andIndex!=-1)
)
&& (andIndex>commaIndex)
)
) {
String part = text.substring(0, commaIndex).trim();
parts.add(part);
text = text.substring(commaIndex+1);
} else {
parts.add(text.trim());
text = null;
}
}
return parts;
}
private void parsePart(String part) {
int spaceIndex = part.indexOf(' ');
if (spaceIndex==-1) {
throw new JbpmException("couldn't parse duration part "+part);
}
String quantityText = part.substring(0, spaceIndex).trim();
spaceIndex = part.lastIndexOf(' ');
String unitText = part.substring(spaceIndex+1).trim().toLowerCase();
int quantity;
try {
quantity = Integer.parseInt(quantityText);
} catch (NumberFormatException e) {
throw new JbpmException("couldn't parse quantity "+quantityText+" in duration text", e);
}
FieldSetter fieldSetter = fieldSetters.get(unitText);
if (fieldSetter==null) {
throw new JbpmException("couldn't parse quantity "+quantityText);
}
fieldSetter.set(this, quantity);
}
interface FieldSetter {
void set(Duration duration, int quantity);
}
static class MillisSetter implements FieldSetter {
public void set(Duration duration, int quantity) {
duration.millis = quantity;
}
}
static class SecondSetter implements FieldSetter {
public void set(Duration duration, int quantity) {
duration.seconds = quantity;
}
}
static class MinuteSetter implements FieldSetter {
public void set(Duration duration, int quantity) {
duration.minutes = quantity;
}
}
static class HourSetter implements FieldSetter {
public void set(Duration duration, int quantity) {
duration.hours = quantity;
}
}
static class DaySetter implements FieldSetter {
public void set(Duration duration, int quantity) {
duration.days = quantity;
}
}
static class WeekSetter implements FieldSetter {
public void set(Duration duration, int quantity) {
duration.weeks = quantity;
}
}
static class MonthSetter implements FieldSetter {
public void set(Duration duration, int quantity) {
duration.months = quantity;
}
}
static class YearSetter implements FieldSetter {
public void set(Duration duration, int quantity) {
duration.years = quantity;
}
}
private static final Map<String, FieldSetter> fieldSetters = new HashMap<String, FieldSetter>();
static {
FieldSetter fieldSetter = new MillisSetter();
fieldSetters.put("ms", fieldSetter);
fieldSetters.put("millis", fieldSetter);
fieldSetters.put("millisecond", fieldSetter);
fieldSetters.put("milliseconds", fieldSetter);
fieldSetter = new SecondSetter();
fieldSetters.put("s", fieldSetter);
fieldSetters.put("sec", fieldSetter);
fieldSetters.put("second", fieldSetter);
fieldSetters.put("seconds", fieldSetter);
fieldSetter = new MinuteSetter();
fieldSetters.put("min", fieldSetter);
fieldSetters.put("minute", fieldSetter);
fieldSetters.put("minutes", fieldSetter);
fieldSetter = new HourSetter();
fieldSetters.put("h", fieldSetter);
fieldSetters.put("hour", fieldSetter);
fieldSetters.put("hours", fieldSetter);
fieldSetter = new DaySetter();
fieldSetters.put("d", fieldSetter);
fieldSetters.put("day", fieldSetter);
fieldSetters.put("days", fieldSetter);
fieldSetter = new WeekSetter();
fieldSetters.put("w", fieldSetter);
fieldSetters.put("week", fieldSetter);
fieldSetters.put("weeks", fieldSetter);
fieldSetter = new MonthSetter();
fieldSetters.put("month", fieldSetter);
fieldSetters.put("months", fieldSetter);
fieldSetter = new YearSetter();
fieldSetters.put("y", fieldSetter);
fieldSetters.put("year", fieldSetter);
fieldSetters.put("years", fieldSetter);
}
public int getDays() {
return days;
}
public int getHours() {
return hours;
}
public boolean isBusinessTime() {
return isBusinessTime;
}
public int getMillis() {
return millis;
}
public int getMinutes() {
return minutes;
}
public int getMonths() {
return months;
}
public int getSeconds() {
return seconds;
}
public int getWeeks() {
return weeks;
}
public int getYears() {
return years;
}
}
这里有个策略模式的应用，duration构造函数中的参数可能带有year、month等，根据字符串的不同选择不同的算法，如果是我的实现可能就是if(str.equals("year"))..else if(str.equals("month"))...else if(str.equals("hour"))..
