java.math.BigInteger_100的阶乘的实现

/*100的阶乘
* @src  http://eric-619.iteye.com/admin/blogs/693211
* java.math.BigInteger 高精度数据类型
*/

import java.math.BigInteger;


public class TestYiBai {

public static void main(String[] args) {
   System.out.println(new TestYiBai().big(BigInteger.valueOf(100)).toString());
  
}

/* 基础数据类型对象化
* 基础数据类型转化为相应的包装对象之间的四则运算
* 加：o.add(Object o1)
* 减：o.subtract(Object o1)
* 乘：o.multiply(Object o1)
* 除：o.divide(Object o1)
*/
public BigInteger big(BigInteger b){
   if(b.equals(BigInteger.valueOf(1L))){
    return BigInteger.valueOf(1L);
   }else{
      return (b.multiply(big(b.subtract(BigInteger.valueOf(1L)))));     
   }
}
}