BigDecimal用法大全及注意事项

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BigDecimal a = new BigDecimal("10");
BigDecimal b = new BigDecimal("5");
BigDecimal add = a.add(b);//加
BigDecimal subtract= a.subtract(b);//减
BigDecimal multiply= a.multiply(b);//乘
BigDecimal divide=a.divide(b);//除

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	BigDecimal a = new BigDecimal("12.123456");
    BigDecimal b=a.setScale(2, BigDecimal.ROUND_HALF_UP);//设置2位小数，并四舍五入
    System.out.println(b);

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	BigDecimal a = new BigDecimal("10");
    BigDecimal b = new BigDecimal("5");
    System.out.println( "a大于b："+( a.compareTo(b)>0 ) );
    System.out.println( "a小于b："+( a.compareTo(b)<0 ) );
    System.out.println( "a大于等于b："+( a.compareTo(b)>=0 ) );
    System.out.println( "a小于等于b："+( a.compareTo(b)<=0 ) );

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BigDecimal a = new BigDecimal("0");
BigDecimal b = new BigDecimal("0");
System.out.println( "a等于0："+( a.compareTo(new BigDecimal("0")) ==0 ) );  
System.out.println( "b等于0："+( b.compareTo(BigDecimal.ZERO) ==0 ) ); // 以上这两种都可以

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BigDecimal a = new BigDecimal("12.150");
BigDecimal b = new BigDecimal(12.150);
System.out.println(a);
System.out.println(b);

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double d =14.2;
BigDecimal e=new BigDecimal(d);
System.out.println(e);

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double d =14.2;
BigDecimal e=new BigDecimal(d);
BigDecimal f=new BigDecimal(d+"" );