private void parsePart(String part) {
int spaceIndex = part.indexOf(' ');
if (spaceIndex==-1) {
throw new JbpmException("couldn't parse duration part "+part);
}
String quantityText = part.substring(0, spaceIndex).trim();
spaceIndex = part.lastIndexOf(' ');
String unitText = part.substring(spaceIndex+1).trim().toLowerCase();
int quantity;
try {
quantity = Integer.parseInt(quantityText);
} catch (NumberFormatException e) {
throw new JbpmException("couldn't parse quantity "+quantityText+" in duration text", e);
}
FieldSetter fieldSetter = fieldSetters.get(unitText);
if (fieldSetter==null) {
throw new JbpmException("couldn't parse quantity "+quantityText);
}
fieldSetter.set(this, quantity);
}
interface FieldSetter {
void set(Duration duration, int quantity);
}
static class MillisSetter implements FieldSetter {
public void set(Duration duration, int quantity) {
duration.millis = quantity;
}
}
static class SecondSetter implements FieldSetter {
public void set(Duration duration, int quantity) {
duration.seconds = quantity;
}
}
static class MinuteSetter implements FieldSetter {
public void set(Duration duration, int quantity) {
duration.minutes = quantity;
}
}
static class HourSetter implements FieldSetter {
public void set(Duration duration, int quantity) {
duration.hours = quantity;
}
}
static class DaySetter implements FieldSetter {
public void set(Duration duration, int quantity) {
duration.days = quantity;
}
}
static class WeekSetter implements FieldSetter {
public void set(Duration duration, int quantity) {
duration.weeks = quantity;
}
}
static class MonthSetter implements FieldSetter {
public void set(Duration duration, int quantity) {
duration.months = quantity;
}
}
static class YearSetter implements FieldSetter {
public void set(Duration duration, int quantity) {
duration.years = quantity;
}
}
private static final Map<String, FieldSetter> fieldSetters = new HashMap<String, FieldSetter>();
static {
FieldSetter fieldSetter = new MillisSetter();
fieldSetters.put("ms", fieldSetter);
fieldSetters.put("millis", fieldSetter);
fieldSetters.put("millisecond", fieldSetter);
fieldSetters.put("milliseconds", fieldSetter);
fieldSetter = new SecondSetter();
fieldSetters.put("s", fieldSetter);
fieldSetters.put("sec", fieldSetter);
fieldSetters.put("second", fieldSetter);
fieldSetters.put("seconds", fieldSetter);
fieldSetter = new MinuteSetter();
fieldSetters.put("min", fieldSetter);
fieldSetters.put("minute", fieldSetter);
fieldSetters.put("minutes", fieldSetter);
fieldSetter = new HourSetter();
fieldSetters.put("h", fieldSetter);
fieldSetters.put("hour", fieldSetter);
fieldSetters.put("hours", fieldSetter);
fieldSetter = new DaySetter();
fieldSetters.put("d", fieldSetter);
fieldSetters.put("day", fieldSetter);
fieldSetters.put("days", fieldSetter);
fieldSetter = new WeekSetter();
fieldSetters.put("w", fieldSetter);
fieldSetters.put("week", fieldSetter);
fieldSetters.put("weeks", fieldSetter);
fieldSetter = new MonthSetter();
fieldSetters.put("month", fieldSetter);
fieldSetters.put("months", fieldSetter);
fieldSetter = new YearSetter();
fieldSetters.put("y", fieldSetter);
fieldSetters.put("year", fieldSetter);
fieldSetters.put("years", fieldSetter);
}