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How to round and scale a number using DecimalFormat

I'm trying to to format a number using the DecimalFormat but the problem that I didn't get the expected result. Here is the problem:
I have this number: 1439131519 and I want to print only the five first digits but with a comma after 4 digits like this: 1439,1. I have tried to use DecimalFormat but it didn't work.
I tried like this but it dosen't work:
public static DecimalFormat format2 = new DecimalFormat("0000.0");
Anyone have an idea?

It is easier to do with maths rather than formatting.
Assuming your number is in a double:
double d = 1439131519;
d = d / 100000; // d = 14391,31519
d = Math.round(d) // d = 14391
d = d / 10; // d = 1439,1
Of course, you can do it in one line of code if you want. In using Math.round I am assuming you want to round to the nearest value. If you want to round down you can use Math.floor.
The comma is the normal decimal separator in much of Europe, so that might work by default in your locale. If not, you can force it by getting the formatter for a locale such as Germany. See: How to change the decimal separator of DecimalFormat from comma to dot/point?.

Java convert a format.String

I'm still new to Java and I was wondering if there are any ways to format to a double without having it rounded?
Example:
double n = 0.12876543;
String s = String.format("%1$1.2f", n);
If I were to print to the system, it would return the 0.13 instead of the precise 0.12. Now I have thought of a solution but I want to know if there is a better way of doing this. This my simple solution:
double n = 0.12876543;
double n = Double.parseDouble(String.format(("%1$1.2f", n));
Any other thoughts or solutions?

An elegant solution would be to use setRoundingMode with DecimalFormat. It sets the RoundingMode appropriately.
For example:
// Your decimal value
double n = 0.12876543;
// Decimal Formatting
DecimalFormat curDf = new DecimalFormat(".00");
// This will set the RoundingMode
curDf.setRoundingMode(RoundingMode.DOWN);
// Print statement
System.out.println(curDf.format(n));
Output:
0.12
Further, if you want to do additional formatting as a string you can always change the double value into string:
// Your decimal value
double n = 0.12876543;
// Decimal Formatting
DecimalFormat curDf = new DecimalFormat(".00");
// This will set the RoundingMode
curDf.setRoundingMode(RoundingMode.DOWN);
// Convert to string for any additional formatting
String curString = String.valueOf(curDf.format(n));
// Print statement
System.out.println(curString);
Output:
0.12
Please refer similar solution here: https://stackoverflow.com/a/8560708/4085019

As is, rounded to 2 decimals and truncated to 2 decimals :
double n = 0.12876543;
String complete = String.valueOf(n);
System.out.println(complete);
DecimalFormat df = new DecimalFormat("#.##");
String rounded = df.format(n);
System.out.println(rounded);
df.setRoundingMode(RoundingMode.DOWN);
String truncated = df.format(n);
System.out.println(truncated);
it displays :
0.12876543
0.13
0.12

Your example is working correctly in that it is properly rounding the number to 2 decimal places. 0.12876543 properly rounds to 0.13 when rounded to 2 decimal places. However, it seems like you always want to round the number down? If that is the case then you can do something like this...
public static void main(String[] args) throws IOException, InterruptedException {
double n = 0.12876543;
DecimalFormat df = new DecimalFormat("#.##");
df.setRoundingMode(RoundingMode.DOWN);
String s = df.format(n);
System.out.println(s);
}
This will print out a value of 0.12

Note first that a double is a binary fraction and does not really have decimal places.
If you need decimal places, use a BigDecimal, which has a setScale() method for truncation, or use DecimalFormat to get a String.

Set precision using decimalFormat error - Java

I am attempting to use the DecimalFormat java class for the first time, and I am running into a strange issue. I would like 125.295 to round to 125.30. I would think the format should automatically include the 0, but maybe I'm incorrect.
double num = 125.295;
DecimalFormat df = new DecimalFormat("#.##");
df.setRoundingMode(RoundingMode.HALF_UP);
String str = df.format(num);
System.out.println(str); //this is yielding 125.3 instead of 125.30
Please help and thank you in advance!

The DecimalFormat class treats '#' as "hide trailing zeroes" or '0' as "show the zeroes". As per the API for DecimalFormat:
0 Number Yes Digit
# Number Yes Digit, zero shows as absent
So you should use DecimalFormat("#.00") instead of DecimalFormat("#.##") if you want it to show trailing zeroes.

