Splitting a string into a list in Java

Question

I'm trying to split a string into a list base on :,"{[ }] This is my code,

List<String> list = new ArrayList<String>(Arrays.asList(line.split("{ | } | \\"| : | [ | ]|,")));

Which isn't compiling. I'm not really adept at regex. Any help please.

Possible duplicate of [How to convert a String into an ArrayList?](http://stackoverflow.com/questions/7347856/how-to-convert-a-string-into-an-arraylist) — lmiguelvargasf, Apr 11 '17 at 23:22
@lmiguelvargasf I can convert the string if the delimiter is just 1 comma, but not in this case, thus the question. — Melissa Stewart, Apr 11 '17 at 23:22
@CasimiretHippolyte kind of yes and no, it was json which I've transformed into a Java string now. — Melissa Stewart, Apr 11 '17 at 23:25
@Jérôme that's a little difficult as it has enterprise data in it. But I've worded the question correctly. — Melissa Stewart, Apr 11 '17 at 23:29
Are you going to split string by either of `:,"{[ }]`? Please provide the input and expected output:-) — shizhz, Apr 11 '17 at 23:30
Take a look here: http://stackoverflow.com/questions/2591098/how-to-parse-json-in-java — Casimir et Hippolyte, Apr 11 '17 at 23:41

Mike 'Pomax' Kamermans · Accepted Answer · 2017-04-11T23:45:40.343

Do you mean you want it split "whenever you see : or , or " or { or [ or } or ]"? If so, you really don't need to say much more than:

.split("[:,\"{\\[ }\\]]")

I.e. "split on any character in the following character class definition: :,"{[ }]", where we use the standard regexp character class definition syntax ([...]) with appropriate escaping.

Normally this means a regex that looks like /[:,"{\[ }\]]/ but because you're writing a regex inside of a normal string, more escapes are needed: " needs regular string escaping so your string doesn't end prematurely (so that becomes \"), and [ and ] are active characters in the regexp, so they need \ before them in the regex. However, we can't just put \ in the string and have it work because \ is the escape character, so we need to "escape the escape" which means using \\ (giving \\[ and \\]).

String[] result = "a:b,c\"d{e[f g}h]i".split("[:,\"{\\[ }\\]]");
System.out.print(result.length);
// => result has 9 elements in it, ['a',...,'i']

score 1 · Answer 2 · answered Apr 11 '17 at 23:32

1

It's not compiling because you didn't escape the quotation mark, but the backslash itself.

Change:

\\"

To:

\"

answered Apr 11 '17 at 23:32

Jacob G.

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Splitting a string into a list in Java

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