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Strings Beginner

String.indent() and transform()

Indent text and chain string transformations fluently.

Code Comparison

✕ Java 8

String[] lines = text.split("\n");
StringBuilder sb = new StringBuilder();
for (String line : lines) {
    sb.append("    ").append(line)
      .append("\n");
}
String indented = sb.toString();

✓ Java 12+

String indented = text.indent(4);

String result = text
    .transform(String::strip)
    .transform(s -> s.replace(" ", "-"));

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Why the modern way wins

📏

Built-in

Indentation is a common operation — now it's one call.

🔗

Chainable

transform() enables fluent pipelines on strings.

🧹

Clean code

No manual line splitting and StringBuilder loops.

Old Approach

Manual Indentation

Modern Approach

indent() / transform()

Since JDK

Difficulty

Beginner

JDK Support

String.indent() and transform()

Available

Widely available since JDK 12 (March 2019)

How it works

indent(n) adds n spaces to each line. transform(fn) applies any function and returns the result, enabling fluent chaining of string operations.

String.isBlank()

Java 8

boolean blank =
    str.trim().isEmpty();
// or: str.trim().length() == 0

Java 11+

boolean blank = str.isBlank();
// handles Unicode whitespace too

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JDK 11+ →

Strings Beginner

String.strip() vs trim()

Java 8

// trim() only removes ASCII whitespace
// (chars <= U+0020)
String clean = str.trim();

Java 11+

// strip() removes all Unicode whitespace
String clean = str.strip();
String left  = str.stripLeading();
String right = str.stripTrailing();

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JDK 11+ →

Strings Beginner

String.lines() for line splitting

Java 8

String text = "one\ntwo\nthree";
String[] lines = text.split("\n");
for (String line : lines) {
    System.out.println(line);
}

Java 11+

String text = "one\ntwo\nthree";
text.lines().forEach(IO::println);

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JDK 11+ →