Youshallnotpass

What is it?

Youshallnotpass is the static analyser for your elegant code.

How it works?

Just see, what it can find in seemingly usual code:

package com.example;

import java.util.Collection;
import java.util.StringTokenizer;

public class Words {
    public static final String DELIM = " ,.";

    private Collection<String> words;

    public Words() {
        this.words = null;
    }

    public Words(Collection<String> words) {
        this.words = words;
    }

    boolean containsIn(String text) {
        if (words == null) return false;

        StringTokenizer tokenizer = new StringTokenizer(text, DELIM);
        while (tokenizer.hasMoreTokens()) {
            String nextWord = tokenizer.nextToken();
            if (words.contains(nextWord)) return true;
        }

        return false;
    }
}

The violations of the youshallnotpass analysis:

nullfree
com.example.Words(Words.java:12) > null
com.example.Words.containsIn(Words.java:20) > null

staticfree
com.example.A.main(A.java:6) > static 
com.example.Words(Words.java:7) > static 

allfinal
com.example.A.main(A.java:6) > String[] args
com.example.A(A.java:5) > A
com.example.Words(Words.java:9) > words
com.example.Words.containsIn(Words.java:22) > StringTokenizer tokenizer = new StringTokenizer(text, DELIM)
com.example.Words.containsIn(Words.java:24) > String nextWord = tokenizer.nextToken()
com.example.Words(Words.java:15) > Collection<String> words
com.example.Words.containsIn(Words.java:19) > String text
com.example.Words(Words.java:6) > Words

allpublic
com.example.Words.containsIn(Words.java:19)

nomultiplereturn
com.example.Words.containsIn(Words.java:19)

Get started

Gradle

Add the plugin to the root build.gradle

plugins {
    id 'dev.youshallnotpass' version 'x.y.z'
}

// then configure it, if you need:
youshallnotpass {
    offline = true // default false
    nullfree {
        disabled = true // default false
        threshold = 3 // default 0
        skipComparisons = true // default false
    }
    staticfree {
        disabled = true // default false
        threshold = 2 // default 0
    }
    allfinal {
        disabled = true // default false
        threshold = 1 // default 0
        skipInterfaceMethodParams = false // default true
        skipLambdaParams = true // default false
        skipCatchParams = true // default false
    }
    allpublic {
        disabled = true // default false
        threshold = 4 // default 0
    } 
    setterfree {
        disabled = true // default false
        threshold = 5 // default 0
    }
    nomultiplereturn {
        disabled = true // default false
        threshold = 6 // default 0
    }
    inheritancefree {
        disabled = true // default false
        threshold = 7 // default 0
    }
}

Where x.y.z is actual version from gradle plugins

Invoke it:

./gradlew youshallnotpass

Maven

Add the plugin to the pom.xml

<plugin>
  <groupId>dev.youshallnotpass</groupId>
  <artifactId>youshallnotpass-maven-plugin</artifactId>
  <version>x.y.z</version>

  <!-- then configure it, if you need: -->
  <configuration>
    <offline>true</offline><!-- default false -->
    <nullfree>
      <disabled>true</disabled><!-- default false -->
      <threshold>3</threshold><!-- default 0 -->
      <skipComparisons>true</skipComparisons><!-- default false -->
    </nullfree>
    <staticfree>
      <disabled>true</disabled><!-- default false -->
      <threshold>2</threshold><!-- default 0 -->
    </staticfree>
    <allfinal>
      <disabled>true</disabled><!-- default false -->
      <threshold>1</threshold><!-- default 0 -->
      <skipInterfaceMethodParams>false</skipInterfaceMethodParams><!-- default true -->
      <skipLambdaParams>true</skipLambdaParams><!-- default false -->
      <skipCatchParams>true</skipCatchParams><!-- default false -->
    </allfinal>
    <allpublic>
      <disabled>true</disabled><!-- default false -->
      <threshold>4</threshold><!-- default 0 -->
    </allpublic>
    <setterfree>
      <disabled>true</disabled><!-- default false -->
      <threshold>5</threshold><!-- default 0 -->
    </setterfree>
    <nomultiplereturn>
      <disabled>true</disabled><!-- default false -->
      <threshold>6</threshold><!-- default 0 -->
    </nomultiplereturn>
    <inheritancefree>
      <disabled>true</disabled><!-- default false -->
      <threshold>7</threshold><!-- default 0 -->
    </inheritancefree>
  </configuration>
</plugin>

