Java 8 – Convert List to Map
Few Java 8 examples to show you how to convert a List of objects into a Map, and how to handle the duplicated keys.
Java 8 Streams filter examples
In this tutorial, we will show you few Java 8 examples to demonstrate the use of Streams filter(), collect(), findAny() and orElse()
Java 8 BiPredicate Examples
In Java 8, BiPredicate is a functional interface, which accepts two arguments and returns a boolean, basically this BiPredicate is same with the Predicate, instead, it takes 2 arguments for…
Java 8 Predicate Examples
In Java 8, Predicate is a functional interface, which accepts an argument and returns a boolean. Usually, it used to apply in a filter for a collection of objects.
Java 8 Consumer Examples
In Java 8, Consumer is a functional interface; it takes an argument and returns nothing. It can act as Higher Order Function, so we can accepts Consumer as an argument,…
Java 8 forEach examples
In Java 8, we can use the new forEach to loop or iterate a Map, List, Set, or Stream. Review the forEach method signature, it accepts a functional interface Consumer.…
How to delete directory in Java
If we use the NIO Files.delete to delete a non-empty directory in Java, it throws DirectoryNotEmptyException; for legacy IO File.delete to delete a non-empty directory, it returns a false. The…
How to copy directory in Java
In Java, we can use the Java 1.7 FileVisitor or Apache Commons IO FileUtils.copyDirectory to copy a directory, which includes its sub-directories and files. This article shows a few of…
How to find files with the file extension in Java
This article shows how to Java 8 Files.walk to walk a file tree and stream operation filter to find files that match a specific file extension from a folder and…
Java create and write to a file
In Java, we can use Files.write to create and write to a file. The Files.write also accepts an Iterable interface; it means this API can write a List to a…