Redis is NoSQL key-value in-memory distributed data store. It can be used as super-fast database, cache or message broker. Please check out this very useful article about Redis Cluster Setup on Linux: Configuring and Running Redis Cluster on Linux
As you probably know in Java 8 we can use Lambda expression for different manipulations with collections.
If you have a List with some custom objects inside and you want to find specific element in it you can use stream().filter procedure of Lambda instead of ForEach as you probably used to. Below is a simple example of this case.