For information only; in progress: builds with gradle 8.7 but does not publish assets.

build.gradle

@@ -1,56 +1,66 @@
-apply plugin: 'java'
-apply plugin: 'maven'
+plugins {
+	id 'java-library'
+	id 'maven-publish'
+}
 
 version='1.0.1-SNAPSHOT'
 group='com.simsilica'
 
+// Configuration to produce maven-repo style -sources and -javadoc jars
+java {
+    withJavadocJar()
+    withSourcesJar()
+}
+
 repositories {
     mavenLocal()
-    jcenter()
-
-    // Temporary until JME jars are in jcenter()   
-    maven { url "http://dl.bintray.com/jmonkeyengine/org.jmonkeyengine" }
+    mavenCentral()
+	// jcenter() is deprecated since Gradle 6.7 and will be removed in Gradle 9.0.
+	// see https://docs.gradle.org/8.7/userguide/upgrading_version_6.html#jcenter_deprecation
 }
 
 // Make sure the build file declares what it actually imports
-configurations.compile {
+configurations.implementation {
     transitive = false
 }
 
 // In this section you declare the dependencies for your production and test code
 dependencies {
 
-    compile "org.jmonkeyengine:jme3-core:3.1.+" 
-    //compile "com.jme3:jme3-core:unknown" 
-    compile 'org.slf4j:slf4j-api:1.7.13'
-
-    runtime files("assets")        
-}
-
+    implementation "org.jmonkeyengine:jme3-core:3.6.1-stable" 
+    //implementation "com.jme3:jme3-core:unknown" 
+    implementation 'org.slf4j:slf4j-api:1.7.13'
 
-// Configuration to produce maven-repo style -sources and -javadoc jars
-task sourcesJar(type: Jar) {
-    classifier = 'sources'
-    from sourceSets.main.allSource
-    exclude '**/.backups' 
+    runtimeOnly files("assets")        
 }
 
-task javadocJar(type: Jar, dependsOn: javadoc) {
-    classifier = 'javadoc'
-    from javadoc.destinationDir
-}
-
 task assetsJar(type: Jar) {
-    classifier = 'assets'
+    archiveClassifier = 'assets'
     from file('assets')
     exclude '**/*.psd' 
     exclude '**/.backups' 
 }
- 
+
 artifacts {
-    archives sourcesJar
-    archives javadocJar
-    archives assetsJar
+    assetsJar
+}
+
+// Publishing does not work for me without this stanza, and I don't know why 
+// not, which is not satisfactory. Even with it, publishing assets does not
+// work. The assets jar is built but is not copied to local maven. Copying
+// the file manually to local maven does then make it available to consumers,
+// but this is not good enough.
+publishing {
+    publications {
+        customLibrary(MavenPublication) {
+            from components.java
+        }
+        //artifact assetsJar
+    }
+
+    repositories {
+        mavenLocal()
+    }
 }