Getting Started with "C1" Scala

1.scala Interpreter

The installation process is similar to a JDK installation, you need to install the JDK first, and then download and install Scala to configure the PATH environment variable.

2. Run cmd in the win environment using WIN+R, bring up the command window, execute the callout command

①scala Support TAB Command Auto-completion

②scala Support Type automatic decision

C:\users\martin>scalawelcome to Scala version 2.11.4 (Java HotSpot (TM) 64-bit Server VM, Java 1.7.0_6
7).
Type in expressions to has them evaluated.
Type:help for more information.

Scala> 8*5+2res0:int = 42

scala> 0.5*res0res1:double = 21.0

Scala> "Hello," +res1res2:string = hello,21.0

scala> Res2.totochararray tolowercase toString touppercase

scala> res2.toUpperCaseres3:String = hello,21.0

Scala>

3. Declaration of variables and values

①scala supports Val, var two ways of declaring

②val similar to the final definition in Java, for immutable pointing declarations

③scala Support for batch declarations

Scala>Val answer=8*5+2Answer:int = 42scala>0.5*answerRes4:double = 21.0scala>answer = 0

<console>:8:error:reassignment to Val answer = 0 ^scala>var counter = 0Counter:int = 0scala>counter = 5Counter:int = 5

Scala> Val answer=8*5+2
Answer:int = 42

Scala>0.5*answer
Res4:double = 21.0

Scala>answer = 0
<console>:8:error:reassignment to Val
Answer = 0
^
Scala>var counter = 0
Counter:int = 0

Scala>counter = 5
Counter:int = 5

4. Common Types

①scala supports Java-like common basic types in 8, Byte, Char, short, Int, Long, Float, Double, Boolean

②scala does not deliberately distinguish between basic and reference types, all classes, and no wrapper type

5. Operators

Scala Support +-*/% & | ^ >> << ET, note: These operators are actually methods

6. Calling functions and methods

①scala Import Reference Package Imports Scala.math._//wildcard characters _, and Java similar to *

②scala has no static method, and a similar attribute is called a singleton object (Singleton objects). Usually a Scala class has a companion object (Companion objects), and its methods are similar to the Java static methods

Scala> Bigint.probableprime (100,scala.util.random)
Res5:scala.math.BigInt = 799354413129363757440390082331

7.apply method

Methods like function calls are often used in Scala.

For example, "Hello" (4) writing "Hello". Apply (4)

8.DOC Documentation

Doc online Documentation

Getting Started with "C1" Scala