How to split a String by space

What you have should work. If, however, the spaces provided are defaulting to... something else? You can use the whitespace regex:

str = "Hello I'm your String";String[] splited = str.split("\\s+");

This will cause any number of consecutive spaces to split your string into tokens.

As a side note, I'm not sure "splited" is a word :) I believe the state of being the victim of a split is also "split". It's one of those tricky grammar things :-) Not trying to be picky, just figured I'd pass it on!

While the accepted answer is good, be aware that you will end up with a leading empty string if your input string starts with a white space. For example, with:

String str = " Hello I'm your String";String[] splitStr = str.split("\\s+");

The result will be:

splitStr[0] == "";splitStr[1] == "Hello";splitStr[2] == "I'm";splitStr[3] == "Your";splitStr[4] == "String";

So you might want to trim your string before splitting it:

String str = " Hello I'm your String";String[] splitStr = str.trim().split("\\s+");

[edit]

In addition to the trim caveat, you might want to consider the unicode non-breaking space character (U+00A0). This character prints just like a regular space in string, and often lurks in copy-pasted text from rich text editors or web pages. They are not handled by .trim() which tests for characters to remove using c <= ' '; \s will not catch them either.

Instead, you can use \p{Blank} but you need to enable unicode character support as well which the regular split won't do. For example, this will work: Pattern.compile("\\p{Blank}", UNICODE_CHARACTER_CLASS).split(words) but it won't do the trim part.

The following demonstrates the problem and provides a solution. It is far from optimal to rely on regex for this, but now that Java has 8bit / 16bit byte representation, an efficient solution for this becomes quite long.

public class SplitStringTest{    static final Pattern TRIM_UNICODE_PATTERN = Pattern.compile("^\\p{Blank}*(.*)\\p{Blank}$", UNICODE_CHARACTER_CLASS);    static final Pattern SPLIT_SPACE_UNICODE_PATTERN = Pattern.compile("\\p{Blank}", UNICODE_CHARACTER_CLASS);    public static String[] trimSplitUnicodeBySpace(String str)    {        Matcher trimMatcher = TRIM_UNICODE_PATTERN.matcher(str);        boolean ignore = trimMatcher.matches(); // always true but must be called since it does the actual matching/grouping        return SPLIT_SPACE_UNICODE_PATTERN.split(trimMatcher.group(1));    }    @Test    void test()    {        String words = " Hello I'm\u00A0your String\u00A0";        // non-breaking space here --^ and there -----^        String[] split = words.split(" ");        String[] trimAndSplit = words.trim().split(" ");        String[] splitUnicode = SPLIT_SPACE_UNICODE_PATTERN.split(words);        String[] trimAndSplitUnicode = trimSplitUnicodeBySpace(words);        System.out.println("words: [" + words + "]");        System.out.println("split: [" + Arrays.stream(split).collect(Collectors.joining("][")) + "]");        System.out.println("trimAndSplit: [" + Arrays.stream(trimAndSplit).collect(Collectors.joining("][")) + "]");        System.out.println("splitUnicode: [" + Arrays.stream(splitUnicode).collect(Collectors.joining("][")) + "]");        System.out.println("trimAndSplitUnicode: [" + Arrays.stream(trimAndSplitUnicode).collect(Collectors.joining("][")) + "]");    }}

Results in:

words: [ Hello I'm your String ]split: [][Hello][I'm your][String ]trimAndSplit: [Hello][I'm your][String ]splitUnicode: [][Hello][I'm][your][String]trimAndSplitUnicode: [Hello][I'm][your][String]

I do believe that putting a regular expression in the str.split parentheses should solve the issue. The Java String.split() method is based upon regular expressions so what you need is:

str = "Hello I'm your String";String[] splitStr = str.split("\\s+");