下面这个类是获取数据库中一个字段的最大值。配置在数据库中。
public class NoFactory {
private final static Logger cLogger = Logger.getLogger(NoFactory.class);
protected static final byte cClusterId = 0;
protected static final byte cClusterCount = 1;
private static final byte[] BLCTRANNOId = new byte[0];
private static int BLCTRANNO;
static {
try {
BLCTRANNO = Integer.parseInt(new ExeSQL().getOneValue("select max(to_number(BLCTRANNO)) from edorrenewalbalanceacc where mod(BLCTRANNO,"+cClusterCount+")="+cClusterId));
} catch (Throwable ex) {
cLogger.error("初始化最大号异常！", ex);
}
}
public final static int nextBLCTRANNONo() {
synchronized (BLCTRANNOId) {
BLCTRANNO += cClusterCount;
}
return BLCTRANNO;
}
public final static void setBLCTRANNONo(int pMaxNo) {
synchronized (BLCTRANNOId) {
BLCTRANNO = pMaxNo - pMaxNo%cClusterCount + cClusterId;
}
}
}
数据库表中MAX ID获取,确保每次调用没有重复工具类（NumberUtil）的相关教程结束。
