Performance-oriented data structures for Kotlin

A collection of performance-oriented data structures providing performance and efficiency that might appear to be impossible at first glance.

If you find this library useful, please consider giving it a on GitHub and sharing it with others.

Installation

available on Maven Central:

Gradle:

repositories {
    mavenCentral()
}
dependencies {
    implementation("com.danrusu.pods4k:pods4k:<latest_version>")
}

Maven:

<dependency>
    <groupId>com.danrusu.pods4k</groupId>
    <artifactId>pods4k</artifactId>
    <version>latest_version</version>
</dependency>

Alternatively, you can pick & choose individual components of this library.

Immutable Arrays

Immutable Arrays offer a safer, faster, and more efficient alternative to lists while maintaining familiar syntax.

Key Benefits

• 2 to 8 times faster than lists for most operations.
• Over 4X memory reduction in many common scenarios.
• Cannot be modified, even with casting.
• Prevents accidental mutation attempts at compile time.
• Gather elements more efficiently than mutable lists.

Intuitive list-like syntax

val people = immutableArrayOf(dan, jill, bobby)

// Iterate naturally
for (person in people) {
    sendMarketingEmailTo(person)
}
// All the usual operations
val employedPeople = people.filter { it.isEmployed() }
val salaries = employedPeople.map { it.salary }

See Immutable Arrays for more specifics along with detailed comparisons against regular arrays, read-only lists, and immutable lists.

Minimum Requirements

• Kotlin 1.9.25
  • This library is K2 compatible as it's used in other projects that use Kotlin 2.1 etc.
• JDK 11
  • Automated tests are run on JDK LTS releases 11, 17, & 21

Java Compatibility

Some data structures use techniques which are only supported by the Kotlin compiler. While they can be used in a mixed Java & Kotlin codebase to store one of these data structures in a Java-defined collection, referencing these data structures by their class name is only supported within Kotlin files.