scala in depth

Since I have been using idea to develop a Java project, Scala can now also use idea development: http://www.jetbrains.com/idea/Community Edition free and Ultimate Edition free 30-day trial all support Scala development, I use the Ultimate EditionWhen we download idea after installing and booting, we need to install a Scala Plugin, the following steps:The followin

The Github:https://github.com/scala/scala-tool-support project collects the configuration that the editor supports for Scala.1. The following Scala code is to get the vim configuration under Scala-tool-support.The Code of the blog shows that there is a pit, can be viewed her

2, Scala simple example Reference Tutorial: HTTPS://YQ.ALIYUN.COM/TOPIC/69 2.1 Interactive Programming Spark-shell is spark interactive operating mode, provides interactive programming, side-knocking code side execution, do not need to create program source files, convenient debugging procedures, conducive to rapid learning spark. [Root@node1 spark-2.2.0]# Bin/spark-shell Using Spark ' s default log4j profile:org/apache/spark/ Log4j-defaults.properti

Scala is a object-oriented, statically-typed and functional programming language for the JVM. The strength of Scala lies in it's powerful syntax which allows to write readable, manageable code which are short and conc Ise–and It comes with great support for common design pattern (i.e. a special keyword for implementing the Singleton des IGN pattern). There is plenty of good tutorials and introductions for l

Why do you write this blog?First of all, for the Spark project, it is highly recommended to build, with IntelliJ idea (Ultimate version), if you have another hobby to try Scala ideas for Eclipse, have time to play for yourself. But it's best to follow the crowd.For Hadoop projects, Eclipse is strongly recommended.Second, out of a Bo friends to give me the need to leave a message, in order to more efficient and high-quality help everyone, comb write do

Learn Scala together with Lian le-advanced type, scala-type Welcome to join Scala discussion QQ Group 212859367, and join! Singleton type Example: class Document{ def setTitile(title: String) = {...; this} def setAuthor(author: String) = {...; this} ...}val atticle.setTitle("whatever floats your boat").setAuthor("lianle") If the above classes have child

Scala learning notes, scala Learning The notes are complex! 1. The Singleton objects in Scala are decorated with objects, similar to static classes in C ++. When calling its internal functions, you can call them directly using the object name. You cannot apply for a new function! 2. A file can define classes and Singleton objects with the same name. A singleton O

In Java, variable types fall into two main categories: primitive types and reference types. Although the auto-boxing and auto-unpacking mechanisms have been introduced after JDK1.5, we have greatly reduced our entanglement between the direct and reference types, but there are still some issues that we have to consider. For example, I encountered a problem with the base type and the default value of its wrapper type, such as generics can only use reference types, such as by default the value of t

Scala Beginner's intermediate-Advanced Classic (66th: Scala concurrent programming experience and its application in Spark source code) content introduction and video link2015-07-24DT Big Data Dream FactoryFrom tomorrow onwards, be a diligent person.Watch videos, videos, share videosDT Big Data Dream Factory-scala--Advanced Classic: 66th: The first experience of

Scala is famous recently, but it is really so good. What I see is nothing. Scala's fame masks its shortcomings, so many people do not see its shortcomings. Although it is a functional programming language, it gives me the overall feeling of confusion and inconsistency, to be different, do you have to be different from other languages to show your excellence? You know, Java has been tested for more than 20 years. Isn't it worth learning from? Are you s

We talked about getting started with Scala, but after all, it's not like scripting language, and Scala is talking about replacing Java, so we'll see how he grabs the Java position.A common editor for Scala, see below: Eclipse (using one of the shoddy and unstable Scala plugins) Emacs IntelliJ (basicall

The main contents of this article are as follows: Variables and invariants Functions and procedures Parameters of the function Semicolon 1. Variables and invariants 1.1. VariablesScala's variables are divided into two types, Var and val. var, or variable, is similar to the variables we touch in other languages such as Java, and Val, is value, similar to the non-assignable constants we use in other languages, or the final variable.Why this difference, this is because in

Scala briefly -- class and object, scalaClass In scala, classes are not declared as public. The source file can contain multiple classes, all of which have common visibility. The getter and setter methods are provided for each field, which are called Field Names and field name_, respectively, and can be customized. Note: 1) if the field is private, getter and setter are also private. 2) if the field is val

"Editor's note" Although Java has won a lot of developers love, but compared to other modern programming languages, its syntax is indeed slightly lengthy. But with Java8, you can write code that is both readable and concise by using lambda expressions directly. The author Hussachai Puripunpinyo's software engineer, who analyzed the differences in performance and expression by comparing Java 8 and Scala, and discussed in

Scala: Operator and parser, scala operator ParsingThe names of variables, functions, and classes are collectively referred to as identifiers. The backquotes can contain almost any character sequence.In scala,-Operator ending with Colon-Value assignment operatorAll operators are left-bound. The unapply method accepts an object and then takes the value from it, us

The trait definition in Scala includes a collection of fields, behaviors (methods/functions/actions), and some non-implemented functional interfaces that can be easily extended or mixed into existing classes or abstract classes.Scala's trait (trait) is a very useful feature that can be better abstracted in the design. The program is more extensible by making programs more focused on their features and better splitting the program into multiple trait m

Question: Convert the text string "[1, 2, 3, 4, 5]" to an array. Answer:val x = "[1, 2, 3, 4, 5]"Val y =x Slice (1, x.length-1) replace (",", "") Split ("")var y1= x Slice (1, x.length-1) replace (",", "") Split ("") Map (_.toint)Y1:array[int] = Array (1, 2, 3, 4, 5)or writevar y1= x.slice (1, x.length-1). Replace (",", ""). Split (""). Map (_.toint)OrVal y:array[int]= x Slice (1, x.length-1) replace (",", "") Split ("") Map (_.toint)Scala encourages

001-scala development environment Construction and HelloWorld parsingScala functional programming and object-oriented language functional programming excel at numerical computing object-oriented organization of large-scale engineering and project and team collaboration Scala will be the next great language? Spark is written in the Scala language, and Hadoop is wr

Scala: annotation and scala AnnotationAnnotations can be used to add information to various entries of a program. They are inserted into the code so that tools can process tags for them. You can use java annotations for scala classes or scala-specific annotations.In scala, a

Java programmers, why do you need to pay attention to Scala, Java programmers, and Scala? Let's take a look at Martin Odersky's design goals for Scala. What aspects should be taken into account in the process of creating a language that surpasses Java? Concession Frank Sommers: You mentioned earlier that you want to create a language that exists in the Java