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[doc] Correct indentation so that the ordered list works,

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use callouts for the tips (instead of quotes)
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Andreas Dangel
2019-03-18 17:02:20 +01:00
parent 83990cf007
commit 4ec78b1970
1 changed files with 50 additions and 52 deletions
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docs/pages/pmd/devdocs/major_contributions/adding_new_cpd_language.md
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@@ -3,70 +3,68 @@ title: How to add a new CPD language
short_title: Add a new CPD language
tags: [devdocs, extending]
summary: How to add a new CPD language
last_updated: March 20, 2019
last_updated: March 18, 2019 (6.13.0)
permalink: pmd_devdocs_major_adding_new_cpd_language.html
author: Matías Fraga <fragamati@gmail.com>
---
First of all, thanks for the contribution!
Happily for you, to add CPD support for a new language is now easier than ever!
> **Pro Tip**: If you wish to add a new language, there are more than 50 languages you could easily add with just an [Antlr grammar](https://github.com/antlr/grammars-v4).
First of all, thanks for the contribution!
Happily for you, to add CPD support for a new language is now easier than ever!
{% include callout.html content="**Pro Tip**: If you wish to add a new language, there are more than 50 languages you could easily add with just an [Antlr grammar](https://github.com/antlr/grammars-v4)." type="primary" %}
All you need to do is follow this few steps:
All you need to do is follow this few steps:
1. Create a new module for your language, you can take [GO as an example](https://github.com/pmd/pmd/tree/master/pmd-go)
2. Create a Tokenizer
- For Antlr grammars you can take the grammar from [here](https://github.com/antlr/grammars-v4) and extend [AntlrTokenizer](https://github.com/pmd/pmd/blob/master/pmd-core/src/main/java/net/sourceforge/pmd/cpd/AntlrTokenizer.java) taking Go as an example
```java
public class GoTokenizer extends AntlrTokenizer {
@Override protected AntlrTokenManager getLexerForSource(SourceCode sourceCode) {
CharStream charStream = AntlrTokenizer.getCharStreamFromSourceCode(sourceCode);
return new AntlrTokenManager(new GolangLexer(charStream), sourceCode.getFileName());
- For Antlr grammars you can take the grammar from [here](https://github.com/antlr/grammars-v4) and extend [AntlrTokenizer](https://github.com/pmd/pmd/blob/master/pmd-core/src/main/java/net/sourceforge/pmd/cpd/AntlrTokenizer.java) taking Go as an example
```java
public class GoTokenizer extends AntlrTokenizer {
@Override protected AntlrTokenManager getLexerForSource(SourceCode sourceCode) {
CharStream charStream = AntlrTokenizer.getCharStreamFromSourceCode(sourceCode);
return new AntlrTokenManager(new GolangLexer(charStream), sourceCode.getFileName());
}
}
}
```
- For JavaCC grammars you should subclass [JavaCCTokenizer](https://github.com/pmd/pmd/blob/master/pmd-core/src/main/java/net/sourceforge/pmd/cpd/internal/JavaCCTokenizer.java) wich has many examples you could follow, you should also take the [Python implementation](https://github.com/pmd/pmd/blob/master/pmd-python/src/main/java/net/sourceforge/pmd/cpd/PythonTokenizer.java) as reference
- For any other scenario you can use [AnyTokenizer](https://github.com/pmd/pmd/blob/master/pmd-core/src/main/java/net/sourceforge/pmd/cpd/AnyTokenizer.java)
3. Create your [Language](https://github.com/pmd/pmd/blob/master/pmd-core/src/main/java/net/sourceforge/pmd/cpd/AbstractLanguage.java) class
```java
public class GoLanguage extends AbstractLanguage {
```
public GoLanguage() {
super("Go", "go", new GoTokenizer(), ".go");
}
}
```
- For JavaCC grammars you should subclass [JavaCCTokenizer](https://github.com/pmd/pmd/blob/master/pmd-core/src/main/java/net/sourceforge/pmd/cpd/internal/JavaCCTokenizer.java) wich has many examples you could follow, you should also take the [Python implementation](https://github.com/pmd/pmd/blob/master/pmd-python/src/main/java/net/sourceforge/pmd/cpd/PythonTokenizer.java) as reference
- For any other scenario you can use [AnyTokenizer](https://github.com/pmd/pmd/blob/master/pmd-core/src/main/java/net/sourceforge/pmd/cpd/AnyTokenizer.java)
> **Pro Tip**: Yes, keep looking at Go!
**You are almost there!**
3. Create your [Language](https://github.com/pmd/pmd/blob/master/pmd-core/src/main/java/net/sourceforge/pmd/cpd/AbstractLanguage.java) class
```java
public class GoLanguage extends AbstractLanguage {
public GoLanguage() {
super("Go", "go", new GoTokenizer(), ".go");
}
}
```
{% include callout.html content="**Pro Tip**: Yes, keep looking at Go!" type="primary" %}
**You are almost there!**
4. Please don't forget to add some test, you can again.. look at Go implementation ;)
If you read this far, I'm keen to think you would also love to support some extra CPD configuration (ignore imports or crazy things like that)
If that's your case , you came to the right place!
4. Please don't forget to add some test, you can again.. look at Go implementation ;)
If you read this far, I'm keen to think you would also love to support some extra CPD configuration (ignore imports or crazy things like that)
If that's your case , you came to the right place!
5. You can add your custom properties using a Token filter
- For Antlr grammars all you need to do is implement your own [AntlrTokenFilter](https://github.com/pmd/pmd/blob/master/pmd-core/src/main/java/net/sourceforge/pmd/cpd/token/AntlrTokenFilter.java)
And by now, I know where you are going to look...
**WRONG**
Why do you want GO to solve all your problems?
You should take a look to [Kotlin token filter implementation](https://github.com/pmd/pmd/blob/master/pmd-kotlin/src/main/java/net/sourceforge/pmd/cpd/KotlinTokenizer.java)
- For non-Antlr grammars you can use [BaseTokenFilter](https://github.com/pmd/pmd/blob/master/pmd-core/src/main/java/net/sourceforge/pmd/cpd/token/internal/BaseTokenFilter.java) directly or take a peek to [Java's token filter](https://github.com/pmd/pmd/blob/master/pmd-java/src/main/java/net/sourceforge/pmd/cpd/JavaTokenizer.java)
- For Antlr grammars all you need to do is implement your own [AntlrTokenFilter](https://github.com/pmd/pmd/blob/master/pmd-core/src/main/java/net/sourceforge/pmd/cpd/token/AntlrTokenFilter.java)
And by now, I know where you are going to look...
**WRONG**
Why do you want GO to solve all your problems?
You should take a look to [Kotlin token filter implementation](https://github.com/pmd/pmd/blob/master/pmd-kotlin/src/main/java/net/sourceforge/pmd/cpd/KotlinTokenizer.java)
- For non-Antlr grammars you can use [BaseTokenFilter](https://github.com/pmd/pmd/blob/master/pmd-core/src/main/java/net/sourceforge/pmd/cpd/token/internal/BaseTokenFilter.java) directly or take a peek to [Java's token filter](https://github.com/pmd/pmd/blob/master/pmd-java/src/main/java/net/sourceforge/pmd/cpd/JavaTokenizer.java)