fc.cron.CronExpression Maven / Gradle / Ivy
/*
* Copyright (C) 2012 Frode Carlsen.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package fc.cron;
/*-
* #%L
* frode-carlsen/cron
* %%
* Copyright (C) 2014 - 2017 frode-carlsen
* %%
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
* #L%
*/
import static org.joda.time.DateTimeConstants.DAYS_PER_WEEK;
import org.joda.time.DateTime;
import org.joda.time.LocalDate;
import org.joda.time.MutableDateTime;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
import java.util.Locale;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
/**
* Parser for unix-like cron expressions: Cron expressions allow specifying combinations of criteria for time
* such as: "Each Monday-Friday at 08:00" or "Every last friday of the month at 01:30"
*
* A cron expressions consists of 5 or 6 mandatory fields (seconds may be omitted) separated by space.
* These are:
*
*
*
* Field
*
* Allowable values
*
* Special Characters
*
*
* Seconds (may be omitted)
* 0-59
* , - * /
*
* Minutes
* 0-59
* , - * /
*
* Hours
* 0-23
* , - * /
*
* Day of month
* 1-31
* , - * ? / L W
*
* Month
* 1-12 or JAN-DEC (note: english abbreviations)
* , - * /
*
* Day of week
* 1-7 or MON-SUN (note: english abbreviations)
* , - * ? / L #
*
*
*
* '*' Can be used in all fields and means 'for all values'. E.g. "*" in minutes, means 'for all minutes'
*
* '?' Ca be used in Day-of-month and Day-of-week fields. Used to signify 'no special value'. It is used when one want
* to specify something for one of those two fields, but not the other.
*
* '-' Used to specify a time interval. E.g. "10-12" in Hours field means 'for hours 10, 11 and 12'
*
* ',' Used to specify multiple values for a field. E.g. "MON,WED,FRI" in Day-of-week field means "for
* monday, wednesday and friday"
*
* '/' Used to specify increments. E.g. "0/15" in Seconds field means "for seconds 0, 15, 30, ad
* 45". And "5/15" in seconds field means "for seconds 5, 20, 35, and 50". If '*' s specified
* before '/' it is the same as saying it starts at 0. For every field there's a list of values that can be turned on or
* off. For Seconds and Minutes these range from 0-59. For Hours from 0 to 23, For Day-of-month it's 1 to 31, For Months
* 1 to 12. "/" character helsp turn some of these values back on. Thus "7/6" in Months field
* specify just Month 7. It doesn't turn on every 6 month following, since cron fields never roll over
*
* 'L' Can be used on Day-of-month and Day-of-week fields. It signifies last day of the set of allowed values. In
* Day-of-month field it's the last day of the month (e.g.. 31 jan, 28 feb (29 in leap years), 31 march, etc.). In
* Day-of-week field it's Sunday. If there's a prefix, this will be subtracted (5L in Day-of-month means 5 days before
* last day of Month: 26 jan, 23 feb, etc.)
*
* 'W' Can be specified in Day-of-Month field. It specifies closest weekday (monday-friday). Holidays are not accounted
* for. "15W" in Day-of-Month field means 'closest weekday to 15 i in given month'. If the 15th is a Saturday,
* it gives Friday. If 15th is a Sunday, the it gives following Monday.
*
* '#' Can be used in Day-of-Week field. For example: "5#3" means 'third friday in month' (day 5 = friday, #3
* - the third). If the day does not exist (e.g. "5#5" - 5th friday of month) and there aren't 5 fridays in
* the month, then it won't match until the next month with 5 fridays.
