RegEx in Java making my head hurt

[slim parcel]

I am trying to use the String.matches() method to check if a string is 4 character long and only contains the character "RGBY".
In Java however, it always returns false even when it looks like it should be true.
This is my regex "/[RBGY]{4}/", which works outside of Java. Any ideas? Ty

[subtle escarp]

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[subtle escarp]

Please format your code to make it more readable.
For java, it should look like this:
```​​​`​java
public void foo() {

}
​​​`​```

[surreal crown]

/ shouldn't be part of the regex

[slim parcel]

oh

:)

[surreal crown]

/ are delimiters, like "
they aren't part of the regex's content
java doesn't have regex literals, so / isn't used

make sure you're choosing the java flavor when you test your regexes

[slim parcel]

Thank you so much! I was having such a hard time, I really appreciate it

[subtle escarp]

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[surreal crown]

note the quotes here

and when copied: "a"gm
no slashes

[slim parcel]

Which tool are you using?

[surreal crown]

(the gm flags are a separate thing, they don't work like this, but they do for regex literals; this is probably a bug)

[surreal crown]

https://regex101.com

[slim parcel]

Thank you so much, @surreal crown You're a life saver