What is the proper way of inserting a pipe into a Java Pattern expression?

Question

What is the proper way of inserting a pipe into a Java Pattern expression?

I actually want to use a pipe as a delimiter and not the or operator.

I.E:

Answer 1

Escape it with \\:

"hello|world".split("\\|");

Answer 2

"hello|world".split("\\\\|"); --> {"hello", "world"}

First set of "\\" only yields the \ as the delimiter. Therefore 2 sets are needed to escape the pipe.

Answer 3

in Java 1.5+:

"hello|world".split(Pattern.quote("|"));

Answer 4

I have this problem a lot (encoding a regex into a Java String), so I have bookmarked the regex tool at fileformat.info; it has a nifty function where it will show you the Java String representation of a regex after you test it.