Java Lottery snapping algorithm _java

This example for you to share the Java Lottery snapping algorithm for everyone to refer to, the specific contents are as follows

Application Scenarios

Single-piece trophy snapping (limited)
Multiple prizes are awarded according to Probability (limited, limited)

Code implementation

Table structure:

--Lottery Set
CREATE TABLE Award_info
(ID number (one) not     null,
 act_id number (one   ),  --Activity ID
 NUM    Number (one)--total number of  prizes (0 is unlimited)
 REST number    (one)-  -Prize margin
 odds number    (one) default 0,  --Jackpot Probability
 start_date date,     --Start date (nullable) end_date date  ,     --End Date (nullable) product_id number
 ( One)  --Trophy ID
 State number   (5) Default 0,  --Status 0-valid 1-fail
 info_type number (5) default 0   --0 -Normal 
);
ALTER TABLE Award_info
 add constraint Pk_award_info primary key (ID);

--Jackpot Record
CREATE TABLE Award_log
(ID number (one     ),  
 act_id number (one   ),  --Activity ID
 get_time  Date,  --Jackpot Time
 product_id number (one)-  -Trophy ID
 num number    (one) default 1, -  -Jackpot number   person varchar2,--winner (
 info_id)-  -lottery set ID
 state Number   (5)  --state 0-Valid 1-invalid
);
ALTER TABLE Award_log
 add constraint Pk_award_log primary key (ID);

Code:

  public static class awardresult{public int ret; Returns the result public int logid; Award_log ID}/** * lottery algorithm * @param actid lottery Activity ID * @param person Lottery * @param productId prize ID-1 is the activity ID  There are prizes * @param Excludeid excluding prizes ID-1 is not excluded, and ProductID can not be >0 * @param checkdate whether the check time * @return-1 no lottery data;-2 prizes have been drawn out; -3 other errors; >=0 winning ProductID; -4 Exclude ID * @throws Exception/public static awardresult getawardfull (int actid, String person, int productId, int 

    [] Excludeids, Boolean checkdate) throws sqlexception{awardresult result = new Awardresult ();
    Connection conn = Jdbc.getconnection ();
    Conn.setautocommit (FALSE);
      try{list<map<string,object>> rows;
      String SQL;
      String checkdatestr = ""; String basesql = "Select T.id, t.product_id, T.num, T.rest, T.odds, t.info_type from Award_info t where t.act_id=?"
      and t.state=0 "; if (checkdate) {checkdatestr = "and T.start_date <= sysdate and T.end_date >= Sysdate ";
        } if (ProductId > 0) {//snapping up sql = Basesql + "and t.product_id=?" + Checkdatestr + "for update";
      rows = jdbc.getrows (sql, New Object[]{actid, productId}, conn);
        }else{//activities all items Draw sql = Basesql + checkdatestr + "for update";
      rows = jdbc.getrows (sql, New Object[]{actid}, conn);  } if (Rows.isempty ()) {//No lottery data log.info ("No Raffle Data actid={} person={} productid={} excludeids={}".
        Actid, person, productId, Excludeids, checkdate);
        Conn.commit ();
        Result.ret =-1;
      return result;
      int infoid =-1;
      int getproductid =-1;
      int num =-1;
      int rest =-1;
        if (rows.size () = = 1) {//Snapping num = ((number) rows.get (0). Get ("num")). Intvalue ();
        Rest = ((number) rows.get (0). Get ("REST")). Intvalue ();
        Infoid = ((number) rows.get (0). Get ("ID"). Intvalue ();
      GetProductID = ((number) rows.get (0). Get ("product_id"). Intvalue ();
   }else{//Lottery     int[][] temp = new Int[rows.size ()][3];
        int sum =-1;
        int i = 0;
          for (int k = 0; k < rows.size (); k++) {//Set prize pool int odds = ((BigDecimal) Rows.get (k). Get ("odds")). Intvalue ();
          sum++; Temp[i][0] = sum;
          Start value sum = SUM + odds; TEMP[I][1] = sum;  End value temp[i][2] = k;
        Rows index i++;

        }//Draw Random Random = new Random ();
        int r = random.nextint (sum + 1);
        int j = 0;
            for (int k = 0; k < i; k++) {if (R >= temp[k][0] && r <= temp[k][1]) {j = k;
          Break
        } infoid = ((BigDecimal) Rows.get (temp[j][2)). Get ("ID"). Intvalue ();
        GetProductID = ((BigDecimal) Rows.get (temp[j][2)). Get ("product_id"). Intvalue ();
        num = ((number) Rows.get (temp[j][2]). Get ("NUM"). Intvalue ();
      Rest = ((number) Rows.get (temp[j][2]). Get ("REST"). Intvalue (); //Decide whether to exclude ID if(Arrayutils.contains (Excludeids, GetProductID)) {Log.info ("is exclusion ID actid={} person={} productid={} excludeids={} checkdate={}", Actid, Person, productId, Excludeid
        s, checkdate);
        Conn.commit ();
        Result.ret =-4;
      return result; ///stock less if (num > 0 && rest <= 0) {log.info ("prize emptied actid={} person={} productid={} excl"
        udeids={} checkdate={} ", Actid, Person, productId, Excludeids, checkdate);
        JDBC.COMMIT (conn);
        Result.ret =-2;
      return result;
        //Update prize record if (num > 0) {//non-unlimited sql = "Update award_info set rest = rest-1 where id =?";
      Jdbc.update (SQL, New object[]{infoid}, conn);
      //Record winning list Awardlog log = new Awardlog ();
      Log.setactid (Actid);
      Log.setnum (1);
      Log.setperson (person);
      Log.setproductid (GetProductID);
      Log.setinfoid (infoid);
      Number Logid = Log.save (conn); if (Logid = = null) {throw new Sqlexception ("Save Award_log Error");

      } Result.logid = Logid.intvalue ();
      Conn.commit ();
      Result.ret = GetProductID;

    return result;
      }catch (SQLException e) {log.error ("Getaward error", E);
    Conn.rollback ();
    }finally{Jdbc.close (conn);
    } Result.ret =-3;
  return result;

 }

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