init

ruoyi-cai/src/main/java/com/ruoyi/cai/util/NumCaUtil.java

@@ -0,0 +1,20 @@
+package com.ruoyi.cai.util;
+
+import cn.hutool.core.util.NumberUtil;
+
+import java.math.BigDecimal;
+import java.math.RoundingMode;
+
+public class NumCaUtil {
+
+    /**
+     * 向下取整计算金额
+     * @param value
+     * @param rate
+     * @return
+     */
+    public static Long coin(Long value, BigDecimal rate){
+        BigDecimal decimal = NumberUtil.mul(value, rate);
+        return decimal.setScale(0, RoundingMode.DOWN).longValue();
+    }
+}