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Split CSV String using Regex in Java

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🎉 Splitting and Handling CSV in Java - The Fun Way​

Working with CSV (Comma-Separated Values) in Java? No worries! We’ve got some cool tricks to split, store, and play around with CSV data like a pro. Let’s dive in! 🚀

1️⃣ Splitting CSV with Regular Expression​

Want to break up a CSV string into individual words? Use a regex pattern like "\\s*,\\s*" to handle those pesky spaces around commas! ✂️

String blogName = "how, to, do, in, java";
String[] tokenArray = blogName.split("\\s*,\\s*");

Assertions.assertArrayEquals(new String[]{"how", "to", "do", "in", "java"}, tokenArray);

💡 Magic Alert! This regex cleans up extra spaces so you get clean words, not messy ones. Example:

Assertions.assertArrayEquals(new String[]{"a", "b", "c"}, "a, b,c".split("\\s*,\\s*"));
Assertions.assertArrayEquals(new String[]{"a", "b", "c"}, "a,   b,    c".split("\\s*,\\s*"));

2️⃣ Convert Array to List 🗂️​

So you’ve got an array, but lists are more fun? Use Arrays.asList() to get a fixed-size, unmodifiable list.

String[] tokenArray = blogName.split("\\s*,\\s*");
List<String> tokenList = Arrays.asList(tokenArray);

💡 Want a flexible (mutable) list? Just copy it into an ArrayList!

ArrayList<String> tokenArrayList = new ArrayList<>(Arrays.asList(tokenArray));

Now you can modify it however you like! 🎨

3️⃣ Convert a List to CSV String 🎭​

Need to stitch that list back into a CSV? Java 8's String.join() makes it effortless!

List<String> list = Arrays.asList("how", "to", "do", "in", "java");
String result = String.join(",", list);    //Delimited by comma
Assertions.assertEquals("how,to,do,in,java", result);

And boom! 🎆 You’ve got your list back into a nice CSV format.

🎯 Wrapping Up​

Now you’re a CSV ninja 🥷 in Java! Whether you're splitting CSVs, converting arrays to lists, or joining them back, these tricks will make your life easier.

🚀 Happy Coding and Learning! 🎉