Fix minor Checkstyle violations

- Mostly missing JavaDoc, some line lengths

src/test/java/fr/xephi/authme/AuthMeMatchers.java

@@ -11,6 +11,7 @@ import java.util.Objects;
 /**
  * Custom matchers for AuthMe entities.
  */
+@SuppressWarnings("checkstyle:JavadocMethod") // Justification: Javadoc would be huge because of the many parameters
 public final class AuthMeMatchers {
 
     private AuthMeMatchers() {

src/test/java/fr/xephi/authme/ClassCollector.java

@@ -67,7 +67,7 @@ public class ClassCollector {
     public List<Class<?>> collectClasses(Predicate<Class<?>> filter) {
         File rootFolder = new File(root);
         List<Class<?>> collection = new ArrayList<>();
-        collectClasses(rootFolder, filter, collection);
+        gatherClassesFromFile(rootFolder, filter, collection);
         return collection;
     }
 
@@ -124,14 +124,14 @@ public class ClassCollector {
      * @param filter the class predicate
      * @param collection collection to add classes to
      */
-    private void collectClasses(File folder, Predicate<Class<?>> filter, List<Class<?>> collection) {
+    private void gatherClassesFromFile(File folder, Predicate<Class<?>> filter, List<Class<?>> collection) {
         File[] files = folder.listFiles();
         if (files == null) {
             throw new IllegalStateException("Could not read files from '" + folder + "'");
         }
         for (File file : files) {
             if (file.isDirectory()) {
-                collectClasses(file, filter, collection);
+                gatherClassesFromFile(file, filter, collection);
             } else if (file.isFile()) {
                 Class<?> clazz = loadTaskClassFromFile(file);
                 if (clazz != null && filter.test(clazz)) {

src/test/java/fr/xephi/authme/ReflectionTestUtils.java

@@ -82,7 +82,6 @@ public final class ReflectionTestUtils {
      * @param clazz the class to retrieve a method from
      * @param methodName the name of the method
      * @param parameterTypes the parameter types the method to retrieve has
-     *
      * @return the method of the class, set to be accessible
      */
     public static Method getMethod(Class<?> clazz, String methodName, Class<?>... parameterTypes) {
@@ -96,6 +95,15 @@ public final class ReflectionTestUtils {
         }
     }
 
+    /**
+     * Invokes the given method on the provided instance with the given parameters.
+     *
+     * @param method the method to invoke
+     * @param instance the instance to invoke the method on (null for static methods)
+     * @param parameters the parameters to pass to the method
+     * @param <V> return value of the method
+     * @return method return value
+     */
     @SuppressWarnings("unchecked")
     public static <V> V invokeMethod(Method method, Object instance, Object... parameters) {
         method.setAccessible(true);

src/test/java/fr/xephi/authme/data/limbo/LimboPlayerMatchers.java

@@ -14,6 +14,7 @@ import static org.hamcrest.collection.IsIterableContainingInOrder.contains;
 /**
  * Contains matchers for LimboPlayer.
  */
+@SuppressWarnings("checkstyle:JavadocMethod") // Justification: Javadoc would be huge because of the many parameters
 public final class LimboPlayerMatchers {
 
     private LimboPlayerMatchers() {
@@ -45,7 +46,8 @@ public final class LimboPlayerMatchers {
             @Override
             public void describeMismatchSafely(LimboPlayer item, Description description) {
                 description.appendText(format("Limbo with isOp=%s, groups={%s}, canFly=%s, walkSpeed=%f, flySpeed=%f",
-                    item.isOperator(), String.join(" ,", item.getGroups()), item.isCanFly(), item.getWalkSpeed(), item.getFlySpeed()));
+                    item.isOperator(), String.join(" ,", item.getGroups()), item.isCanFly(),
+                    item.getWalkSpeed(), item.getFlySpeed()));
             }
         };
     }

src/test/java/fr/xephi/authme/datasource/SqlDataSourceTestUtil.java

@@ -27,6 +27,15 @@ public final class SqlDataSourceTestUtil {
         return new MySQL(settings, hikariDataSource, extensionsFactory);
     }
 
+    /**
+     * Creates a SQLite implementation for testing purposes. Methods are overridden so the
+     * provided connection is never overridden.
+     *
+     * @param settings settings instance
+     * @param dataFolder data folder
+     * @param connection connection to use
+     * @return the created SQLite instance
+     */
     public static SQLite createSqlite(Settings settings, File dataFolder, Connection connection) {
         return new SQLite(settings, dataFolder, connection) {
             // Override reload() so it doesn't run SQLite#connect, since we're given a specific Connection to use