Document spotless formatting (including plugin and git hook setup)

doc/Coding-conventions.md

@@ -2,6 +2,10 @@
 
 We mainly follow the standard Java coding conventions and most of the conventions from the books _Effective Java_ [1] and _Clean Code_ [4]. Some exceptions and additional rules are listed below. Each rule starts with _DO_, _CONSIDER_, _AVOID_ or _DO NOT_, according to [2].
 
+## Automatic Formatting and Copyright Headers
+
+See [Build.md](Build.md). For the formatting rules, check [java-common.gradle.kts](https://github.com/ftsrg/theta/blob/master/buildSrc/src/main/kotlin/java-common.gradle.kts)
+
 ## Source files
 * **DO** encode files in UTF-8. **DO NOT** use any other format.
 

doc/Development.md

@@ -29,7 +29,30 @@ See [Build.md](Build.md).
 
 - Theta can be imported into [IntelliJ IDEA](https://www.jetbrains.com/idea/) as an existing Gradle project by selecting the _build.gradle.kts_ file in the root of the repository.
 - If you want to build the whole project (and not just run a single test for example), make sure to run the _build task of the whole project_. This can be done by opening the Gradle tab, and then selecting _theta / theta / Tasks / build / build_, right clicking and selecting _Run_.
-- Code styling and copyright noticing should be automatically set up for the ones accepted by the Github CI. It is not recommended to change them.
+- For code formatting and copyright header generation we use **spotless**.
+    - Locally, formatting can be done manually by `gradlew spotlessApply`
+    - Reformatting when saving a file can be set up by installing the `Spotless Applier` plugin (`Ctrl+Alt+s > Plugins`) and enabling it when saving (`Ctrl+Alt+s > Actions on Save`, enable `Run spotless`)
+    - On Linux, the following pre-commit hook can be used to disable commits without formatting:
+      ```
+      #!/bin/bash
+
+      # Run Spotless Check without interfering with uncommitted files
+      ./gradlew spotlessCheck 2>/dev/null 1>&2
+
+      # Capture the exit status of spotlessCheck
+      SPOTLESS_STATUS=$?
+
+      # If spotlessCheck fails, prevent the commit
+      if [ $SPOTLESS_STATUS -ne 0 ]; then
+        echo "Code format check failed. Please run './gradlew spotlessApply' to fix formatting issues."
+        exit 1
+      fi
+
+      # If spotlessCheck passes, proceed with the commit
+      echo "Spotless check passed."
+      exit 0
+      ```
+      *(write the above into `.git/hooks/pre-commit` and enable execution rights on the file)*
 
 ## Coding conventions