j02060501.java

经典java教材《java完美经典》一书中源码的完全收集

import java.lang.*;
import java.math.*;  //要使用 BigInteger 和 BigDecimal

class j02060501
{
  public static void main(String para[])
  {
 		BigInteger BInt1 = new  BigInteger("22222222222222222222");
 		BigInteger BInt2 = new  BigInteger("33333333333333333333");
 		System.out.println( "BInt1 值 = " + BInt1.toString() ); 
 		System.out.println( "BInt2 值 = " + BInt2 ); // 也可印出
 		System.out.println( "BInt1.longValue() = " + BInt1.longValue() );
 		
 		String result = BInt1.multiply(BInt2).toString();
 		System.out.println( "BInt1 值 * Bint2 值 = " + result );
 		result = BInt1.divide(BInt2).toString();
 		System.out.println( "BInt1 值 / Bint2 值 = " + result );
 		
 		switch( BInt1.compareTo(BInt2))
 		{
 			case -1:
 				System.out.println("BInt1 之值 < BInt2 之值" );
 				break;
 			case 0:
 				System.out.println("BInt1 之值 == BInt2 之值" );
 				break;
 			case 1:
 				System.out.println("BInt1 之值 > BInt2 之值" ); 			
 		} 				
 		System.out.println( "================================" );
 		
 		BInt2 = BInt1.subtract( BInt2 );  //BInt2 = BInt1 - BInt2
 		System.out.println( "BInt2 值 = " + BInt2 ); // 也可印出
 	  BigDecimal BDec1 = new BigDecimal( BInt2 );
 	  BigDecimal BDec2 = new BigDecimal( "98335663689000423.543566" );
 		System.out.println( "BDec1 值 = " + BDec1 ); 
 		System.out.println( "BDec2 值 = " + BDec2 ); 
 		result = BDec1.divide(BDec2,10,BigDecimal.ROUND_HALF_UP).toString();   
 		                       //除，取到小数点10位，四舍五入	
		System.out.println( "BDec1 值 / BDec2 值 = " + result );
  }
}