Android Split string

Handling special cases & edge scenarios

In cases where you expect a fixed number of substrings post splitting, consider imposing a limit:

// You, me and Dupree - Threesome movie, remember?
String[] parts = "You,me,Dupree,FourthWheel".split(",", 3);
// parts = {"You", "me", "Dupree,FourthWheel"}
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When handling empty string tokens, Androids TextUtils.split()` comes handy and is highly efficient:

// Everyone: ::Jumps:: in the pool
String[] parts = TextUtils.split("Everyone:::Jumps::In the pool", ":");
// parts = {"Everyone", "Jumps", "In the pool"} // Excuse me, empty strings not allowed in the pool
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Trimming spaces post splitting

Splitting can often leave white spaces at the beginning or end of your substrings. Trim these for cleaner results:

// You know they say "    space     " is everything, right?
String[] parts = " space , space , and more space ".split(",");
for (int i = 0; i < parts.length; i++) {
    parts[i] = parts[i].trim();
}
// parts = {"space", "space", "and more space"} // The space is now truly infinite
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StringTokenizer as an alternate approach

As an alternative to split(), consider using StringTokenizer:

StringTokenizer tokenizer = new StringTokenizer("Coffee,Tea,Me", ",");
while (tokenizer.hasMoreTokens()) {
    String token = tokenizer.nextToken().trim();
    // Do something with your brewed token
}
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Note that StringTokenizer does not return empty strings, which could be a requirement in some cases.

Safe splitting and iterating over tokens

Perform checks before accessing tokens or array elements to avoid index out of bounds exceptions:

String testString = "Luke,Vader,Leia";
String[] parts = testString.split(",");
if (parts.length > 2) {
    String Luke = parts[0];
    String Vader = parts[1];  
    String Leia = parts[2];
    // Plan your next Star Wars party!
}
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When using StringTokenizer, be mindful of the NoSuchElementException:

StringTokenizer tokenizer = new StringTokenizer(testString, ",");
while (tokenizer.hasMoreTokens()) {
    try {
        String token = tokenizer.nextToken();
        // Do what needs to be done with the token
    } catch (NoSuchElementException e) {
        // When you run out of tokens, become the token!
    }
}
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Displaying split tokens in Android Views

Once split, you might want to display each substring in TextViews:

TextView tvOne = findViewById(R.id.tv_one);
TextView tvTwo = findViewById(R.id.tv_two);
TextView tvThree = findViewById(R.id.tv_three);

String[] parts = "Love:Peace:Joy".split(":");
tvOne.setText(parts.length > 0 ? parts[0] : "");
tvTwo.setText(parts.length > 1 ? parts[1] : "");
tvThree.setText(parts.length > 2 ? parts[2] : "");
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Real-world scenarios

Imagine having to handle CSV files, or response tokens from APIs! A robust parsing method is essential, considering quirks such as escaped characters or quoted sections.

String complexString = "It<splitsville>for<us>";
String[] parts = complexString.split("<splitsville>");
// parts = {"It", "for<us>"}
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Don't forget to escape special regex characters (*, +, ?, etc.) using \\ when using them as delimiters.

Split with caution - sanitize input and handle errors

Sanitize inputs and employ thorough error handling.

String userInput = "Cat - Dog - Squirrel  "; 
String[] pets = userInput.split(" - ");
// Pets = {"Cat", "Dog", "Squirrel"} // Clean as a whistle!
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Think of dynamic scenarios, such as delimiters or input strings that may change at runtime and affect the split logic.

Best practices for parsing and splitting

1. Encapsulate your parsing logic in specific functions
2. Use regular expressions with caution due to their potential performance implications
3. Validate input strings and delimiters to mitigate the risk of runtime errors
4. Always ponder on the variety of input your split method can handle

With thoughtful design, your splitting logic will be resilient and future-proof against an array of use cases and data inputs.