Java String split() Method (original) (raw)

The split() method in Java is used to divide a string into multiple parts based on a specified delimiter (regular expression). It returns an array of substrings after splitting the original string. This method is commonly used for parsing data like CSV values, sentences, or formatted input.

Uses regular expressions (regex) as the delimiter
Returns an array of strings after splitting
The limit parameter controls the number of splits and resulting array size

**Syntax:

String[] result = string.split(String regex);
Or
String[] result = string.split(String regex, int limit);

**Parameters:

**regex: Regular expression used as the delimiter.
**limit: Controls the number of resulting substrings. Java `

public class Geeks { public static void main(String[] args) {

    String s = "Geeks for Geeks";
    String[] arr = s.split(" ");
    for (String str : arr) {
        System.out.println(str);
    }
}

}

**Explanation: In this example, a string "Geeks for Geeks" is created and split using the split(" ") method, where a space is used as the delimiter. This divides the string into individual words and stores them in an array arr. A for-each loop then iterates over the array and prints each word on a new line.

Understanding limit in split(regex, limit)

Limit Value	Behavior
limit > 0	Splits at most limit - 1 times
limit = 0	Splits fully, removes trailing empty strings
limit < 0	Splits fully, keeps trailing empty strings

Split Using Multiple Delimiters (Regex)

This code depicts how a string can be split using spaces, commas, and dots together.

Java `

public class Geeks { public static void main(String[] args) {

    String s = "This is,comma.fullstop whitespace";
    String regex = "[,\\s\\.]";
    String[] arr = s.split(regex);
    
    for (String str : arr) {
        System.out.println(str);
    }
}

}

Output

This is comma fullstop whitespace

**Explanation: **regex = "[,\\s\\.]" matches commas, spaces, and dots. The string is split wherever any of these characters appear.

Split(regex, limit) with Small Limit

The program explains how a positive limit restricts the number of splits.

Java `

public class Geeks { public static void main(String args[]) {

    String s = "geeks@for@geeks";
    String[] arr = s.split("@", 2);

    for (String a : arr)
        System.out.println(a);
}

}

**Explanation: The string is split only once (limit - 1) and the remaining content is stored in the last element.

Split(regex, limit) with Negative Limit

The code depicts how a negative limit allows unlimited splitting.

Java `

public class Geeks { public static void main(String args[]) {

    String s = "geeks@for@geeks";
    String[] arr = s.split("@", -2);

    for (String a : arr)
        System.out.println(a);
}

}

**Explanation: Negative limit performs all possible splits. No elements gets discarded.

Split by a Specific Word

Following example splits a string using a substring instead of a character.

Java `

public class Geeks { public static void main(String args[]) {

    String s = "GeeksforGeeksforStudents";
    String[] arr = s.split("for");

    for (String a : arr)
        System.out.println(a);
}

}

Output

Geeks Geeks Students

**Explanation: The delimiter "for" appears twice. Each occurrence causes a split.

Split Using Dot (.)

The example highlights why special regex characters must be escaped.

Java `

public class Geeks { public static void main(String args[]) {

    String s = "Geeks.for.Geeks";
    String[] arr = s.split("[.]");

    for (String a : arr)
        System.out.println(a);
}

}

**Explanation: . is a regex wildcard and must be escaped. [.] ensures splitting only on literal dots.

Split Using Complex Regular Expression

Java `

public class Geeks { public static void main(String args[]) {

    String s = "w1, w2@w3?w4.w5";
    String[] arr = s.split("[, ?.@]+");

    for (String a : arr)
        System.out.println(a);
}

}

**Explanation: The regex splits the string at any listed symbol. + ensures consecutive delimiters are treated as one.

Delimiter Not Present in String

Java `

public class Geeks { public static void main(String args[]) {

    String s = "GeeksforGeeks";
    String[] arr = s.split("#");

    for (String a : arr)
        System.out.println(a);
}

}

**Explanation: Since "#" is not found, the original string remains unchanged. The array contains only one element.