File line length exceeds 100 characters

Question

I meet a problem when I compile spark version 1.3.1. When I compiled the original source codes provided by spark,it was OK. But when I added some source files into the mllib, it came up with errors,like:

message=File line length exceeds 100 characters

Based on the information at the end of compiling

[ERROR] Failed to execute goal org.scalastyle:scalastyle-maven-plugin:0.4.0:check (default) on project spark-mllib_2.10: Failed during scalastyle execution: You have 53 Scalastyle violation(s). -> [Help 1]

It should be because of the scalastyle test. I could finish my compile process by closing the validation of scalastyle.

But is there any other ways to handle this problem? I don't think just closing the validation is good enough

Example code of Errors:
good one

val implicitPrefs =  
    new BooleanParam(this, "implicitPrefs", "whether to use implicit preference", Some(false))

bad one

val implicitPrefs = new BooleanParam(this, "implicitPrefs", "whether to use implicit preference", Some(false))

An obvious solution is not to break the style rules in the first place :) — zero323, Oct 20 '15 at 03:37
Thanks zero323. I totally agree with you, and i still wonder the restriction of file line length and the number of parameters. Is it to make the code elegant? — Shifeng.Liu, Oct 20 '15 at 04:38
Line length restrictions are mostly practical. You can easily fit 100 character in a single line on a relatively small screen without using size 6 font or something similar. Not to mention it is usually easier to read shorter lines. Regarding number of parameters... It is a relatively good measure of code complexity. I would say that more than ten is a pretty good signal there is something really wrong going on. — zero323, Oct 20 '15 at 05:00

score 0 · Accepted Answer · answered Oct 20 '15 at 10:27

0

You can also read two code files side by side if their line length has been limited to 80/100.

Scala Style also imposes worthwhile rules like braces around single if-else statements.

answered Oct 20 '15 at 10:27

Dragonborn

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I got it. Thank you very much:) – Shifeng.Liu Oct 21 '15 at 01:18
which actually contradict the Scala Style Guide - http://docs.scala-lang.org/style/control-structures.html – Todor Kolev Jan 30 '17 at 13:00

score 0 · Answer 2 · answered May 23 '19 at 14:39

I believe you should have some kind of xml configuration (e.g. scalastyle.xml) to set up scala rules for your project. So you might set up maxFileLength value up to you:

        <scalastyle>
        <name>.....</name>
        <check level="warning" class="org.scalastyle.file.FileLengthChecker" enabled="true">
          <parameters>
            <parameter name="maxFileLength">1000</parameter>
          </parameters>
        </check>
        </scalastyle>

http://www.scalastyle.org/rules-dev.html#org_scalastyle_file_FileLengthChecker

File line length exceeds 100 characters

2 Answers2