About NumberFormat question

Question

import java.util.*;
import java.text.*;
public class TestPrintf{
public static void main(String[] args) {
String[] num = {
"123.3105",
"123.3115",
"123.3125",
"123.3135",
"123.3145",
"123.3155",
"123.3165",
"123.3175",
"123.3185",
"123.3195"
NumberFormat nf;
nf = NumberFormat.getInstance();
nf.setMinimumIntegerDigits (nf.getMinimumIntegerDigits());
nf.setMinimumFractionDigits (3);
nf.setMaximumFractionDigits (3);
nf.setGroupingUsed (false);
for(int i=0;i<num.length;i++){
System.out.println(num[i] +" ,NumberFormat "+nf.format (Double.valueOf(num).doubleValue()));
out is:
123.3105 ,NumberFormat 123.310
123.3115 ,NumberFormat 123.312
123.3125 ,NumberFormat 123.312
123.3135 ,NumberFormat 123.314
123.3145 ,NumberFormat 123.314
123.3155 ,NumberFormat 123.316
123.3165 ,NumberFormat 123.316
123.3175 ,NumberFormat 123.318
123.3185 ,NumberFormat 123.318
123.3195 ,NumberFormat 123.320
I want to know, when last number is "5", number before "5" is "0" "2" "4" "6" "8",why "5" will be cut ,and "1" "3" "5" "7" "9" will add 1
how to rewrite this java code, and make result as
123.3105 ,NumberFormat 123.310
123.3115 ,NumberFormat 123.312
123.3125 ,NumberFormat 123.313
123.3135 ,NumberFormat 123.314
123.3145 ,NumberFormat 123.315
123.3155 ,NumberFormat 123.316
123.3165 ,NumberFormat 123.317
123.3175 ,NumberFormat 123.318
123.3185 ,NumberFormat 123.319
123.3195 ,NumberFormat 123.320
thanks!
[email protected]

Answer 1

import java.util.*;
import java.text.*;
public class TestPrintf {
    public static void main(String[] args) {
        String[] num = {
            "123.3105",
            "123.3115",
            "123.3125",
            "123.3135",
            "123.3145",
            "123.3155",
            "123.3165",
            "123.3175",
            "123.3185",
            "123.3195"
        NumberFormat nf;
        nf = NumberFormat.getInstance();
        nf.setMinimumIntegerDigits (nf.getMinimumIntegerDigits());
        nf.setMinimumFractionDigits (3);
        nf.setMaximumFractionDigits (3);
        nf.setGroupingUsed (false);
        for(int i=0;i<num.length;i++) {
            System.out.println(num[ i ] +" ,NumberFormat "+nf.format (Double.valueOf(num[ i ]).doubleValue() + 0.0001));
}This prints:
123.3105 ,NumberFormat 123,311
123.3115 ,NumberFormat 123,312
123.3125 ,NumberFormat 123,313
123.3135 ,NumberFormat 123,314
123.3145 ,NumberFormat 123,315
123.3155 ,NumberFormat 123,316
123.3165 ,NumberFormat 123,317
123.3175 ,NumberFormat 123,318
123.3185 ,NumberFormat 123,319
123.3195 ,NumberFormat 123,320
I guess that is what you meant (note: first number prints 123,311 instead of 123,310).
Jesper