Scala Learning Review (ii)----Scala function definition, Process control, and exception handling

Note: This study originates from: DT Big Data DreamWorks (public number: Dt_spark)

1.in the previous section we learned about Scala Hello World, specifically defining a function as follows:

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2.define a function without parameters, as follows:

650) this.width=650; "src=" http://s3.51cto.com/wyfs02/M00/70/3D/wKioL1W1CozyVPGcAAHe2HM7cVE046.jpg "title=" 2.png " alt= "Wkiol1w1cozyvpgcaahe2hm7cve046.jpg"/>

Operation Result:

650) this.width=650; "src=" http://s3.51cto.com/wyfs02/M00/70/40/wKiom1W1CLqB3E5yAADWrR3mpMw688.jpg "title=" 3.png " alt= "Wkiom1w1clqb3e5yaadwrr3mpmw688.jpg"/>

3.define a function with parameters, as follows:

650) this.width=650; "src=" http://s3.51cto.com/wyfs02/M01/70/3D/wKioL1W1CryBnphpAAGYqmG_WWc417.jpg "title=" 4.png " alt= "Wkiol1w1crybnphpaagyqmg_wwc417.jpg"/>4, Process Control

650) this.width=650; "src=" http://s3.51cto.com/wyfs02/M01/70/40/wKiom1W1COrAA4HTAAHQnWcf5ss640.jpg "title=" 5.png " alt= "Wkiom1w1coraa4htaahqnwcf5ss640.jpg"/> If the parameter is entered when running, the situation is as follows:

650) this.width=650; "src=" http://s3.51cto.com/wyfs02/M00/70/3D/wKioL1W1CwDDYLGNAAF_UKugmdk668.jpg "style=" float: none; "title=" 6-1.png "alt=" Wkiol1w1cwddylgnaaf_ukugmdk668.jpg "/>

650) this.width=650; "src=" http://s3.51cto.com/wyfs02/M02/70/3D/wKioL1W1CwXT_kJMAAKBh6HvmSk379.jpg "style=" float: none; "title=" 6-2.png "alt=" Wkiol1w1cwxt_kjmaakbh6hvmsk379.jpg "/>

Way two:

650) this.width=650; "src=" http://s3.51cto.com/wyfs02/M02/70/40/wKiom1W1CT6A6ujTAAIRFXx0Nfg892.jpg "title=" 7.png " alt= "Wkiom1w1ct6a6ujtaairfxx0nfg892.jpg"/> can also put functions directly into the output statement:

As follows:

println ( Span style= "Font-size:16px;font-family:consolas;color:rgb (204,120,50);" >if (!args.isempty) Args ( ) else Span style= "Font-size:16px;font-family:consolas;color:rgb (106,135,89);" > "Scala.txt"

5.for Loop

mode 1:

650) this.width=650; "src=" http://s3.51cto.com/wyfs02/M00/70/3D/wKioL1W1C1DyxVOUAAD8GzvPenE977.jpg "title=" 8-1. PNG "alt=" wkiol1w1c1dyxvouaad8gzvpene977.jpg "/> mode 2: (Lists all files in the current directory)

650) this.width=650; "src=" http://s3.51cto.com/wyfs02/M01/70/3D/wKioL1W1C2rzPkWfAAIYoPv3veI083.jpg "title=" 8-2. PNG "alt=" wkiol1w1c2rzpkwfaaiyopv3vei083.jpg "/>6, exception handling

Similar to Java, the exception is handled by Try,catch, but, unlikeScala, it uses a case to match a different exception, that is, in a catch can write many exceptions, as long as the first match succeeds, the following exception will not match.

650) this.width=650; "src=" http://s3.51cto.com/wyfs02/M02/70/3D/wKioL1W1C3mAzYFPAAFtkaa8B8U651.jpg "title=" 9.png " alt= "Wkiol1w1c3mazyfpaaftkaa8b8u651.jpg"/>

Resources:

DT Big Data Dream Factory public number: Dt_spark

This article is from "My Heart Flying" blog, please make sure to keep this source http://10562836.blog.51cto.com/10552836/1678570

Scala Learning Review (ii)----Scala function definition, Process control, and exception handling