Difficulty splitting string at delimiter and keeping it

Question

I have a string that is read in pairs, separated by comma. However, I do not always want to split at the comma because there is not always 1 comma in the input. For example, the string,

(http://www.wolframalpha.com/input/?i=103%2F30+%3D+4a-3b,+71%2F60+%3D+a+%2B+b
,http://www.wolframalpha.com/input/?i=x%5E2%2B5x%2B6,file:///tmp/foo/bar/p,d,f.pdf)

Is read in all one line. For this case, I only want to split at the ,h, and no where else in the string. Essentially, after the split, the strings should be:

http://www.wolframalpha.com/input/?i=103%2F30+%3D+4a-3b,+71%2F60+%3D+a+%2B+b

http://www.wolframalpha.com/input/?i=x%5E2%2B5x%2B6

file:///tmp/foo/bar/p,d,f.pdf

Maintaining the order of the comma in the first string. (I will get rid of parenthesis). I have looked at this stack overflow question, and while helpful, does not correctly split this string. This is in Java. Any help is appreciated.

score 5 · Accepted Answer · answered Dec 13 '16 at 19:44

5

You can use regex to do the split. Please see below code snippet.

String str = "(http://www.wolframalpha.com/input/?i=103%2F30+%3D+4a-3b,+71%2F60+%3D+a+%2B+b,http://www.wolframalpha.com/input/?i=x%5E2%2B5x%2B6)";
String[] strArr = str.split("(,(?=http))");

You will have Array of all the value which would be possible according to your requirement.

answered Dec 13 '16 at 19:44

SachinSarawgi

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@Nick Thank you :)). – SachinSarawgi Dec 13 '16 at 19:47
@SachinSarawgi maybe mark it as correct answer then? :-) – rob Dec 13 '16 at 19:49
@rob its depend on the user to mark it as correct answer. – SachinSarawgi Dec 13 '16 at 19:50
@rob I have to wait! Sachin answered too quickly ;) – Nick Dec 13 '16 at 19:51

Freiheit · Answer 2 · 2016-12-13T19:43:08.390

1

Split on 'http' then re-add it.

Psuedo-code

String input = "http://www.wolframalpha.com/input/?i=103%2F30+%3D+4a-3b,+71%2F60+%3D+a+%2B+b
,http://www.wolframalpha.com/input/?i=x%5E2%2B5x%2B6"

List<String> split = input.split('http');
List<String> finalList = new ArrayList<String>();

for(String fixup in split)
{
  finalList.put( "http" + fixup );
}

Final should contain the two URLs.

edited Dec 13 '16 at 19:43

answered Dec 13 '16 at 19:40

Freiheit

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6
59
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You might also have to trim off trailing commas – Freiheit Dec 13 '16 at 19:40
What if the 'http:' (the protocol part) is missing from the url? – Yoram Dec 13 '16 at 19:42
1

@Yoram - If the http part is missing then its not a URL. Based on the example given, I am assuming that this is a comma separated list of URLs which may include commas in the URL. If it is a comma separated list of something else which may include commas then a different solution will be needed. – Freiheit Dec 13 '16 at 19:43
1

@Freiheit there are some edge cases where the user opens up a PDF in the browser, so the string would be file:\\\. . . – Nick Dec 13 '16 at 19:46

Difficulty splitting string at delimiter and keeping it

2 Answers2