com.cronutils.model.time.generator.OnDayOfMonthValueGenerator.java Source code

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Here is the source code for com.cronutils.model.time.generator.OnDayOfMonthValueGenerator.java

Source

package com.cronutils.model.time.generator;

import com.cronutils.model.field.CronField;
import com.cronutils.model.field.CronFieldName;
import com.cronutils.model.field.expression.FieldExpression;
import com.cronutils.model.field.expression.On;
import com.google.common.collect.Lists;
import org.apache.commons.lang3.Validate;
import org.joda.time.DateTime;

import java.util.List;

/*
 * Copyright 2015 jmrozanec
 * 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.
 */
class OnDayOfMonthValueGenerator extends FieldValueGenerator {
    private int year;
    private int month;

    public OnDayOfMonthValueGenerator(CronField cronField, int year, int month) {
        super(cronField.getExpression());
        Validate.isTrue(CronFieldName.DAY_OF_MONTH.equals(cronField.getField()),
                "CronField does not belong to day of month");
        this.year = year;
        this.month = month;
    }

    @Override
    public int generateNextValue(int reference) throws NoSuchValueException {
        On on = ((On) expression);
        int value = generateValue(on, year, month);

        if (value <= reference) {
            throw new NoSuchValueException();
        }
        return value;
    }

    @Override
    public int generatePreviousValue(int reference) throws NoSuchValueException {
        On on = ((On) expression);
        int value = generateValue(on, year, month);
        if (value >= reference) {
            throw new NoSuchValueException();
        }
        return value;
    }

    @Override
    protected List<Integer> generateCandidatesNotIncludingIntervalExtremes(int start, int end) {
        List<Integer> values = Lists.newArrayList();
        try {
            int reference = generateNextValue(start);
            while (reference < end) {
                values.add(reference);
                reference = generateNextValue(reference);
            }
        } catch (NoSuchValueException e) {
        }
        return values;
    }

    @Override
    public boolean isMatch(int value) {
        On on = ((On) expression);
        try {
            return value == generateValue(on, year, month);
        } catch (NoSuchValueException e) {
        }
        return false;
    }

    @Override
    protected boolean matchesFieldExpressionClass(FieldExpression fieldExpression) {
        return fieldExpression instanceof On;
    }

    private int generateValue(On on, int year, int month) throws NoSuchValueException {
        int time = on.getTime().getValue();
        switch (on.getSpecialChar().getValue()) {
        case L:
            return new DateTime(year, month, 1, 1, 1).dayOfMonth().getMaximumValue();
        case W:
            DateTime doM = new DateTime(year, month, time, 1, 1);
            if (doM.getDayOfWeek() == 6) {//dayOfWeek is Saturday!
                if (time == 1) {//first day in month is Saturday! We execute on Monday
                    return 3;
                }
                return time - 1;
            }
            if (doM.getDayOfWeek() == 7) {
                if ((time + 1) <= doM.dayOfMonth().getMaximumValue()) {
                    return time + 1;
                }
            }
            break;
        case LW:
            DateTime lastDayOfMonth = new DateTime(year, month,
                    new DateTime(year, month, 1, 1, 1).dayOfMonth().getMaximumValue(), 1, 1);
            int dow = lastDayOfMonth.getDayOfWeek();
            int diff = dow - 5;
            if (diff > 0) {
                return lastDayOfMonth.minusDays(diff).dayOfMonth().get();
            }
            return lastDayOfMonth.dayOfMonth().get();
        }
        throw new NoSuchValueException();
    }
}