Detailed application areas of scala language

Introduction to Scala

Scala is a multi-paradigm programming language, a Java-like programming language designed to implement scalable languages ​​and integrate features of object-oriented programming and functional programming.

Scala is a pure object-oriented language. Although java is an object-oriented language, it is not pure, because the basic data types of java are not classes, and there are static member variables and static methods in java. In contrast, scala is purely object-oriented, each value is an object, and each operation is a method call.

Detailed application areas of scala language

Features of Scala 1. Object-oriented features

Scala is a pure object-oriented language, and every value is an object. The data type and behavior of an object are described by classes and features (Trait). There are two ways to extend the class abstraction mechanism. One approach is subclass inheritance, and the other is a flexible Mixin mechanism. These two approaches can avoid the problems of multiple inheritance.

2. Functional programming

Scala is also a functional language whose functions can also be used as values. Scala provides a lightweight syntax for defining anonymous functions, supporting higher-order functions, allowing nested multi-layer functions, and supporting currying. Scala's CaseClass and its built-in pattern matching are equivalent to the algebraic type commonly used in functional programming languages ​​(AlgebraicType).

Further, programmers can use Scala's pattern matching to write code similar to regular expressions to process XML data. In these cases, the compohension function of the sequential container is very useful for writing formulated queries.

Since the JVM does not support tail recursion, Scala does not fully support tail recursive optimization. However, in the simple case, the Scala compiler can optimize the tail recursion to a loop.

4. Static type

Scala is a type system that guarantees code security and consistency through compile-time checks. The type system specifically supports the following features:

A generic class, VarianceAnnotation, the upper and lower bounds of a type-inherited structure, with categories and abstract types as object members, composite types, explicitly specifying types, views, and polymorphic methods when referring to itself.

5. Scalability

Scala's design recognizes the fact that in practice, a domain-specific application development often requires language extensions specific to that domain. Scala provides a number of unique language mechanisms that make it easy to seamlessly add new language constructs in the form of libraries:

Any method can be used as a prefix or suffix operator to automatically construct a closure based on the expected type. Using these two features together allows you to define new statements without extending the syntax or using metaprogramming features such as macros.

5. Use Scala's framework

Lift is an open source web application framework designed to provide something like RubyonRails. Because Lift uses Scala, the Lift application can use all Java libraries and web containers.

Detailed application areas of scala language

Scala language main application areas

Cala runs on top of the JVM, and it can access any Java class library and interoperate with the Java framework. Scala also heavily reuses Java types and libraries.

The reason big data development language is Scala:

1: Big data itself is computational data, and Scala has the ability to organize project engineering for object-oriented, as well as the ability to calculate data.

2: Nowadays big data is actually the standard framework for computing Spark, which was developed with Scala. Because of the computational data, Scala is functional programming, which implements the algorithm very simple and elegant.

Example: kafka, which is a message middleware. If external data is to flow into the big data center, we generally use kafka as an adapter. If the data flow of the big data center is external, it is also calculated by kafka (such as Spark). To be handed over to HBASE or MySql, we will use kafka during the period. Many big data components are written in Scala, so if you want to be a high-level big data development expert, you must master Scala.

Flat-plate Solar Water Heater

Flat-Plate Solar Water Heater,Split Flat Plate Solar Water System,High Efficiency Flat Solar Water Heater,Flat Plate Solar Collectors

Shandong Sangle Group Co.,Ltd. , https://www.sangle-group.com