Merge pull request #21 from nebula-plugins/move-away-from-javapluginconvention

Remove usage of JavaPluginConvention which is deprecated and set to be removed in Gradle 8.0

Author: rpalcolea

src/main/kotlin/nebula/plugin/compile/JavaCrossCompilePlugin.kt

@@ -11,7 +11,6 @@ import org.gradle.api.Plugin
 import org.gradle.api.Project
 import org.gradle.api.file.FileCollection
 import org.gradle.api.plugins.JavaBasePlugin
-import org.gradle.api.plugins.JavaPluginConvention
 import org.gradle.api.plugins.JavaPluginExtension
 import org.gradle.api.provider.ProviderFactory
 import org.gradle.api.tasks.compile.JavaCompile
@@ -44,15 +43,17 @@ class JavaCrossCompilePlugin @Inject constructor(private val providerFactory: Pr
         if (!extension.enabled) {
             return
         }
-        val convention = project.convention.plugins["java"] as JavaPluginConvention? ?: return
-
         // Do not configure project if toolchains are used
-        val toolchain = project.extensions.getByType(JavaPluginExtension::class.java).toolchain
+        val javaPluginExtension = project.extensions.findByType(JavaPluginExtension::class.java)
+        if(javaPluginExtension == null) {
+            return
+        }
+        val toolchain = javaPluginExtension.toolchain
         if((toolchain as DefaultToolchainSpec).isConfigured) {
             project.logger.debug("Toolchain is configured for this project, skipping java-cross-compile plugin configuration")
             return
         }
-        val targetCompatibility = convention.targetCompatibility
+        val targetCompatibility = javaPluginExtension.targetCompatibility
         if (targetCompatibility < JavaVersion.current()) {
             with(project.tasks) {
                 val location by lazy { targetCompatibility.locate(project, providers) }