lambdaj

manipulate collections in a pseudo-functional and statically typed way

lambdaj is a library that makes easier to address this issue by allowing to manipulate collections in a pseudo-functional and statically typed way. In our experience to iterate over collection, especially in nested loops, is often error prone and makes the code less readable. The purpose of this library is to alleviate these problems employing some functional programming techniques but without losing the static typing of java. It constraint to make refactoring easier and safer and allow the compiler to do its job.

Access collections without explicit loops

The main purpose of lambdaj is to partially eliminate the burden to write (often nested and poorly readable) loops while iterating over collections. In particular it allows to iterate collections in order to:

• filter its items on a given condition
• convert each item with a given rule
• extract a given property from each item
• sort the items on the values of one of their property
• group or index the items on the value of one or more properties
• invoke a method on each item
• sum (or more generally aggregate) the items or the values of one of their property
• concatenate the string representation of the items or of the values of one of their property

without to write a single explicit loop.