@Override
public String toString() {
// 返回形如: 30s/5m@2m30s，读作: 以30秒切割5分钟周期，当前偏移量为第2分钟30秒
return TimeInterval.parse(interval)
+ "/"
+ TimeInterval.parse(total)
+ "@"
+ TimeInterval.parse(currentOffset);
}
@Override
public BoundaryCronTrigger create(TimeInterval frequency, Schedule schedule, TimeSpan window) {
if (frequency.getMilliseconds() % 15 * DateUtils.MILLIS_PER_SECOND != 0) {
throw new IllegalArgumentException(
"The frequency " + frequency + " can't be divided by system minimal interval(15s)");
}
int pos, val;
String interval = frequency.getInterval();
if (interval.contains("h")) {
pos = 2;
val = Integer.valueOf(interval.substring(0, interval.indexOf('h')));
} else if (interval.contains("m")) {
pos = 1;
val = Integer.valueOf(interval.substring(0, interval.indexOf('m')));
} else if (interval.contains("s")) {
pos = 0;
val = Integer.valueOf(interval.substring(0, interval.indexOf('s')));
} else {
throw new IllegalArgumentException(
"The interval " + interval + " is invalid, we only support h/m/s");
}
// 如果连系统都没有设置默认的监控的频度，那么我们默认设置为所有时间
String[] cron =
schedule == null
? new String[] {"*", "*", "*", "*", "*", "*"}
: schedule.getCron().split("\\s");
Granularity granularity = getGranularity(frequency);
// 不同的频度，还需要削峰填谷
// 在频度之前的每个字段，先归置为0
for (int i = 0; i < pos; i++) {
cron[i] = granularity.getSegment(i);
}
// 在小时这里，schedule和frequency的偏移量可能出现冲突
// 原则是，保留 schedule的限制
cron[pos] = granularity.getSegment(pos) + "/" + val;
// 向上计数，下个该间隔的计划自然向上偏移
granularity.stepUp();
String expression = StringUtils.join(cron, " ");
BoundaryCronTrigger trigger = new BoundaryCronTrigger(expression);
trigger.include(schedule);
trigger.exclude(window);
return trigger;
}
/**
*
*
* <h2>返回当前偏移量在特定cron位置上面的表达</h2>
*
* @param i cron位置
* @return 偏移量表达
*/
public String getSegment(int i) {
// 0(second): 1 (s)
// 1(minute): 60 (s)
// 2(hour) : 36,00 (s)
if (i > 2) throw new UnsupportedOperationException("Can't support offset greater than hour");
// 1h1m30s
String offset = TimeInterval.parse(currentOffset);
Pattern pattern = patterns[i];
Matcher matcher = pattern.matcher(offset);
if (matcher.find()) {
return matcher.group(1);
} else {
return "0";
}
}
void setGranularity(TimeInterval frequency, int granularity) {
int interval = (int) (frequency.getMilliseconds() / granularity);
Granularity g = new Granularity((int) frequency.getMilliseconds(), interval);
granularities.put(frequency, g);
}