Java Red Envelope rules

Java Red Envelope rules

Lucky Red Envelopes:

Rule: Maximum amount: Total amount/number * multiple

Minimum Amount: 0.01

The last red envelope is the full amount-the claim amount

Random allocation

 Packagecom.utils;ImportJava.math.BigDecimal;ImportJava.math.RoundingMode;Importjava.util.ArrayList;Importjava.util.List;ImportJava.util.Random;/*** Red Envelopes Distribution Tool class * */ Public classCashredpackutils {/*** A red envelope at least the number of split*/     Public Static Final intredpack_min_quantity = 1; /*** A red envelope maximum number of splits*/     Public Static Final intredpack_max_quantity = 100; /*** Decimal bit length*/    Private Static Final intScale = 2; /*** Discarded decimal digit processing mode*/    Private Static FinalRoundingmode Rounding_mode =Roundingmode.half_even; /*** Red envelope magnification*/    Private Static FinalBigDecimal times =NewBigDecimal ("3"); /*** Single red envelope Minimum Amount*/     Public Static FinalBigDecimal Single_red_min_money =NewBigDecimal ("0.01"); /*** Maximum amount of a single red envelope*///private static final BigDecimal Single_red_max_money = new BigDecimal ("+");    /*** Recursive calculation of red envelope amount when the maximum consecutive error, more than this number will return the minimum value*/    Private Static Final intError_max_num = 5; /*** Recursive calculation of red envelope amount consecutive error number initial value*/    Private Static Final intError_init_num = 1; /*** Decimal place when calculating the amount, 1000 for 3 decimal places*/    Private Static Final intFraction_length = 1000; /*** Distribute Red envelopes *@paramRedmoney Red Envelope Total amount *@paramnum Bonus Number *@return     */     Public StaticList<bigdecimal> Splitredpackes (BigDecimal Redmoney,intnum) {

list<bigdecimal> redinfolist = new arraylist<>();
Red envelopes Wrong
if (num < redpack_min_quantity | | num > redpack_max_quantity)
　　　　　　return redinfolist;

//Checksum: Amount greater than 0        if(Redmoney.compareto (bigdecimal.zero)! = 1) {            returnredinfolist; }                if(Num <= 1) {redinfolist.add (Redmoney); returnredinfolist; } Random Random=NewRandom ();  for(inti = 0; i < num; i++) {//System.out.println ("\ n" + (I+1) + "Packet Information:");            intSurplusnum = Num-i;//amount of red envelopes not allocatedBigDecimal Curredmoney =fightluckredpacked (Redmoney, Surplusnum, Random, error_init_num);            Redinfolist.add (Curredmoney); Redmoney=redmoney.subtract (Curredmoney); Mandoassert.nottrue (Redmoney.compareto (Bigdecimal.zero)= =-1, "red envelope amount is wrong");//System.out.println ("Red Envelope amount:" + Curredmoney + ", Remaining:" + Redmoney);        }        returnredinfolist; }        /*** Lucky Red Envelopes *@paramRedmoney Red Envelope amount *@paramnum Bonus Number *@paramrandom Number Generation Object *@paramerrornum Error Test *@returnsingle Red envelope amount*/    Private StaticBigDecimal fightluckredpacked (BigDecimal Redmoney,intnum, Random random,interrornum) {        if(Num <= 1) {            returnRedmoney; }        if(ErrorNum >error_max_num) {            //The random amount generates an error more than the upper limit and returns the minimum value            returnSingle_red_min_money; }        //maximum amount per red envelope = amount of total remaining/unallocated amount * red envelope magnification        intAvgredmaxmoney = Redmoney.divide (NewBigDecimal (num), rounding_mode). Multiply (times). Intvalue () *fraction_length; BigDecimal Curredmoney=NewBigDecimal (Random.nextint (Avgredmaxmoney) * 1.00/fraction_length + ""). Setscale (scale, rounding_mode); if(Curredmoney.compareto (Single_red_min_money) = =-1) {            //Red Envelope minimum value: Less than the minimum bonus amount, recalculate            returnfightluckredpacked (Redmoney, num, random, + +)errornum); }        /*if (Curredmoney.compareto (single_red_max_money) = = 1) {//Red envelope maximum value is determined by return fightluckredpacked (Curre        Dmoney, num, random, ++errornum); }*/        //minimum reserved Bonus amountBigDecimal Surplusminredmoney = single_red_min_money.multiply (NewBigDecimal (num-1)); //In addition to the current amount remaining in red envelopesBigDecimal Surplusredmoney =redmoney.subtract (Curredmoney); if(Surplusminredmoney.compareto (Surplusredmoney) = = 1) {            returnfightluckredpacked (Redmoney, num, random, + +)errornum); }        returnCurredmoney; }     Public Static voidMain (string[] args) {System.out.println (Splitredpackes (NewBigDecimal ("100"), 20)); }}

Java Red Envelope rules