Java string split() Regex

Question

I have a string like this,

["[number][name]statement_1.","[number][name]statement_1."]

i want to get only statement_1 and statement_2 . I used tried in this way,

String[] statement = message.trim().split("\\s*,\\s*");

but it gives ["[number][name]statement_1." and "[number][name]statement_2."] . how can i get only statement_1 and statement_2 ?

Answer 1

Match All instead of Splitting

Splitting and Match All are two sides of the same coin. In this case, Match All is easier.

You can use this regex:

(?<=\])[^\[\]"]+(?=\.)

See the matches in the regex demo .

In Java code:

Pattern regex = Pattern.compile("(?<=\\])[^\\[\\]\"]+(?=\\.)");
Matcher regexMatcher = regex.matcher(yourString);
while (regexMatcher.find()) {
    // the match: regexMatcher.group()
} 

In answer to your question to get both matches separately:

Pattern regex = Pattern.compile("(?<=\\])[^\\[\\]\"]+(?=\\.)");
Matcher regexMatcher = regex.matcher(yourString);
if (regexMatcher.find()) {
    String theFirstMatch: regexMatcher.group()
} 
if (regexMatcher.find()) {
    String theSecondMatch: regexMatcher.group()
} 

Explanation

• The lookbehind (?<=\\]) asserts that what precedes the current position is a ]
• [^\\[\\]"]+ matches one or more chars that are not [ , ] or "
• The lookahead (?=\\.) asserts that the next character is a dot

Reference

• Match All and Split are Two Sides of the Same Coin
• Lookahead and Lookbehind Zero-Length Assertions
• Mastering Lookahead and Lookbehind

Answer 2

I somehow don't think that is your actual string, but you may try the following.

String s = "[\"[number][name]statement_1.\",\"[number][name]statement_2.\"]";
String[] parts = s.replaceAll("\\[.*?\\]", "").split("\\W+");
System.out.println(parts[0]); //=> "statement_1"
System.out.println(parts[1]); //=> "statement_2"

Answer 3

is the string going to be for example [50][James]Loves cake?

    Scanner scan = new Scanner(System.in);

    System.out.println ("Enter string");

    String s = scan.nextLine();

    int last = s.lastIndexOf("]")+1;

    String x  = s.substring(last, s.length());

    System.out.println (x);


Enter string
[21][joe]loves cake
loves cake

Process completed.

Answer 4

Use a regex instead.

With Java 7

    final Pattern pattern = Pattern.compile("(^.*\\])(.+)?");

    final String[] strings = { "[number][name]statement_1.", "[number][name]statement_2." };

    final List<String> results = new ArrayList<String>();

    for (final String string : strings) {
        final Matcher matcher = pattern.matcher(string);
        if (matcher.matches()) {
            results.add(matcher.group(2));
        }
    }

    System.out.println(results);

With Java 8

    final Pattern pattern = Pattern.compile("(^.*\\])(.+)?");

    final String[] strings = { "[number][name]statement_1.", "[number][name]statement_2." };

    final List<String> results = Arrays.stream(strings)
            .map(pattern::matcher)
            .filter(Matcher::matches)
            .map(matcher -> matcher.group(2))
            .collect(Collectors.toList());

    System.out.println(results);