Efficient String Splitting in Java

General Discussions
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1

How can I split string Java efficiently using a delimiter? For example, I want to split "004-034556" into two separate strings based on the "-" delimiter:

part1 = "004";
part2 = "034556";

The first string should contain the characters before "-", and the second string should contain the characters after it. Additionally, I want to check if the string contains the delimiter before performing the split.

2

The most straightforward way? Just use split(). It’s simple and gets the job done.

public class StringSplitExample {
    public static void main(String[] args) {
        String str = "004-034556";

        if (str.contains("-")) {  // Check if the delimiter exists
            String[] parts = str.split("-");
            String part1 = parts[0];
            String part2 = parts[1];

            System.out.println("Part 1: " + part1);
            System.out.println("Part 2: " + part2);
        } else {
            System.out.println("Delimiter not found.");
        }
    }
}

This method works great for basic cases, but it does create an extra array, which might not be ideal for performance-sensitive scenarios.

3

But for those who like the old-school way, there’s also StringTokenizer. It’s not as common now, but still handy in some cases, especially if you need to iterate through multiple tokens.

import java.util.StringTokenizer;

public class StringSplitExample {
    public static void main(String[] args) {
        String str = "004-034556";

        if (str.contains("-")) {  // Check if delimiter exists
            StringTokenizer tokenizer = new StringTokenizer(str, "-");
            String part1 = tokenizer.nextToken();
            String part2 = tokenizer.nextToken();

            System.out.println("Part 1: " + part1);
            System.out.println("Part 2: " + part2);
        } else {
            System.out.println("Delimiter not found.");
        }
    }
}

It’s a bit old-fashioned since StringTokenizer has been discouraged in favor of split() or Scanner, but it still works fine if you need something lightweight.