Try to use DecimalFormat like this:
double num = 125.295;
DecimalFormat df = new DecimalFormat("###.00");
System.out.println("sum (DecimalFormat) : " + df.format(num));
Output:
125.30

Formatting string number into double variable with two number after decimal point

I'm getting from server a string value formatted as follow: 14.5000
I need to create a double variable from it with two number after decimal point: 14.50. I've tried the following:
DecimalFormat df = new DecimalFormat("#,00");
Double priceD = Double.parseDouble((produitParam.item(paramNb).getTextContent()));
String dx = df.format(priceD);
produit.setPrixTtc(Double.valueOf(dx));
And I'm getting 14.5. If I use DecimalFormat("#.00"), it gives me 15...
Someone could help me with that ?

If you want string with precision upto 2 points after decimal you should use
DecimalFormat df = new DecimalFormat("#.00");
you have used "#,00"
',' is used for specifying grouping Separator.
for more information here is the Java Doc of DecimalFormat:
http://docs.oracle.com/javase/7/docs/api/java/text/DecimalFormat.html

you should look this link.There is a lot of answer your question.
I think.The best answer is DecimalFormat df = new DecimalFormat("#0.00");
for you in link
[how to convert double to 2 number after the dot?

Java: double: how to ALWAYS show two decimal digits

I use double values in my project and I would like to always show the first two decimal digits, even if them are zeros. I use this function for rounding and if the value I print is 3.47233322 it (correctly) prints 3.47. But when I print, for example, the value 2 it prints 2.0.
public static double round(double d) {
BigDecimal bd = new BigDecimal(d);
bd = bd.setScale(2, BigDecimal.ROUND_HALF_UP);
return bd.doubleValue();
}
I want to print 2.00!
Is there a way to do this without using Strings?
EDIT: from your answers (which I thank you for) I understand that I wasn't clear in telling what I am searching (and I'm sorry for this): I know how to print two digits after the number using the solutions you proposed... what i want is to store in the double value directly the two digits! So that when I do something like this System.out.println("" + d) (where d is my double with value 2) it prints 2.00.
I'm starting to think that there is no way to do this... right? Thank you again anyway for your answers, please let me know if you know a solution!

You can use something like this:
double d = 1.234567;
DecimalFormat df = new DecimalFormat("#.00");
System.out.print(df.format(d));
Edited to actually answer the question because I needed the real answer and this came up on google and someone marked it as the answer despite the fact that this wasn't going to work when the decimals were 0.

Use the java.text.NumberFormat for this:
NumberFormat nf= NumberFormat.getInstance();
nf.setMaximumFractionDigits(2);
nf.setMinimumFractionDigits(2);
nf.setRoundingMode(RoundingMode.HALF_UP);
System.out.print(nf.format(decimalNumber));

You can simply do this:
double d = yourDoubleValue;
String formattedData = String.format("%.02f", d);

DecimalFormat is the easiest option to use:
double roundTwoDecimals(double d) {
DecimalFormat twoDecimals = new DecimalFormat("#.##");
return Double.valueOf(twoDecimals.format(d));
}
Hope this solves your issue...

java.text.DecimalFormat df = new java.text.DecimalFormat("###,###.##");
df.setMaximumFractionDigits(2);
df.setMinimumFractionDigits(2);

You can use something like this:
If you want to retain 0 also in the answer:
then use (0.00) in the format String
double d = 2.46327;
DecimalFormat df = new DecimalFormat("0.00");
System.out.print(df.format(d));
The output: 2.46
double d = 0.0001;
DecimalFormat df = new DecimalFormat("0.00");
System.out.print(df.format(d));
The output: 0.00
However, if you use DecimalFormat df = new DecimalFormat("0.##");
double d = 2.46327;
DecimalFormat df = new DecimalFormat("0.##");
System.out.print(df.format(d));
The output: 2.46
double d = 0.0001;
DecimalFormat df = new DecimalFormat("0.##");
System.out.print(df.format(d));
The output: 0

I would just use something like:
System.out.printf("%.2f", theValueYouWantToPrint);
This gives you two decimals.