Guava BigIntegerMath类

BigIntegerMath提供BigInteger的实用方法。

类声明

以下是com.google.common.math.BigIntegerMath类的声明：

@GwtCompatible(emulated=true)
public final class BigIntegerMath
   extends Object

 方法

继承的方法

这个类继承了以下类方法：java.lang.Object

BigIntegerMath 示例

使用所选择的任何编辑器创建下面的java程序 C:/> Guava

GuavaTester.java

import java.math.BigInteger;
import java.math.RoundingMode;

import com.google.common.math.BigIntegerMath;

public class GuavaTester {

   public static void main(String args[]){
      GuavaTester tester = new GuavaTester();
      tester.testBigIntegerMath();
   }
   private void testBigIntegerMath(){
      System.out.println(BigIntegerMath.divide(BigInteger.TEN, new BigInteger("2"), RoundingMode.UNNECESSARY));
      try{
         //exception will be thrown as 100 is not completely divisible by 3 thus rounding
         // is required, and RoundingMode is set as UNNESSARY
         System.out.println(BigIntegerMath.divide(BigInteger.TEN, new BigInteger("3"), RoundingMode.UNNECESSARY));
      }catch(ArithmeticException e){
         System.out.println("Error: " + e.getMessage());
      }

      System.out.println("Log2(2): "+BigIntegerMath.log2(new BigInteger("2"), RoundingMode.HALF_EVEN));

      System.out.println("Log10(10): "+BigIntegerMath.log10(BigInteger.TEN, RoundingMode.HALF_EVEN));

      System.out.println("sqrt(100): "+BigIntegerMath.sqrt(BigInteger.TEN.multiply(BigInteger.TEN), RoundingMode.HALF_EVEN));

      System.out.println("factorial(5): "+BigIntegerMath.factorial(5));
   }
}

验证结果

使用javac编译器编译如下类

C:\Guava>javac GuavaTester.java

现在运行GuavaTester看到的结果

C:\Guava>java GuavaTester

看到结果

5
Error: Rounding necessary
Log2(2): 1
Log10(10): 1
sqrt(100): 10
factorial(5): 120