Compare the comparison of the functional framework in the Java class library and the traditional programming method

The functional framework in the Java class library has received widespread attention and application in recent years.The traditional programming method focuses on the instruction programming style, while the functional framework emphasizes the use of functions as basic construct blocks to build programs.This article will compare the differences between functional frameworks in the Java library and traditional programming methods, and give examples to explain its advantages in practical applications. 1. Differences of programming paradigms 1. Command programming: The traditional programming method adopts command programming paradigm, which is characterized by a series of instructions to change the program status.This programming style usually needs to define and maintain a large number of categories and methods, and it is also easy to produce side effects, increasing the complexity and maintenance difficulty of the program. 2. Functional programming: Functional programming uses pure functions as a basic construction block of programming, emphasizing that data cannot be changed and no side effects.The function accepts the input parameter, processes it, and then returns a result. It does not modify the input parameter and does not affect the external state.This programming style has a higher level of abstraction, the code is simpler, more readable, and easier to understand and maintain. Second, the advantages of functional framework 1. Simple code: Using functional frameworks, complex functions can be achieved through simple syntax, reducing the writing of model code, making the code easier to understand and maintain.For example, using Lambda expression and Stream API introduced in Java 8 can simplify the operation of the collection. Example code: List<Integer> numbers = Arrays.asList(1, 2, 3, 4, 5); List<Integer> doubledNumbers = numbers.stream() .map(n -> n * 2) .collect(Collectors.toList()); 2. Parallel calculation: The functional framework improves the performance of the program by splitting the calculation task into multiple sub -tasks and performing these sub -tasks in parallel to perform these sub -tasks.The Stream API in Java 8 uses the concept of parallel flow, which can easily implement parallel computing. Example code: List<Integer> numbers = Arrays.asList(1, 2, 3, 4, 5); int sum = numbers.parallelStream() .mapToInt(Integer::intValue) .sum(); 3. Asynchronous programming: The function framework supports the processing task asynchronous to improve the response of the program.The CompletableFuture class in Java 8 can easily achieve asynchronous programming. Example code: CompletableFuture<String> future = CompletableFuture.supplyAsync(() -> { try { Thread.sleep(1000); } catch (InterruptedException e) { e.printStackTrace(); } return "Hello, world!"; }); future.thenAccept(System.out::println); 3. Summary Compared with the traditional programming method, the functional framework in the Java class library has the advantages of simple code, parallel computing and asynchronous programming.Functional programming styles can improve the readability, maintainability and performance of the program, and get widespread application in the process of processing collection, parallel computing and asynchronous programming.Therefore, for the need to develop efficient, flexible and scalable procedures, the functional framework is a programming paradigm worth considering.