com.pig4cloud.pigx.common.sequence.sequence.impl.DefaultRangeSequence Maven / Gradle / Ivy
package com.pig4cloud.pigx.common.sequence.sequence.impl;
import cn.hutool.core.date.DatePattern;
import cn.hutool.core.date.DateUtil;
import com.pig4cloud.pigx.common.sequence.exception.SeqException;
import com.pig4cloud.pigx.common.sequence.range.BizName;
import com.pig4cloud.pigx.common.sequence.range.SeqRange;
import com.pig4cloud.pigx.common.sequence.range.SeqRangeMgr;
import com.pig4cloud.pigx.common.sequence.sequence.RangeSequence;
import java.util.Date;
import java.util.Map;
import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.locks.Lock;
import java.util.concurrent.locks.ReentrantLock;
/**
* 序列号区间生成器接口默认实现
*
* @author xuan on 2018/1/10.
*
* 根据biz name 自增
*/
public class DefaultRangeSequence implements RangeSequence {
/**
* 获取区间是加一把独占锁防止资源冲突
*/
private final Lock lock = new ReentrantLock();
/**
* 序列号区间管理器
*/
private SeqRangeMgr seqRangeMgr;
/**
* 当前序列号区间
*/
private volatile SeqRange currentRange;
private static Map seqRangeMap = new ConcurrentHashMap<>(8);
/**
* 需要获取区间的业务名称
*/
private BizName bizName;
@Override
public long nextValue() throws SeqException {
String name = bizName.create();
currentRange = seqRangeMap.get(name);
// 当前区间不存在，重新获取一个区间
if (null == currentRange) {
lock.lock();
try {
if (null == currentRange) {
currentRange = seqRangeMgr.nextRange(name);
seqRangeMap.put(name, currentRange);
}
}
finally {
lock.unlock();
}
}
// 当value值为-1时，表明区间的序列号已经分配完，需要重新获取区间
long value = currentRange.getAndIncrement();
if (value == -1) {
lock.lock();
try {
for (;;) {
if (currentRange.isOver()) {
currentRange = seqRangeMgr.nextRange(name);
}
value = currentRange.getAndIncrement();
if (value == -1) {
continue;
}
break;
}
}
finally {
lock.unlock();
}
}
if (value < 0) {
throw new SeqException("Sequence value overflow, value = " + value);
}
return value;
}
/**
* 下一个生成序号（带格式）
* @return
* @throws SeqException
*/
@Override
public String nextNo() throws SeqException {
return String.format("%s%05d", DateUtil.format(new Date(), DatePattern.PURE_DATE_FORMAT), nextValue());
}
@Override
public void setSeqRangeMgr(SeqRangeMgr seqRangeMgr) {
this.seqRangeMgr = seqRangeMgr;
}
@Override
public void setName(BizName name) {
this.bizName = name;
}
}