How to use java built-in functional interface

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1. Predicate is a Boolean function with only one input parameter. The Predicate interface contains a variety of default methods to handle complex logical verbs.

Predicate predicate = (s)-> s.length () > 0; predicate.test ("foo"); / / truepredicate.negate () .test ("foo"); / / false Predicate nonNull = Objects::nonNull;Predicate isNull = Objects::isNull; Predicate isEmpty = String::isEmpty;Predicate isNotEmpty = isEmpty.negate ()

2. The Function interface receives a parameter and returns a single result. By default, multiple functions can be concatenated together.

Function toInteger = Integer::valueOf;Function backToString = toInteger.andThen (String::valueOf); backToString.apply ("123"); / /" 123"

3. The Supplier interface produces results of a given type. Unlike Function,Supplier, there are no input parameters.

Supplier personSupplier = Person::new;personSupplier.get (); / / new Person Thank you for reading, this is the content of "how to use java built-in functional interface". After the study of this article, I believe you have a deeper understanding of how to use java built-in functional interface, and the specific use needs to be verified in practice. Here is, the editor will push for you more related knowledge points of the article, welcome to follow!