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Strings Beginner

String.lines() for line splitting

Use String.lines() to split text into a stream of lines without regex overhead.

Strings

Code Comparison

✕ 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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Why the modern way wins

⚡

Lazy streaming

Lines are produced on demand, not all at once like split().

🔧

Universal line endings

Handles \n, \r, and \r\n automatically without regex.

🔗

Stream integration

Returns a Stream for direct use with filter, map, collect.

Old Approach

split("\\n")

Modern Approach

lines()

Since JDK

Difficulty

Beginner

JDK Support

String.lines() for line splitting

Available

Available since JDK 11 (September 2018).

How it works

String.lines() returns a Stream<String> of lines split by \n, \r, or \r\n. It is lazier and more efficient than split(), avoids regex compilation, and integrates naturally with the Stream API for further processing.

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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Strings Beginner

String.indent() and transform()

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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JDK 12+ →