use modern Java syntax

Prefer modern Java language features and constructs to write more concise, readable code. Since Apache Spark 4.0.0, the project recommends using contemporary Java syntax where applicable.

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Prefer modern Java language features and constructs to write more concise, readable code. Since Apache Spark 4.0.0, the project recommends using contemporary Java syntax where applicable.

Key practices:

  • Use switch expressions (JEP-361) instead of traditional switch statements for cleaner, more compact code
  • Use Java records for simple data structures instead of classes with boilerplate code
  • Leverage pattern matching and other modern language features when appropriate

Examples:

Switch expressions - Replace verbose switch statements:

// Instead of:
BloomFilter result;
switch (version) {
  case 1:
    result = BloomFilterImpl.readFrom(bin);
    break;
  case 2:
    result = BloomFilterImplV2.readFrom(bin);
    break;
  default:
    throw new IllegalArgumentException("Unknown BloomFilter version: " + version);
}
return result;

// Use:
return switch (version) {
  case 1 -> BloomFilterImpl.readFrom(bin);
  case 2 -> BloomFilterImplV2.readFrom(bin);
  default -> throw new IllegalArgumentException("Unknown BloomFilter version: " + version);
};

Records for data structures - Use records instead of classes for simple data holders:

// Instead of a class with boilerplate:
public final class JoinColumn implements NamedReference {
  // constructor, getters, equals, hashCode, toString...
}

// Use a record:
public record JoinColumn(...) implements NamedReference {
  // automatic constructor, getters, equals, hashCode, toString
}

This approach reduces boilerplate code, improves readability, and takes advantage of language improvements that make code more maintainable.

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