Added artifact naming chapter

docs/artifact-naming.md

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+---
+title: Artifact Naming
+layout: default
+nav_order: 21
+---
+
+## Artifact Naming
+
+Artifacts in Maven are located along a 5 dimensional coordinate system.
+
+The three most fields are:
+
+* `groupId`
+* `artifactId`
+* `version`
+
+These fields are often also referred to as the **GAV**.
+
+* The groupId is typically a domain name such as `org.myorganization.mydepartment.myproject` and can thus be used to link an artifact to an organization in a Web-compatible way.
+* The artifactId is used as the name of a relevent unit of work within the group.
+* The version naturally is an identifier to capture a "snapshot" of that unit of work a certain point in time.
+
+The remaining two fields are:
+
+* `type`: The type of the artifact. Usually a filename extension such as `jar`, `zip` or `nt.bz2`.
+  As a Java-centric convention, if the type is left empty then it **defaults to `jar`**. So there is no "empty" type.
+* `classifier`: A custom string to discriminate further files published under the same GAV.
+
+### Syntax
+
+Maven coordinates are usually represented with the syntax `groupId:artifactId:version[:type[:classifier]]`.
+The `[]` indicate optional fields, so type and classifier may be omitted, but if a classifier is needed, then a type must be given as well.
+
+Obviously colons (`:`) must not be used within values for any of the fields.
+
+See Maven's [Guide to naming conventions](https://maven.apache.org/guides/mini/guide-naming-conventions.html) for details about how to choose proper values and the valid characters.
+
+### Maven Coordinates, Files and Relative URLs
+
+Maven coordinates can be unambigiously mapped to directory names and file names. These in turn correspond to relative URLs:
+
+* The `groupId` is turned into a directory prefix by replacing all `.` with `/`:
+* A filename is derived as follows:
+  * If the classifier is absent, then the pattern is `artifactId-[version].[type]`.
+  * Otherwise it is, `artifactId-[version]-[classifier].[type]`
+
+Example without classifier. Lets assume a monthly report is published as a PDF file.
+* Coordinate:    `org.example:report:2024.02.01:pdf`:
+* Translates to: `org/example/report-2024.02.01.pdf`
+
+
+Example with classifier. Let's assume a monthly report includes multiple files for different aspects such as sales.
+* Coordinate:    `org.example:report:2024.02.01:pptx:sales`:
+* Translates to: `org/example/report-2024.02.01-sales.pptx`
+
+### Resolution of Maven Coordinates
+
+A maven artifact's byte sequence is made accessible by forming an absolute URL from a repository's base URL with the artifacts relative URL.
+
+* Resolving `org.aksw.data.config.aksw-data-deployment:aksw-data-deployment:0.0.8:pom`
+* against `https://repo1.maven.org/maven2/`
+* yields https://repo1.maven.org/maven2/org/aksw/data/config/aksw-data-deployment/0.0.8/aksw-data-deployment-0.0.8.pom
+
+### Maven Coordinates and URNs
+
+While there is no official URN scheme for maven coordinates, they are naturally suitable for that purpose.
+
+In maven4data we use the prefix `urn:mvn:` to build urns such as `urn:mvn:org.example:report:2024.02.01:pdf`.
+
+### Maven URNs and the Semantic Web
+
+Maven URNs are suitable for direct use with RDF. The following example is valid RDF:
+
+```
+PREFIX dcat: <http://www.w3.org/ns/dcat#>
+
+<urn:mvn:org.example:report:2024.02.01:pdf#distribution>
+  dcat:downloadURL <urn:mvn:org.example:report:2024.02.01:pdf>  .
+```
+
+Now, it may not seem ideal to use a URN as a value of a property demanding a URL.
+The point is, that from this RDF document we can devise a simple transformation procedure to turn some or all URNs into resolvable HTTPS URLs!
+A simple build step can now be used to adjust the initial RDF document to create a version with actual download URLs.
+We may for example want to resolve all maven URNs that appear as values of `dcat:downloadURL` against `https://my.domain/files/`. The result is:
+
+
+```
+PREFIX dcat: <http://www.w3.org/ns/dcat#>
+
+<urn:mvn:org.example:report:2024.02.01:pdf#distribution>
+  dcat:downloadURL <https://my.domain/files/org/example/report/report-2024.02.01.pdf>  .
+```
+
+
+