BillUtils.java
1.54 KB
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/*
* Copyright Codecrew Ry
*
* All rights reserved.
*
* This license applies to any software containing a notice placed by the
* copyright holder. Such software is herein referred to as the Software.
* This license covers modification, distribution and use of the Software.
*
* Any distribution and use in source and binary forms, with or without
* modification is not permitted without explicit written permission from the
* copyright owner.
*
* A non-exclusive royalty-free right is granted to the copyright owner of the
* Software to use, modify and distribute all modifications to the Software in
* future versions of the Software.
*
*/
package fi.codecrew.moya.utilities;
public class BillUtils {
private static final int[] multipliers = new int[] { 7, 3, 1 };
/**
* Calculates and return the reference number calculated from the given base
*
* @param base
*/
public static Integer createReferenceNumber(Integer base) {
return base * 10 + calculateChecksum(base);
}
/**
* This function will calculate the checksum for the bills checksum nuber
* for the given checksum base
*
* @param base
* The base of the checksum
* @return checksum integer in the range of 0-9 calculated from the given
* base
*/
public static Integer calculateChecksum(Integer base)
{
int checksum = 0;
for (int i = 0; base > 0; i++) {
int num = base % 10;
checksum += multipliers[i % multipliers.length] * num;
base = base / 10;
}
return (checksum % 10 == 0 ? 0 : 10 - (checksum % 10));
}
}