chore!: Remove the old plugin API

Remove the now unused classes of the old plugin API. Move the
`getLoaderFor` helper function is moved to the `PluginFactory` which is
now the only caller.

Signed-off-by: Martin Nonnenmacher <[email protected]>

Author: mnonnenmacher

model/src/main/kotlin/config/AdvisorConfiguration.kt

@@ -22,7 +22,7 @@ package org.ossreviewtoolkit.model.config
 import com.fasterxml.jackson.annotation.JsonInclude
 
 import org.ossreviewtoolkit.plugins.api.PluginConfig
-import org.ossreviewtoolkit.utils.common.Plugin
+import org.ossreviewtoolkit.plugins.api.PluginDescriptor
 
 /**
  * The base configuration model of the advisor.
@@ -35,7 +35,7 @@ data class AdvisorConfiguration(
     val skipExcluded: Boolean = false,
 
     /**
-     * A map with [configuration][PluginConfig] for advice providers using the [provider type][Plugin.type] as key.
+     * A map with [configuration][PluginConfig] for advice providers using the [plugin id][PluginDescriptor.id] as key.
      */
     val config: Map<String, PluginConfig>? = null
 )

model/src/main/kotlin/config/ProviderPluginConfiguration.kt

@@ -21,20 +21,22 @@ package org.ossreviewtoolkit.model.config
 
 import com.fasterxml.jackson.annotation.JsonIgnore
 
-import org.ossreviewtoolkit.utils.common.ConfigurablePluginFactory
+import org.ossreviewtoolkit.plugins.api.PluginDescriptor
+import org.ossreviewtoolkit.plugins.api.PluginFactory
 import org.ossreviewtoolkit.utils.common.Options
-import org.ossreviewtoolkit.utils.common.Plugin
 
 /**
- * The configuration of provider [plugins][ConfigurablePluginFactory]. This class is used when multiple instances of the
+ * The configuration of provider [plugins][PluginFactory]. This class is used when multiple instances of the
  * same type of plugin should be configurable, like it is for example possible for package curation providers.
  * Therefore, each configured plugin gets a unique [id] in addition to the plugin [type] to be able to distinguish
  * different configurations for the same plugin type.
  */
 data class ProviderPluginConfiguration(
     /**
-     * The [type][Plugin.type] of the provider.
+     * The [id][PluginDescriptor.id] of the provider plugin.
      */
+    // TODO: Solve name conflict as this property refers to the plugin id, but this class already has an id property
+    //       which could be confusing.
     val type: String,
 
     /**

plugins/api/src/main/kotlin/PluginFactory.kt

@@ -19,7 +19,7 @@
 
 package org.ossreviewtoolkit.plugins.api
 
-import org.ossreviewtoolkit.utils.common.getLoaderFor
+import java.util.ServiceLoader
 
 /**
  * A factory interface for creating plugins of type [PLUGIN]. The different plugin endpoints ORT provides must inherit
@@ -56,3 +56,8 @@ interface PluginFactory<out PLUGIN : Plugin> {
 interface Plugin {
     val descriptor: PluginDescriptor
 }
+
+/**
+ * Return a [ServiceLoader] that is capable of loading services of type [T].
+ */
+inline fun <reified T : Any> getLoaderFor(): ServiceLoader<T> = ServiceLoader.load(T::class.java)