Clean up JavaPluginLoader and VelocityPluginModule (#1140)

proxy/src/main/java/com/velocitypowered/proxy/plugin/loader/java/JavaPluginLoader.java

@@ -63,7 +63,7 @@ public class JavaPluginLoader implements PluginLoader {
   public PluginDescription loadCandidate(Path source) throws Exception {
     Optional<SerializedPluginDescription> serialized = getSerializedPluginInfo(source);
 
-    if (!serialized.isPresent()) {
+    if (serialized.isEmpty()) {
       throw new InvalidPluginException("Did not find a valid velocity-plugin.json.");
     }
 
@@ -81,19 +81,21 @@ public class JavaPluginLoader implements PluginLoader {
       throw new IllegalArgumentException("Description provided isn't of the Java plugin loader");
     }
 
-    URL pluginJarUrl = candidate.getSource().get().toUri().toURL();
+    URL pluginJarUrl = candidate.getSource().orElseThrow(
+        () -> new InvalidPluginException("Description provided does not have a source path")
+    ).toUri().toURL();
     PluginClassLoader loader = AccessController.doPrivileged(
         (PrivilegedAction<PluginClassLoader>) () -> new PluginClassLoader(new URL[]{pluginJarUrl}));
     loader.addToClassloaders();
 
     JavaVelocityPluginDescriptionCandidate candidateInst =
         (JavaVelocityPluginDescriptionCandidate) candidate;
-    Class mainClass = loader.loadClass(candidateInst.getMainClass());
+    Class<?> mainClass = loader.loadClass(candidateInst.getMainClass());
     return createDescription(candidateInst, mainClass);
   }
 
   @Override
-  public Module createModule(PluginContainer container) throws Exception {
+  public Module createModule(PluginContainer container) {
     PluginDescription description = container.getDescription();
     if (!(description instanceof JavaVelocityPluginDescription)) {
       throw new IllegalArgumentException("Description provided isn't of the Java plugin loader");
@@ -102,11 +104,11 @@ public class JavaPluginLoader implements PluginLoader {
     JavaVelocityPluginDescription javaDescription = (JavaVelocityPluginDescription) description;
     Optional<Path> source = javaDescription.getSource();
 
-    if (!source.isPresent()) {
+    if (source.isEmpty()) {
       throw new IllegalArgumentException("No path in plugin description");
     }
 
-    return new VelocityPluginModule(server, javaDescription, container, baseDirectory);
+    return new VelocityPluginModule(javaDescription, container, baseDirectory);
   }
 
   @Override
@@ -184,7 +186,7 @@ public class JavaPluginLoader implements PluginLoader {
 
   private VelocityPluginDescription createDescription(
       JavaVelocityPluginDescriptionCandidate description,
-      Class mainClass) {
+      Class<?> mainClass) {
     return new JavaVelocityPluginDescription(
         description.getId(),
         description.getName().orElse(null),

proxy/src/main/java/com/velocitypowered/proxy/plugin/loader/java/VelocityPluginModule.java

@@ -23,7 +23,6 @@ import com.google.inject.Scopes;
 import com.velocitypowered.api.plugin.PluginContainer;
 import com.velocitypowered.api.plugin.PluginDescription;
 import com.velocitypowered.api.plugin.annotation.DataDirectory;
-import com.velocitypowered.api.proxy.ProxyServer;
 import java.nio.file.Path;
 import java.util.concurrent.ExecutorService;
 import net.kyori.adventure.text.logger.slf4j.ComponentLogger;
@@ -32,14 +31,12 @@ import org.slf4j.LoggerFactory;
 
 class VelocityPluginModule implements Module {
 
-  private final ProxyServer server;
   private final JavaVelocityPluginDescription description;
   private final PluginContainer pluginContainer;
   private final Path basePluginPath;
 
-  VelocityPluginModule(ProxyServer server, JavaVelocityPluginDescription description,
+  VelocityPluginModule(JavaVelocityPluginDescription description, PluginContainer pluginContainer,
-      PluginContainer pluginContainer, Path basePluginPath) {
+      Path basePluginPath) {
-    this.server = server;
     this.description = description;
     this.pluginContainer = pluginContainer;
     this.basePluginPath = basePluginPath;