Java BigDecimal valueOf（）方法与示例

BigDecimal类的valueOf()方法 (BigDecimal Class valueOf() method)

Syntax:

句法：

    public static BigDecimal valueOf (double d);
    public static BigDecimal valueOf (long l);
    public static BigDecimal valueOf (long unsc_val , int sc_val);

• valueOf() method is available in java.math package.

  valueOf()方法在java.math包中可用。

• valueOf (double d) method is used to convert the given double value into a BigDecimal.

  valueOf(double d)方法用于将给定的double值转换为BigDecimal。

• valueOf (long l) method is used to convert the given long value into a BigDecimal.

  valueOf(long l)方法用于将给定的long值转换为BigDecimal。

• valueOf (long unsc_val , int sc_val) method is used to convert the given long unscaled value and an integer value into a BigDecimal.

  valueOf(long unsc_val，int sc_val)方法用于将给定的long非标度值和一个整数值转换为BigDecimal。

• These methods may throw an exception at the time of returning the value of the given parameter.

  这些方法在返回给定参数的值时可能会引发异常。

  NumberFormatException: This exception may throw when the given parameter is not finite.

  NumberFormatException ：如果给定参数不是有限的，则可能引发此异常。

• These are non-static methods and it is accessible with class objects and if we try to access these methods with the class name then we will get an error.

  这些是非静态方法，可通过类对象访问，如果尝试使用类名访问这些方法，则会收到错误消息。

Parameter(s):

参数：

• In the first case, valueOf(double d),

  在第一种情况下， valueOf(double d) ，

  • double d – represents the double value to be converted to a BigDecimal.
  • double d –表示要转换为BigDecimal的double值。

• In the first case, valueOf (long l),

  在第一种情况下， valueOf(long l) ，

  • long l – represents the long value to be converted to a BigInteger.
  • long l –表示要转换为BigInteger的long值。

• In the first case, valueOf (long unsc_val, int sc_val),

  在第一种情况下， valueOf(long unsc_val，int sc_val) ，

  • long unsc_val – represents the unscaled value of this BigDecimal.
  • long unsc_val –表示此BigDecimal的未缩放值。
  • int sc_val – represents the scale of this BigDecimal.
  • int sc_val –表示此BigDecimal的小数位数 。

Return value:

返回值：

In all the cases, the return type of the method is BigDecimal,

在所有情况下，方法的返回类型为BigDecimal 。

• In the first case, it returns the converted double value to a BigDecimal.

  在第一种情况下，它将转换后的double值返回给BigDecimal。

• In the second case, it returns the converted long value to a BigDecimal.

  在第二种情况下，它将转换后的long值返回给BigDecimal。

• In the third case, it returns the BigDecimal and its value is calculated by using [(unsc_val) * 10 pow (-sc)].

  在第三种情况下，它返回BigDecimal，并使用[[unsc_val)* 10 pow(-sc)]计算其值。

Example:

例：

// Java program to demonstrate the example 
// of valueOf() method of BigDecimal

import java.math.*;

public class ValueOfOfBD {
    public static void main(String args[]) {
        // Instantiates three variables l_val
        // d_val, unscale_val
        long l_val = 125487312456l;
        double d_val = 1245871.12345;
        long unscale_val = 123458745123l;

        // converts the given long value into
        // a BigDecimal and store it in a variable
        // named value_of
        BigDecimal value_of = BigDecimal.valueOf(l_val);

        System.out.println("l_val: " + l_val);
        System.out.println("valueOf(long): ");

        // Display value_of
        System.out.println("BigDecimal.valueOf(l_val): " + value_of);

        System.out.println();

        // converts the given double value into
        // a BigDecimal and store it in a variable
        // named value_of
        value_of = BigDecimal.valueOf(d_val);

        System.out.println("d_val: " + d_val);
        System.out.println("valueOf(double): ");

        // Display value_of
        System.out.println("BigDecimal.valueOf(d_val): " + value_of);

        System.out.println();

        // converts the given unscaled long value
        // with the given scale into a BigDecimal and
        // store it in a variable named value_of
        value_of = BigDecimal.valueOf(unscale_val, 5);

        System.out.println("unscale_val: " + unscale_val);
        System.out.println("valueOf(long,int): ");

        // Display value_of
        System.out.println("BigDecimal.valueOf(unscale_val,5): " + value_of);
    }
}

Output

输出量

l_val: 125487312456
valueOf(long): 
BigDecimal.valueOf(l_val): 125487312456

d_val: 1245871.12345
valueOf(double): 
BigDecimal.valueOf(d_val): 1245871.12345

unscale_val: 123458745123
valueOf(long,int): 
BigDecimal.valueOf(unscale_val,5): 1234587.45123

翻译自: https://www.includehelp.com/java/bigdecimal-valueof-method-with-example.aspx