用于 BigDecimal 和原始数据类型之间的算术运算的Java程序

在财务计算中使用的浮点数据类型（float 和 double）不太准确。因此， Java提供了一个单独的类“BigDecimal”来执行操作并避免计算中出现错误的最小机会。 BigDecimal 类为算术、比例处理、舍入、比较、格式转换和散列提供对双数的操作。它可以非常精确地处理非常大和非常小的浮点数，但稍微补偿了时间复杂度。 BigDecimal 提供了许多要实现的方法。在本文中，我们将讨论可以在 BigDecimal 上执行的基本算术运算，以及在 BigDecimal 和原始数据类型（如 int、short、long 等）之间执行相同的运算。

示例 1：

Java

// Java Program to Add, Subtract and Multiply
// Two big decimal numbers 
 
// Importing input output classes
import java.io.*;
 
// Importing BigDecimal class from
// java.math package
import java.math.BigDecimal;
 
// Main class
class GFG {
 
    // Main driver method
    public static void main(String[] args)
    {
 
        // Declaring two variables of type BigDecimal
        // Custom numbers for illustration
        BigDecimal num1 = new BigDecimal("15.3514628768");
        BigDecimal num2 = new BigDecimal("45.37844");
 
        // Mathematic operation over two numbers
 
        // Addition using add() method
        System.out.println("Addition of num1 and num2 = "
                           + (num1.add(num2)));
 
        // Subtraction using subtract() method
        System.out.println("Subtraction of num1 and num2 = "
                           + (num1.subtract(num2)));
 
        // Multiplication using multiply() method
        System.out.println(
            "Multiplication of num1 and num2 = "
            + (num1.multiply(num2)));
    }
}

输出

Addition of num1 and num2 = 60.7299028768
Subtraction of num1 and num2 = -30.0269771232
Multiplication of num1 and num2 = 696.625437067096192

输出说明：

请注意，操作的准确性非常高。现在对以下示例中的同一组数字执行除法，如下所示：

示例 2：

Java

// Java Program to show exception thrown if blunt division
// of two big decimal numbers is carried on
 
// Importing input output classes
import java.io.*;
// Importing BigDecimal class from
// java.math package
import java.math.BigDecimal;
 
// Main class
class GFG {
   
    // Main driver method
    public static void main (String[] args) {
       
        // Creating an object of VigDecimal class and
        // initializing the big decimal values
        // Custom entry 
        BigDecimal num1 = new BigDecimal("15.3514628768");
        BigDecimal num2 = new BigDecimal("45.37844");
       
        // Division over two numbers
        // using divide() method and printing the resultant number
        System.out.println("Division of num1 and num2 = " + (num2.divide(num1)));
    }
}

输出：

输出说明：

出现这个错误是因为两个数字的除法是非终止的，我们知道引入 BigDecimal 是为了提供最大的精度。因此，它会产生错误。我们将在下一个代码中纠正相同的问题，我们将除以相同的数字，但现在数据类型是 double，它应该不会产生任何错误并给出一些答案。

示例 3：

Java

// Java Program to show division of two big decimal numbers
 
// Importing input output classes
import java.io.*;
 
// Main class
class GFG {
 
    // Main driver method
    public static void main(String[] args)
    {
 
        // Creating and initializing double numbers
        // Custom entries
        double num1 = 15.3514628768;
        double num2 = 45.37844;
 
        // Dividing two big decimal numbers after which
        // numbers obtained will also be a big decimal
        // number
 
        // Print and display the resultant number
        System.out.println("Division of num1 and num2 = "
                           + (num2 / num1));
    }
}

输出

Division of num1 and num2 = 2.955968454874647

Until now, we’ve performed the arithmetic operations on two BigDecimal objects, and now we shall try to do the same thing with the primitive data types.So here we go.

示例 4：

Java

// Java Program to Add big decimal number
// with an Integer number
 
// Importing input output classes
import java.io.*;
 
// importing BigDecimal class from
// java.math package
import java.math.BigDecimal;
 
// main class
class GFG {
 
    // Main driver method
    public static void main(String[] args)
    {
 
        // Declaring a BigDecimal object
        BigDecimal num1 = new BigDecimal("12");
 
        // Declaring an integer number
        int num2 = 15;
 
        // Adding a big decimal number with
        // an integer number
        System.out.println("Addition of num1 and num2 ="
                           + num1.add(num2));
    }
}

输出：

输出说明：

这是因为 BigDecimal 只允许对 BigDecimal 对象执行操作。因此，我们需要使用 BigDecimal Class 的构造函数将我们的原始数据类型变量转换为 BigDecimal 的对象。上面的冲突在下面的代码中解决如下。

示例 5：

Java

// Java Program to Add big decimal number
// with an Integer number
 
// Importing input output classes
import java.io.*;
 
// Importing BigDecimal class from
// java.math package
import java.math.BigDecimal;
 
// Main class
class GFG {
 
    // Main driver method
    public static void main(String[] args)
    {
 
        // Declaring a BigDecimal object
        BigDecimal num1 = new BigDecimal("12");
 
        // Declaring an integer number
        int num2 = 15;
 
        // Print the addition of two numbers
        System.out.println(
            "Addition of num1 and num2 = "
            + num1.add(new BigDecimal(num2)));
    }
}

输出

Addition of num1 and num2 = 27

输出说明：

这里发生的事情是我们正在创建一个类 BigDecimal 的新对象，其值与 num2 相同，我们直接将通过构造函数创建的对象传递给 add() 方法的参数。我们得到了所需的答案。 BigDecimal 和 int 之间的算术运算如下所示。

示例 6：

Java

// Importing all input output classes
import java.io.*;
// Importing BigDecimal class from
// java.math package
import java.math.BigDecimal;
 
// Main class
class GFG {
 
    // Main driver method
    public static void main(String[] args)
    {
 
        // Declaring a BigDecimal object
        BigDecimal num1 = new BigDecimal("12");
 
        // Declaring an integer number
        int num2 = 15;
 
        // Addition over numbers
        // Print the resultant desired number
        System.out.println(
            "Addition of num1 and num2 = "
            + num1.add(new BigDecimal(num2)));
 
        // Subtraction over numbers
        // Print the resultant desired number
        System.out.println(
            "Subtraction of num1 and num2 = "
            + num1.subtract(new BigDecimal(num2)));
 
        // Multiplication over numbers
        // Print the resultant desired number
        System.out.println(
            "Multiplication of num1 and num2 = "
            + num1.multiply(new BigDecimal(num2)));
 
        // Division over numbers
        // Print the resultant desired number
        System.out.println(
            "Division of num1 and num2 = "
            + num1.divide(new BigDecimal(num2)));
    }
}

输出

Addition of num1 and num2 = 27
Subtraction of num1 and num2 = -3
Multiplication of num1 and num2 = 180
Division of num1 and num2 = 0.8