Separate number from a string

Question

I want to get the numbers of a given string and I used the code as below

String sample = "7011WD";
    String output = "";
    for (int index = 0; index < sample.length(); index++)
    {
        if (Character.isDigit(sample.charAt(index)))
        {
            char aChar = sample.charAt(index);
            output = output + aChar;
        }
    }

    System.out.println("output :" + output);

The Result is: output :7011

Is there any simple way to get the output?

Check with existing posts like this http://stackoverflow.com/questions/2367381/extract-numbers-from-a-string-java — Pandiyan Cool, Jul 25 '13 at 05:25

AllTooSir · Accepted Answer · 2013-07-25T04:43:12.077

6

Is there any simple way to get the output

May be you could use a regex \\D+ (D is anything which is not a digit , + means one or more occurence), and then String#replaceAll() all non-digits with empty string:

String sample = "7011WD";
String output = sample.replaceAll("\\D+","");

Though remember, using regex is not efficient at all . Also , this regex will remove the decimal points too !

You need to use Integer#parseInt(output) or Long#parseLong(output) to get the primitive int or long respectively.

You can also use Google's Guava CharMatcher. Specify the range using inRange() and return the characters from that range in sequence as a String using retainFrom().

edited Jul 25 '13 at 04:43

answered Jul 25 '13 at 04:27

AllTooSir

48,828
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130
164

1

If you're actually looking to get an integer, use Integer.parseInt(output) – wheresmycookie Jul 25 '13 at 04:29
@RobertKotcher Will add that ! – AllTooSir Jul 25 '13 at 04:30
I thought `\D` matches non-digit chars, could clarify please. – Cԃաԃ Jul 25 '13 at 04:33
Yes `replaceAll()` non-digits with empty string ! – AllTooSir Jul 25 '13 at 04:34

score 1 · Answer 2 · answered Jul 25 '13 at 05:01

1

Also you can use ASCII to do this

String sample = "7011WD";
String output = "";
for (int index = 0; index < sample.length(); index++)
{

        char aChar = sample.charAt(index);
        if(int(aChar)>=48 && int(aChar)<= 57)
        output = output + aChar;
    }
}

System.out.println("output :" + output);

answered Jul 25 '13 at 05:01

Shuhail Kadavath

448
3
13

OP asked for a simpler way to solve this problem, I'm not sure this follows those guidelines. – Tdorno Jul 25 '13 at 05:08

Separate number from a string

2 Answers2