Finding a pattern while being surrounded by other text in java

Question

I have a regex that finds a certain pattern. This works when the text is isolated. However I want this to work while it's being surrounded by other text and somehow extract it from there. Here's the pattern that I came up with. An example would be if 9708/32/M/J/15 is the text, it would find it. But if it's awfawf9708/32/M/J/15awfafwaf it can't find it.

Pattern pattern = Pattern.compile("^\\d{4}/\\d{2}/\\w/\\w/\\d{2}$");

How do I modify this to make it work in both scenarios?

You are probably using `Matcher.matches()`, which tries to match the entire String. You can match the partial text if you use `Matcher.find()`. — BlackPearl, Jan 11 '20 at 10:27
[This](https://regex101.com/r/XocQe0/1) works for me: `\d{4}\/\d{2}\/\w\/\w\/\d{2}`. I'm no `RegEx` nor `Java` expert, but by my understanding you reversed the escaping of the forward slash. The `^` and `$` can indeed be omitted as per @Thefourthbird. — JvdV, Jan 11 '20 at 10:33
Does this answer your question? [What do ^ and $ mean in a regular expression?](https://stackoverflow.com/questions/6908725/what-do-and-mean-in-a-regular-expression) — Ryszard Czech, Jan 11 '20 at 13:27

score 0 · Accepted Answer · answered Jan 11 '20 at 13:08

0

The ^ asserts beginning of string. $ asserts end of string. Parenthesis are used to capture what's matched inside them. Both of these will work:

(\d{4}/\d{2}/\w/\w/\d{2})
^.*(\d{4}/\d{2}/\w/\w/\d{2}).*$

I'm not sure why you were escaping your backslashes. You may need to escape your forward slashes if forward slash is used as a delimiter in your program. I prefer to use ~ as delimiter as it is a rare character.

answered Jan 11 '20 at 13:08

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I get an error of Illegal escape character on android studio. Espacing the backslashes fixes the problem – HudZah Jan 11 '20 at 15:56

Finding a pattern while being surrounded by other text in java

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