显示正常数字而不是指数形式

Double a = 7.77d * 100000000; //Multiply Operation

System.out.println("Large multiply " + a.doubleValue());

System.out.println("Magic of big decimal " + BigDecimal.valueOf(a).setScale(0,RoundingMode.HALF_EVEN).toPlainString());

a = 7.77d / 100000; //Devide Operation

System.out.println("Devide operation " + a.doubleValue());

System.out.println("Magic of big decimal " + BigDecimal.valueOf(a).toPlainString());

DecimalFormat formatter = new DecimalFormat("0.000000");

System.out.println("Trimming the big string : "+formatter .format(a)); 

Large multiply 7.77E8

Magic of big decimal 777000000

Devide operation 7.769999999999999E-5

Magic of big decimal 0.00007769999999999999

Trimming the big string : 0.000078

double v = 1234567890123d;
Double d = new Double( v );

double

d.longValue();

toString

NumberFormat