Fix the usage of URLClassLoader

Author: komamitsu

build.gradle

@@ -10,7 +10,7 @@ repositories {
 }
 
 dependencies {
-    implementation group: 'com.google.inject', name: 'guice', version: '4.2.2'
+    implementation group: 'com.google.inject', name: 'guice', version: '5.1.0'
     implementation group: 'com.google.guava', name: 'guava', version: '31.0.1-jre'
     implementation group: 'com.moandjiezana.toml', name: 'toml4j', version: '0.7.2'
     implementation group: 'info.picocli', name: 'picocli', version: '4.1.4'

src/main/java/com/scalar/kelpie/modules/ModuleLoader.java

@@ -67,11 +67,9 @@ public List<Injector> loadInjectors() throws ModuleLoadException {
 
   private Module loadModule(String className, String jarPath) throws ModuleLoadException {
     try {
-      URLClassLoader classLoader = (URLClassLoader) Thread.currentThread().getContextClassLoader();
       URL jarUrl = new File(jarPath).toURI().toURL();
-      Method method = URLClassLoader.class.getDeclaredMethod("addURL", URL.class);
-      method.setAccessible(true);
-      method.invoke(classLoader, jarUrl);
+      URLClassLoader classLoader = new URLClassLoader(new URL[] { jarUrl }, Thread.currentThread().getContextClassLoader());
+      Thread.currentThread().setContextClassLoader(classLoader);
 
       @SuppressWarnings("unchecked")
       Class<Module> clazz = (Class<Module>) Class.forName(className, true, classLoader);