Learn Java 8 streams by example: functional programming with filter, map, flatMap, reduce, collect, lambdas, sequential and parallel streams are covered in-depth in this tutorial.
Eclipse is an open-source community project that is focused on building an extensible development platform: a suite of software tools that assist in the writing of software. Primarily it is used as a Java integrated development environment (IDE) but has been adapted for many other languages including python, C, C++, and FORTRAN.