如何逃脱Java正则表达式 算子

Question

I want to ask something about java regex and hope I will find some help here.

I have a string which looks like "textX|textY|textZ" . Now I want to split this on each | character in java.

I tried it with

string.split("\|");

but I just get a "Invalid escape sequence" error.

How can I split the above string when I use | as separator?

Answer 1

You need double escaping in Java so use:

String[] tokens = string.split("\\|")

OR else use character class:

String[] tokens = string.split("[|]");

Answer 2

you should use \\\\| for escaping meta character.

Answer 3

In Java you need to escape characters twice for regex: once for the string, once for the regex.

Try

string.split("\\|")

Answer 4

You have to use double back slash \\\\ : string.split("\\\\|") .

It is because back slash is a escape character for both: java and regex. First one escapses the second for java, so that the "real" backslash is passed to regex.

Answer 5

simply doing

string.split("\\|");

in java when we escape we do it by two backslashes