working with streams

Streams provide a declarative way to process collections of data in Java. Instead of writing loops and managing mutable state, streams allow us to describe what we want to do with data—such as filtering, transforming, or aggregating—while the Stream API takes care of iteration and execution. Core stream operations like filtering, mapping, flatMap, and reduce form the backbone of most real-world stream pipelines. Filtering helps narrow down data based on conditions, mapping transforms elements into new forms, flatMap handles one-to-many transformations and nested structures, and reduce enables aggregation into a single result. The articles under this section explain these operations step by step, with practical examples, helping you understand how to build readable, efficient, and maintainable stream pipelines in everyday Java applications.