Remove generic usage in Api

api/base/src/main/java/org/geysermc/api/Api.java

@@ -34,10 +34,8 @@ import java.util.UUID;
 
 /**
  * The base API class.
- *
- * @param <S> the session type
  */
-public interface Api<S extends Session> {
+public interface Api {
 
     /**
      * Gets the session from the given
@@ -47,7 +45,7 @@ public interface Api<S extends Session> {
      * @return the session from the given UUID, if applicable
      */
     @Nullable
-    S sessionByUuid(@NonNull UUID uuid);
+    Session sessionByUuid(@NonNull UUID uuid);
 
     /**
      * Gets the session from the given
@@ -57,7 +55,7 @@ public interface Api<S extends Session> {
      * @return the session from the given UUID, if applicable
      */
     @Nullable
-    S sessionByXuid(@NonNull String xuid);
+    Session sessionByXuid(@NonNull String xuid);
 
     /**
      * Gets the session from the given
@@ -67,7 +65,7 @@ public interface Api<S extends Session> {
      * @return the session from the given name, if applicable
      */
     @Nullable
-    S sessionByName(@NonNull String name);
+    Session sessionByName(@NonNull String name);
 
     /**
      * Gets all the online sessions.
@@ -75,5 +73,5 @@ public interface Api<S extends Session> {
      * @return all the online sessions
      */
     @NonNull
-    List<S> onlineSessions();
+    List<? extends Session> onlineSessions();
 }

api/base/src/main/java/org/geysermc/api/Geyser.java

@@ -32,14 +32,14 @@ import org.checkerframework.checker.nullness.qual.NonNull;
  */
 @NonNull
 public class Geyser {
-    private static Api<?> api;
+    private static Api api;
 
     /**
      * Returns the base api.
      *
      * @return the base api
      */
-    public static Api<?> api() {
+    public static Api api() {
         if (api == null) {
             throw new RuntimeException("Api has not been registered yet!");
         }
@@ -55,7 +55,7 @@ public class Geyser {
      * @return the api of the given type
      */
     @SuppressWarnings("unchecked")
-    public static <T extends Api<?>> T api(@NonNull Class<T> apiClass) {
+    public static <T extends Api> T api(@NonNull Class<T> apiClass) {
         if (apiClass.isInstance(api)) {
             return (T) api;
         }
@@ -74,7 +74,7 @@ public class Geyser {
      *
      * @param api the api
      */
-    public static void set(@NonNull Api<?> api) {
+    public static void set(@NonNull Api api) {
         if (Geyser.api != null) {
             throw new RuntimeException("Cannot redefine already registered api!");
         }

api/geyser/pom.xml

@@ -17,6 +17,12 @@
     </properties>
 
     <dependencies>
+        <dependency>
+            <groupId>org.checkerframework</groupId>
+            <artifactId>checker-qual</artifactId>
+            <version>3.19.0</version>
+            <scope>provided</scope>
+        </dependency>
         <dependency>
             <groupId>org.geysermc</groupId>
             <artifactId>base-api</artifactId>

api/geyser/src/main/java/org/geysermc/geyser/api/GeyserApi.java

@@ -25,14 +25,20 @@
 
 package org.geysermc.geyser.api;
 
+import org.checkerframework.checker.nullness.qual.NonNull;
+import org.checkerframework.checker.nullness.qual.Nullable;
 import org.geysermc.api.Api;
 import org.geysermc.api.Geyser;
+import org.geysermc.api.session.Session;
 import org.geysermc.geyser.api.session.GeyserSession;
 
+import java.util.List;
+import java.util.UUID;
+
 /**
  * Represents the API used in Geyser.
  */
-public interface GeyserApi extends Api<GeyserSession> {
+public interface GeyserApi extends Api {
 
     /**
      * Shuts down the current Geyser instance.
@@ -52,6 +58,30 @@ public interface GeyserApi extends Api<GeyserSession> {
      */
     boolean productionEnvironment();
 
+    /**
+     * {@inheritDoc}
+     */
+    @Override
+    @Nullable GeyserSession sessionByUuid(@NonNull UUID uuid);
+
+    /**
+     * {@inheritDoc}
+     */
+    @Override
+    @Nullable GeyserSession sessionByXuid(@NonNull String xuid);
+
+    /**
+     * {@inheritDoc}
+     */
+    @Override
+    @Nullable GeyserSession sessionByName(@NonNull String name);
+
+    /**
+     * {@inheritDoc}
+     */
+    @NonNull
+    List<? extends GeyserSession> onlineSessions();
+
     /**
      * Gets the {@link GeyserApi}.
      *

core/src/main/java/org/geysermc/geyser/GeyserImpl.java

@@ -414,9 +414,8 @@ public class GeyserImpl implements GeyserApi {
     }
 
     @Override
-    @SuppressWarnings("unchecked")
+    public @NonNull List<GeyserSessionImpl> onlineSessions() {
-    public @NonNull List<GeyserSession> onlineSessions() {
+        return this.sessionManager.getAllSessions();
-        return (List<GeyserSession>) (List<? extends GeyserSession>) this.sessionManager.getAllSessions();
     }
 
     @Override