Invoke it:

mvn youshallnotpass:youshallnotpass

Where x.y.z is actual version from maven central

Inspections

1. ✅ NullFree (Why null is bad?) elegant code must not use the null keywords

2. ✅ StaticFree (Why static is bad?) elegant code must not use the static keywords

3. ✅ AllFinal every class, every field, every argument, every local variable must be final in the elegant code

4. 🔄 instanceoffree [in progress] elegant code must not use the instanceof keywords

5. ✅ inheritancefree elegant code must not use the class inheritance (when one class extends another one), only composition and type inheritance has been allowed

6. 🔄 enumfree [in progress] elegant code must not use the enums

7. 🔄 switchfree [in progress] elegant code must not use the switch blocks/expressions

8. ✅ NoMultipleReturn elegant code must contain only one (or no one) return in an any method

9. 🔄 getterfree [in progress] elegant code must not contain any getters

10. ✅ SetterFree elegant code must not contain any setters

11. ✅ AllPublic elegant code must use only public methods

12. 🔄 nopublicmethodnotoverrides [in progress] every public method in the elegant code must be overrided from an interface

NullFree

Plugin configuration options:

• skipComparisons allows use null in boolean expressions:

if (some == null) {
    ...
}

Can be suppressed in the code by @SuppressWarnings("nullfree")

StaticFree

Can be suppressed in the code by @SuppressWarnings("staticfree")

AllFinal

Plugin configuration options:

• skipInterfaceMethodParams allows restricting or not interface method parameter finals, by default there is no needed to set final for such places
• skipLambdaParams allows skip final in lambda parameters, by default lambda parameter needs to be final
• skipCatchParams allows skip final in catch parameters, by default catch parameter needs to be final

Can be suppressed in the code by @SuppressWarnings("allfinal")

AllPublic

Can be suppressed in the code by @SuppressWarnings("allpublic")

SetterFree

Can be suppressed in the code by @SuppressWarnings("setterfree")

NoMultipleReturn

Can be suppressed in the code by @SuppressWarnings("nomultiplereturn")

InheritanceFree

Can be suppressed in the code by @SuppressWarnings("inheritancefree")

Badges

If you use youshallnotpass plugin without offline = true settings, then you can attach the inspection badges to your readme file:

• ![nullfree status](https://youshallnotpass.dev/nullfree/<user>/<repo>)
• ![staticfree status](https://youshallnotpass.dev/staticfree/<user>/<repo>)
• ![allfinal status](https://youshallnotpass.dev/allfinal/<user>/<repo>)
• ![allpublic status](https://youshallnotpass.dev/allpublic/<user>/<repo>)
• ![setterfree status](https://youshallnotpass.dev/setterfree/<user>/<repo>)
• ![nomultiplereturn status](https://youshallnotpass.dev/nomultiplereturn/<user>/<repo>)
• ![inheritancefree status](https://youshallnotpass.dev/inheritancefree/<user>/<repo>)

Inspection threshold

Any inspection can be configured with threshold:

In gradle

youshallnotpass {
    ...
    staticfree {
        threshold = 19
    }
    ...
}

In maven

<configuration>
  <staticfree>
    <threshold>19</threshold>
  </staticfree>
</configuration>

Disabling inspections

Any inspection can be disabled by disabled settings:

In gradle

youshallnotpass {
    ...
    staticfree {
        disabled = true
    }
    ...
}

In maven

<configuration>
  <staticfree>
    <disabled>true</disabled>
  </staticfree>
</configuration>

All inspections are enabled by default.

Excluding files from inspects

There is global exclude settings, which can be used for defining exclude patterns: In gradle

youshallnotpass {
    exclude = ["glob:**/test/**/*Test.java"]
}

In maven

<configuration>
  <exclude>glob:**/test/**/*Test.java</exclude>
</configuration>

There is inspection local exclude configuration option, which has higher priority than global exclude configuration:

In gradle

nullfree {
    exclude = ["glob:**/*SomeBadFile.java"]
}

In maven

<nullfree>
  <exclude>glob:**/*SomeBadFile.java</exclude>
</nullfree>

License

MIT