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package com.yuweix.kuafu.sequence.bean;
import java.util.concurrent.atomic.AtomicLong;
import com.yuweix.kuafu.sequence.exception.SequenceException;
/**
* @author yuwei
*/
public class SequenceHolder {
private final long ceil;
private volatile AtomicLong currentValue;
public SequenceHolder(long min, long max) {
if (min <= 0) {
throw new SequenceException("[min] must be larger then 0.");
}
if (min >= max) {
throw new SequenceException("[max] must be larger then [min].");
}
this.currentValue = new AtomicLong(min);
this.ceil = max;
}
/**
* 获取一个值，如果超出范围，返回-1。
*/
public long getAndIncrement() {
long val = currentValue.getAndIncrement();
if (val > ceil) {
return -1L;
}
return val;
}
public long get() {
long val = currentValue.get();
if (val > ceil) {
return -1L;
}
return val;
}
}