eclipse-collections/eclipse-collections

Health v2 · maintenance only

Flags: no_license

Adoption not part of the score

2648 stars · 690 forks observed · 2026-08-28

What it is AI-extracted, prompt v1, taxonomy v1, 2026-08-30, confidence not recorded

Eclipse Collections is a comprehensive collections framework for Java offering optimized data structures like Bag and primitive collections, plus a rich, fluent, functional API inspired by Smalltalk. It is compatible with the standard Java Collection Framework and supports eager, lazy, serial, and parallel iteration.

Use cases

• replace Java streams with more expressive collection APIs
• use immutable collections in Java
• work with primitive collections without boxing
• count elements with a Bag data structure
• perform lazy and parallel iteration over collections
• write fluent functional code over lists and sets in Java

When to choose

• you want richer, more fluent collection APIs than the JDK or Streams
• you need memory-efficient primitive collections or Bags
• you want immutable collection types with a mature, well-tested library

When to avoid

• your project must avoid extra dependencies and JDK collections suffice
• you are not on the JVM or using Java
• you need collections interoperable with non-JVM languages

Facets

library · maturity stable

serialization developer-tools performance jvm collections data-structures functional-programming immutable-collections primitive-collections java algorithms

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