Guava LongMath类
LongMath 是用来对Long值进行数学运算。基本的独立数学函数根据涉及的主要数字类型分为IntMath、LongMath、DoubleMath和BigIntegerMath类。这些类具有平行结构，但每个类只支持相关的函数子集。
声明 : com.google.common.math.LongMath类的声明是 :
@GwtCompatible(emulated = true)public final class LongMath extends Object
下表显示了Guava的LongMath类提供的一些方法。
异常 :
Guava的LongMath类提供的一些其他方法是。
例子1 :
// Java code to show implementation of// LongMath Class of Guavaimport java.math.RoundingMode;import com.google.common.math.LongMath; class GFG { // Driver code public static void main(String args[]) { // Creating an object of GFG class GFG obj = new GFG(); // Function calling obj.examples(); } private void examples() { try { // exception will be thrown as 80 is not // completely divisible by 3 // thus rounding is required, and // RoundingMode is set as UNNESSARY System.out.println(LongMath.divide(80, 3, RoundingMode.UNNECESSARY)); } catch (ArithmeticException ex) { System.out.println("Error Message is : " + ex.getMessage()); } }}
输出:
Error Message is : mode was UNNECESSARY, but rounding was necessary
例子2 :
// Java code to show implementation of// LongMath Class of Guavaimport java.math.RoundingMode;import com.google.common.math.LongMath; class GFG { // Driver code public static void main(String args[]) { // Creating an object of GFG class GFG obj = new GFG(); // Function calling obj.examples(); } private void examples() { // As 120 is divisible by 4, so // no exception is thrown System.out.println(LongMath.divide(120, 4, RoundingMode.UNNECESSARY)); // To compute GCD of two integers System.out.println("GCD is : " + LongMath.gcd(70, 14)); // To compute log to base 10 System.out.println("Log10 is : " + LongMath.log10(1000, RoundingMode.HALF_EVEN)); // To compute remainder System.out.println("modulus is : " + LongMath.mod(125, 5)); // To compute factorial System.out.println("factorial is : " + LongMath.factorial(7)); // To compute log to base 2 System.out.println("Log2 is : " + LongMath.log2(8, RoundingMode.HALF_EVEN)); // To compute square root System.out.println("sqrt is : " + LongMath.sqrt(LongMath.pow(12, 2), RoundingMode.HALF_EVEN)); }}
输出:
30GCD is : 14Log10 is : 3modulus is : 0factorial is : 5040Log2 is : 3sqrt is : 12
参考资料 :Google Guava
