Using regular expression (String + number) in Scala

Question

I am using regression expression to find the patterns such as:

"Today USER ID: 123556 cancelled"
"January USER ID: 236477 renewed"
"February USER ID: 645689 dispute"

Basically I am looking for the string contains "USER ID: " + number. I am using the following code, but it couldn't match anything. Could anyone please give some suggestions?

if (myString.matches("USER ID: ([0-9]+)")) {
      println(a)
}

string.matches("^.*USER ID: ([0-9]+).*$") will match what you have edited the question to — GregH
– GregH, Commented Jun 2, 2015 at 19:55

GregH · Accepted Answer · 2015-06-02 19:55:15Z

4

It should just be:

if (myString.matches("^USER ID: ([0-9]+)$")) {

without the slashes in the regex string and with a space after USER ID:

just tested and it worked for me as follows:

String string =  "USER ID: 12345";
if(string.matches("^USER ID: ([0-9]+)$")){
     System.out.println("matches");
}

There are lots of good "regex cheatsheets" out there. You can find one such here: http://www.cheatography.com/davechild/cheat-sheets/regular-expressions/

edited Jun 2, 2015 at 19:55

answered Jun 2, 2015 at 19:24

GregH

5,53112 gold badges62 silver badges115 bronze badges

Sign up to request clarification or add additional context in comments.

2 Comments

Edamame Over a year ago

Just noticed that I have char before and after my pattern, e.g. "January USER ID: 12345 cancelled". Then it doesn't seem to work ... is there any additional modification required? Thanks!

GregH Over a year ago

string.matches("^.*USER ID: ([0-9]+).*$") will match what you have edited the question to

vks · Accepted Answer · 2015-06-02 19:12:29Z

1

^USER ID: ([0-9]+)$

        ^^

You are missing this space.

answered Jun 2, 2015 at 19:12

vks

68.1k11 gold badges96 silver badges132 bronze badges

3 Comments

Edamame Over a year ago

Hi, I just added the space, using "/^USER ID: ([0-9]+)$/" still doesn't work

resueman Over a year ago

@Edamame use ^USER ID: ([0-9]+)$, not /^USER ID: ([0-9]+)$/

Edamame Over a year ago

Thanks. Just noticed that I have char before and after my pattern, e.g. "January USER ID: 12345 cancelled". So I modified it to ".USER ID: ([0-9]+)." But the . char doesn't seem to work right, am I missing anything? Thanks!

elm · Accepted Answer · 2015-06-03 05:16:34Z

0

In Scala (following tag in question), define this regex

val re = "USER ID:\\s+\\d+".r

where we allow for several spaces before the sequence of digits; thus for

val a = "Today USER ID: 123556 cancelled"

re.findFirstIn(a)
Option[String] = Some(USER ID: 123556)

delivers Some[String] value if the pattern was found, None otherwise.

To respond whether the pattern was found, consider

re.findFirstIn(a).isDefined
res: Boolean: true

answered Jun 3, 2015 at 5:16

elm

20.5k15 gold badges72 silver badges116 bronze badges

Collectives™ on Stack Overflow

Using regular expression (String + number) in Scala

3 Answers 3

2 Comments

3 Comments

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

3 Answers 3

2 Comments

3 Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Related