*
* Case-sensitivt No fields are case-sensitive
*
* Dependencies between fields Fields are always evaluated independently, but the expression doesn't match until
* the constraints of each field are met.Feltene evalueres Overlap of intervals are not allowed. That is: for
* Day-of-week field "FRI-MON" is invalid,but "FRI-SUN,MON" is valid
*
*/
public class CronExpression {
enum CronFieldType {
SECOND(0, 59, null),
MINUTE(0, 59, null),
HOUR(0, 23, null),
DAY_OF_MONTH(1, 31, null),
MONTH(1, 12, Arrays.asList("JAN", "FEB", "MAR", "APR", "MAY", "JUN", "JUL", "AUG", "SEP", "OCT", "NOV", "DEC")),
DAY_OF_WEEK(1, 7, Arrays.asList("MON", "TUE", "WED", "THU", "FRI", "SAT", "SUN"));
final int from, to;
final List names;
CronFieldType(int from, int to, List names) {
this.from = from;
this.to = to;
this.names = names;
}
}
private final String expr;
private final SimpleField secondField;
private final SimpleField minuteField;
private final SimpleField hourField;
private final DayOfWeekField dayOfWeekField;
private final SimpleField monthField;
private final DayOfMonthField dayOfMonthField;
public CronExpression(final String expr) {
this(expr, true);
}
public CronExpression(final String expr, final boolean withSeconds) {
if (expr == null) {
throw new IllegalArgumentException("expr is null"); //$NON-NLS-1$
}
this.expr = expr;
final int expectedParts = withSeconds ? 6 : 5;
final String[] parts = expr.split("\\s+"); //$NON-NLS-1$
if (parts.length != expectedParts) {
throw new IllegalArgumentException(String.format("Invalid cron expression [%s], expected %s felt, got %s"
, expr, expectedParts, parts.length));
}
int ix = withSeconds ? 1 : 0;
this.secondField = new SimpleField(CronFieldType.SECOND, withSeconds ? parts[0] : "0");
this.minuteField = new SimpleField(CronFieldType.MINUTE, parts[ix++]);
this.hourField = new SimpleField(CronFieldType.HOUR, parts[ix++]);
this.dayOfMonthField = new DayOfMonthField(parts[ix++]);
this.monthField = new SimpleField(CronFieldType.MONTH, parts[ix++]);
this.dayOfWeekField = new DayOfWeekField(parts[ix++]);
}
public static CronExpression create(final String expr) {
return new CronExpression(expr, true);
}
public static CronExpression createWithoutSeconds(final String expr) {
return new CronExpression(expr, false);
}
public DateTime nextTimeAfter(DateTime afterTime) {
// will search for the next time within the next 4 years. If there is no
// time matching, an InvalidArgumentException will be thrown (it is very
// likely that the cron expression is invalid, like the February 30th).
return nextTimeAfter(afterTime, afterTime.plusYears(4));
}
public DateTime nextTimeAfter(DateTime afterTime, long durationInMillis) {
// will search for the next time within the next durationInMillis
// millisecond. Be aware that the duration is specified in millis,
// but in fact the limit is checked on a day-to-day basis.
return nextTimeAfter(afterTime, afterTime.plus(durationInMillis));
}
public DateTime nextTimeAfter(DateTime afterTime, DateTime dateTimeBarrier) {
MutableDateTime nextTime = new MutableDateTime(afterTime);
nextTime.setMillisOfSecond(0);
nextTime.secondOfDay().add(1);
while (true) { // day of week
while (true) { // month
while (true) { // day of month
while (true) { // hour
while (true) { // minute
while (true) { // second
if (secondField.matches(nextTime.getSecondOfMinute())) {
break;
}
nextTime.secondOfDay().add(1);
}
if (minuteField.matches(nextTime.getMinuteOfHour())) {
break;
}
nextTime.minuteOfDay().add(1);
nextTime.secondOfMinute().set(0);
}
if (hourField.matches(nextTime.getHourOfDay())) {
break;
}
nextTime.hourOfDay().add(1);
nextTime.minuteOfHour().set(0);
nextTime.secondOfMinute().set(0);
}
if (dayOfMonthField.matches(new LocalDate(nextTime))) {
break;
}
