Javaデジタル処理ツールクラス

package com.vince;

import java.math.BigDecimal;
import java.math.BigInteger;
import java.text.DecimalFormat;
import java.util.Arrays;

/**
 * 1.Biginteger:     Integer        
 * 
 *     :public Biginteger(String var)
 * 
 *     ：
 * 		System.out.println(b1.add(b2));			//+
		System.out.println(b1.subtract(b2));	//-
		System.out.println(b1.multiply(b2));	 //*
		System.out.println(b1.divide(b2));		// /
		System.out.println(b1.remainder(b2));	// %
		
		System.out.println(Arrays.toString(b1.divideAndRemainder(b2)));// /and%
	
	2.Bigdecimal:        ,float   double     ，        ，  
	   ，java   BigDecimal,    ，            。
	    ：public BigDecimal(String val);
	
		double pi=3.1415927;
		//     
		System.out.println(new DecimalFormat("0").format(pi));
		System.out.println(new DecimalFormat("0.00").format(pi));
		System.out.println(new DecimalFormat("00.00").format(pi));
		System.out.println(new DecimalFormat("#").format(pi));
		System.out.println(new DecimalFormat("#.##%").format(pi));
 *
 */
public class Test1 {

	public static void main(String[] args) {
		//     
		String val1="135745641687897785";
		String val2="245687568855569845";
		BigInteger b1=new BigInteger(val1);
		BigInteger b2=new BigInteger(val2);
		
		System.out.println(b1.add(b2));			//+
		System.out.println(b1.subtract(b2));	//-
		System.out.println(b1.multiply(b2));	 //*
		System.out.println(b1.divide(b2));		// /
		System.out.println(b1.remainder(b2));	// %
		
		System.out.println(Arrays.toString(b1.divideAndRemainder(b2)));// /and%
		
		String val3="56129.145656789";
		String val4="698.12545455485578";
		BigDecimal b3=new BigDecimal(val3);
		BigDecimal b4=new BigDecimal(val4);
		System.out.println(b3.add(b4));			//+
		System.out.println(b3.subtract(b4));	//-
		System.out.println(b3.multiply(b4));	 //*
		
		//System.out.println(b3.divide(b4));		//             ，       
		//System.out.println(b1.remainder(b2));	// %
		//System.out.println(b3.scale()-b4.scale());
		
		double pi=3.1415927;
		//     
		System.out.println(new DecimalFormat("0").format(pi));
		System.out.println(new DecimalFormat("0.00").format(pi));
		System.out.println(new DecimalFormat("00.00").format(pi));
		System.out.println(new DecimalFormat("#").format(pi));
		System.out.println(new DecimalFormat("#.##%").format(pi));
		
		long num=216541752;
		System.out.println(new DecimalFormat("###,###").format(num));//     
	}

}