Updated build.gradle to work with gradle 8.7

.gitignore

@@ -0,0 +1,3 @@
+.gradle/
+build/
+

build.gradle

@@ -1,43 +1,43 @@
-apply plugin: 'java'
-apply plugin: 'maven'
+plugins {
+    id 'java-library'
+    id 'maven-publish'
+}
+
+ext.jmeVersion='3.3.0-stable'
+
+ext.slf4jVersion = '1.7.32'
 
 version='1.0.1-SNAPSHOT'
 group='com.simsilica'
 
-ext.jmeVersion = "3.1.0-stable"
-
 repositories {
     mavenLocal()
-
-    if( JavaVersion.current() == JavaVersion.VERSION_1_7 ) {
-        // Fallback for JDK 7 that can no longer connect to jcenter with https
-        maven { url "http://jcenter.bintray.com" }
-    } else {
-        jcenter()
-    }
+    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:$jmeVersion"
-    compile 'org.slf4j:slf4j-api:1.7.13'
+    implementation "org.jmonkeyengine:jme3-core:$jmeVersion"
+    implementation 'org.slf4j:slf4j-api:1.7.13'
 }
 
 
 // Configuration to produce maven-repo style -sources and -javadoc jars
 task sourcesJar(type: Jar) {
-    classifier = 'sources'
+    archiveClassifier = 'sources'
     from sourceSets.main.allSource
     exclude '**/.backups'
 }
 
 task javadocJar(type: Jar, dependsOn: javadoc) {
-    classifier = 'javadoc'
+    archiveClassifier = 'javadoc'
     from javadoc.destinationDir
 }
 

gradle/wrapper/gradle-wrapper.properties

@@ -1,6 +1,7 @@
-#Fri Jan 29 13:36:50 EST 2016
-distributionBase=GRADLE_USER_HOME
-distributionPath=wrapper/dists
-zipStoreBase=GRADLE_USER_HOME
-zipStorePath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-2.10-bin.zip
+distributionBase=GRADLE_USER_HOME
+distributionPath=wrapper/dists
+distributionUrl=https\://services.gradle.org/distributions/gradle-8.7-bin.zip
+networkTimeout=10000
+validateDistributionUrl=true
+zipStoreBase=GRADLE_USER_HOME
+zipStorePath=wrapper/dists