nextTime.addDays(1);
nextTime.setTime(0, 0, 0, 0);
checkIfDateTimeBarrierIsReached(nextTime, dateTimeBarrier);
}
if (monthField.matches(nextTime.getMonthOfYear())) {
break;
}
nextTime.addMonths(1);
nextTime.setDayOfMonth(1);
nextTime.setTime(0, 0, 0, 0);
checkIfDateTimeBarrierIsReached(nextTime, dateTimeBarrier);
}
if (dayOfWeekField.matches(new LocalDate(nextTime))) {
break;
}
nextTime.addDays(1);
nextTime.setTime(0, 0, 0, 0);
checkIfDateTimeBarrierIsReached(nextTime, dateTimeBarrier);
}
return nextTime.toDateTime();
}
private static void checkIfDateTimeBarrierIsReached(MutableDateTime nextTime, DateTime dateTimeBarrier) {
if (nextTime.isAfter(dateTimeBarrier)) {
throw new IllegalArgumentException("No next execution time could be determined that is before the limit of " + dateTimeBarrier);
}
}
@Override
public String toString() {
return getClass().getSimpleName() + "<" + expr + ">";
}
static class FieldPart {
private Integer from, to, increment;
private String modifier, incrementModifier;
}
abstract static class BasicField {
private static final Pattern CRON_FELT_REGEXP = Pattern
.compile("(?: # start of group 1\n"
+ " (?:(?\\*)|(?\\?)|(?L)) # globalt flag (L, ?, *)\n"
+ " | (?[0-9]{1,2}|[a-z]{3,3}) # or start number or symbol\n"
+ " (?: # start of group 2\n"
+ " (?L|W) # modifier (L,W)\n"
+ " | -(?[0-9]{1,2}|[a-z]{3,3}) # or end nummer or symbol (in range)\n"
+ " )? # end of group 2\n"
+ ") # end of group 1\n"
+ "(?:(?/|\\#)(?[0-9]{1,7}))? # increment and increment modifier (/ or \\#)\n"
, Pattern.CASE_INSENSITIVE | Pattern.COMMENTS);
final CronFieldType fieldType;
final List parts = new ArrayList();
private BasicField(CronFieldType fieldType, String fieldExpr) {
this.fieldType = fieldType;
parse(fieldExpr);
}
private void parse(String fieldExpr) { // NOSONAR
String[] rangeParts = fieldExpr.split(",");
for (String rangePart : rangeParts) {
Matcher m = CRON_FELT_REGEXP.matcher(rangePart);
if (!m.matches()) {
throw new IllegalArgumentException("Invalid cron field '" + rangePart + "' for field [" + fieldType + "]");
}
String startNummer = m.group("start");
String modifier = m.group("mod");
String sluttNummer = m.group("end");
String inkrementModifier = m.group("inkmod");
String inkrement = m.group("ink");
FieldPart part = new FieldPart();
part.increment = 999;
if (startNummer != null) {
part.from = mapValue(startNummer);
part.modifier = modifier;
if (sluttNummer != null) {
part.to = mapValue(sluttNummer);
part.increment = 1;
} else if (inkrement != null) {
part.to = fieldType.to;
} else {
part.to = part.from;
}
} else if (m.group("all") != null) {
part.from = fieldType.from;
part.to = fieldType.to;
part.increment = 1;
} else if (m.group("ignorer") != null) {
part.modifier = m.group("ignorer");
} else if (m.group("last") != null) {
part.modifier = m.group("last");
} else {
throw new IllegalArgumentException("Invalid cron part: " + rangePart);
}
if (inkrement != null) {
part.incrementModifier = inkrementModifier;
part.increment = Integer.valueOf(inkrement);
}
validateRange(part);
validatePart(part);
parts.add(part);
}
}
protected void validatePart(FieldPart part) {
if (part.modifier != null) {
throw new IllegalArgumentException(String.format("Invalid modifier [%s]", part.modifier));
} else if (part.incrementModifier != null && !"/".equals(part.incrementModifier)) {
throw new IllegalArgumentException(String.format("Invalid increment modifier [%s]", part.incrementModifier));
}
}
private void validateRange(FieldPart part) {
if ((part.from != null && part.from < fieldType.from) || (part.to != null && part.to > fieldType.to)) {
throw new IllegalArgumentException(String.format("Invalid interval [%s-%s], must be %s<=_<=%s", part.from, part.to, fieldType.from,
fieldType.to));
