From c03a8c257537546bf753009d882a89d6a8a41992 Mon Sep 17 00:00:00 2001
From: longgui <1263913337@qq.com>
Date: Thu, 6 Aug 2020 21:29:28 +0800
Subject: [PATCH] =?UTF-8?q?=E5=8A=A0=E5=87=8F=E4=B9=98=E9=99=A4=E7=9A=84?=
 =?UTF-8?q?=E6=8E=A5=E5=8F=A3?=
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---
 加减乘除代码.java | 39 +++++++++++++++++++++++++++++++++++++++
 1 file changed, 39 insertions(+)
 create mode 100644 加减乘除代码.java

diff --git a/加减乘除代码.java b/加减乘除代码.java
new file mode 100644
index 0000000..c44996e
--- /dev/null
+++ b/加减乘除代码.java
@@ -0,0 +1,39 @@
+
+public class Arith
+{
+	//默认除法运算精度
+	private static final int DEF_DIV_SCALE = 10;
+	//构造器私有化，让这个类不能实例化
+	private Arith(){}
+	//提供精确的加法运算
+	public static double add(double v1, double v2)
+	{
+		BigDecimal b1 = BigDecimal.valueOf(v1);
+		BigDecimal b2 = BigDecimal.valueOf(v2);
+		return b1.add(b2).doubleValue();
+	}
+	//精确的减法运算
+	public static double sub(double v1, double v2)
+	{
+		BigDecimal b1 = BigDecimal.valueOf(v1);
+		BigDecimal b2 = BigDecimal.valueOf(v2);
+		return b1.subtract(b2).doubleValue();
+	}
+	//精确的乘法运算
+	public static double mul(double v1, double v2)
+	{
+		BigDecimal b1 = BigDecimal.valueOf(v1);
+		BigDecimal b2 = BigDecimal.valueOf(v2);
+		return b1.multiply(b2).doubleValue();
+	}
+	//提供（相对）精确的除法运算，当发生除不尽的情况时
+	//精确到小数点后10位的数字四舍五入
+	public static double div(double v1, double v2)
+	{
+		BigDecimal b1 = BigDecimal.valueOf(v1);
+		BigDecimal b2 = BigDecimal.valueOf(v2);
+		return b1.divide(b2, DEF_DIV_SCALE, BigDecimal.ROUND_HALF_UP).doubleValue();
+	}	
+	
+
+}
\ No newline at end of file