} else if (part.from != null && part.to != null && part.from > part.to) {
throw new IllegalArgumentException(
String.format(
"Invalid interval [%s-%s]. Rolling periods are not supported (ex. 5-1, only 1-5) since this won't give a deterministic result. Must be %s<=_<=%s",
part.from, part.to, fieldType.from, fieldType.to));
}
}
protected Integer mapValue(String value) {
Integer idx;
if (fieldType.names != null && (idx = fieldType.names.indexOf(value.toUpperCase(Locale.getDefault()))) >= 0) {
return idx + 1;
}
return Integer.valueOf(value);
}
protected boolean matches(int val, FieldPart part) {
if (val >= part.from && val <= part.to && (val - part.from) % part.increment == 0) {
return true;
}
return false;
}
}
static class SimpleField extends BasicField {
SimpleField(CronFieldType fieldType, String fieldExpr) {
super(fieldType, fieldExpr);
}
public boolean matches(int val) {
if (val >= fieldType.from && val <= fieldType.to) {
for (FieldPart part : parts) {
if (matches(val, part)) {
return true;
}
}
}
return false;
}
}
static class DayOfWeekField extends BasicField {
DayOfWeekField(String fieldExpr) {
super(CronFieldType.DAY_OF_WEEK, fieldExpr);
}
boolean matches(LocalDate dato) {
for (FieldPart part : parts) {
if ("L".equals(part.modifier)) {
return dato.getDayOfWeek() == part.from && dato.getDayOfMonth() > (dato.dayOfMonth().getMaximumValue() - DAYS_PER_WEEK);
} else if ("#".equals(part.incrementModifier)) {
if (dato.getDayOfWeek() == part.from) {
int num = dato.getDayOfMonth() / 7;
return part.increment == (dato.getDayOfMonth() % 7 == 0 ? num : num + 1);
}
return false;
} else if (matches(dato.getDayOfWeek(), part)) {
return true;
}
}
return false;
}
@Override
protected Integer mapValue(String value) {
// Use 1-7 for weedays, but 0 will also represent sunday (linux practice)
return "0".equals(value) ? Integer.valueOf(7) : super.mapValue(value);
}
@Override
protected boolean matches(int val, FieldPart part) {
return "?".equals(part.modifier) || super.matches(val, part);
}
@Override
protected void validatePart(FieldPart part) {
if (part.modifier != null && Arrays.asList("L", "?").indexOf(part.modifier) == -1) {
throw new IllegalArgumentException(String.format("Invalid modifier [%s]", part.modifier));
} else if (part.incrementModifier != null && Arrays.asList("/", "#").indexOf(part.incrementModifier) == -1) {
throw new IllegalArgumentException(String.format("Invalid increment modifier [%s]", part.incrementModifier));
}
}
}
static class DayOfMonthField extends BasicField {
DayOfMonthField(String fieldExpr) {
super(CronFieldType.DAY_OF_MONTH, fieldExpr);
}
boolean matches(LocalDate dato) {
for (FieldPart part : parts) {
if ("L".equals(part.modifier)) {
return dato.getDayOfMonth() == (dato.dayOfMonth().getMaximumValue() - (part.from == null ? 0 : part.from));
} else if ("W".equals(part.modifier)) {
if (dato.getDayOfWeek() <= 5) {
if (dato.getDayOfMonth() == part.from) {
return true;
} else if (dato.getDayOfWeek() == 5) {
return dato.plusDays(1).getDayOfMonth() == part.from;
} else if (dato.getDayOfWeek() == 1) {
return dato.minusDays(1).getDayOfMonth() == part.from;
}
}
} else if (matches(dato.getDayOfMonth(), part)) {
return true;
}
}
return false;
}
@Override
protected void validatePart(FieldPart part) {
if (part.modifier != null && Arrays.asList("L", "W", "?").indexOf(part.modifier) == -1) {
throw new IllegalArgumentException(String.format("Invalid modifier [%s]", part.modifier));
} else if (part.incrementModifier != null && !"/".equals(part.incrementModifier)) {
throw new IllegalArgumentException(String.format("Invalid increment modifier [%s]", part.incrementModifier));
}
}
@Override
protected boolean matches(int val, FieldPart part) {
return "?".equals(part.modifier) || super.matches(val, part);
}
}
}