Java: Apply various fixes from API review (#5043)

### Motivation and Context

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### Description

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### Contribution Checklist

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- [ ] The code builds clean without any errors or warnings
- [ ] The PR follows the [SK Contribution
Guidelines](https://github.com/microsoft/semantic-kernel/blob/main/CONTRIBUTING.md)
and the [pre-submission formatting
script](https://github.com/microsoft/semantic-kernel/blob/main/CONTRIBUTING.md#development-scripts)
raises no violations
- [ ] All unit tests pass, and I have added new tests where possible
- [ ] I didn't break anyone 😄

java/aiservices/openai/src/main/java/com/microsoft/semantickernel/aiservices/openai/chatcompletion/OpenAIChatCompletion.java

@@ -19,10 +19,8 @@ import com.fasterxml.jackson.core.JsonProcessingException;
 import com.fasterxml.jackson.databind.JsonNode;
 import com.fasterxml.jackson.databind.ObjectMapper;
 import com.microsoft.semantickernel.Kernel;
-import com.microsoft.semantickernel.services.chatcompletion.AuthorRole;
-import com.microsoft.semantickernel.services.chatcompletion.ChatCompletionService;
-import com.microsoft.semantickernel.services.chatcompletion.ChatHistory;
-import com.microsoft.semantickernel.services.chatcompletion.ChatMessageContent;
+import com.microsoft.semantickernel.contextvariables.ContextVariable;
+import com.microsoft.semantickernel.contextvariables.ContextVariableTypes;
 import com.microsoft.semantickernel.exceptions.AIException;
 import com.microsoft.semantickernel.exceptions.SKException;
 import com.microsoft.semantickernel.hooks.KernelHooks;
@@ -30,15 +28,15 @@ import com.microsoft.semantickernel.hooks.PreChatCompletionEvent;
 import com.microsoft.semantickernel.orchestration.FunctionResult;
 import com.microsoft.semantickernel.orchestration.FunctionResultMetadata;
 import com.microsoft.semantickernel.orchestration.InvocationContext;
-import com.microsoft.semantickernel.semanticfunctions.KernelFunction;
-import com.microsoft.semantickernel.semanticfunctions.KernelFunctionArguments;
 import com.microsoft.semantickernel.orchestration.PromptExecutionSettings;
 import com.microsoft.semantickernel.orchestration.ToolCallBehavior;
-import com.microsoft.semantickernel.contextvariables.ContextVariable;
-import com.microsoft.semantickernel.contextvariables.ContextVariableTypes;
+import com.microsoft.semantickernel.semanticfunctions.KernelFunction;
+import com.microsoft.semantickernel.semanticfunctions.KernelFunctionArguments;
+import com.microsoft.semantickernel.services.chatcompletion.AuthorRole;
+import com.microsoft.semantickernel.services.chatcompletion.ChatCompletionService;
+import com.microsoft.semantickernel.services.chatcompletion.ChatHistory;
+import com.microsoft.semantickernel.services.chatcompletion.ChatMessageContent;
 import java.util.ArrayList;
-import java.util.Collections;
-import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
 import java.util.Objects;
@@ -53,10 +51,10 @@ public class OpenAIChatCompletion implements ChatCompletionService {
 
     private static final Logger LOGGER = LoggerFactory.getLogger(OpenAIChatCompletion.class);
     private final OpenAIAsyncClient client;
-    private final Map<String, ContextVariable<?>> attributes;
 
     @Nullable
     private final String serviceId;
+    private final String modelId;
 
     public OpenAIChatCompletion(
         OpenAIAsyncClient client,
@@ -64,19 +62,13 @@ public class OpenAIChatCompletion implements ChatCompletionService {
         @Nullable String serviceId) {
         this.serviceId = serviceId;
         this.client = client;
-        this.attributes = new HashMap<>();
-        attributes.put(MODEL_ID_KEY, ContextVariable.of(modelId));
+        this.modelId = modelId;
     }
 
     public static OpenAIChatCompletion.Builder builder() {
         return new OpenAIChatCompletion.Builder();
     }
 
-    @Override
-    public Map<String, ContextVariable<?>> getAttributes() {
-        return Collections.unmodifiableMap(attributes);
-    }
-
     @Override
     @Nullable
     public String getServiceId() {
@@ -430,6 +422,12 @@ public class OpenAIChatCompletion implements ChatCompletionService {
 
     }
 
+    @Nullable
+    @Override
+    public String getModelId() {
+        return modelId;
+    }
+
     public static class Builder extends ChatCompletionService.Builder {
 
         @Override

java/aiservices/openai/src/main/java/com/microsoft/semantickernel/aiservices/openai/textcompletion/OpenAITextGenerationService.java

@@ -26,9 +26,9 @@ import reactor.core.publisher.Mono;
 public class OpenAITextGenerationService implements TextGenerationService {
 
     private final OpenAIAsyncClient client;
-    private final Map<String, ContextVariable<?>> attributes;
     @Nullable
     private final String serviceId;
+    private final String modelId;
 
     /// <summary>
     /// Creates a new <see cref="OpenAITextGenerationService"/> client instance supporting AAD auth
@@ -45,19 +45,13 @@ public class OpenAITextGenerationService implements TextGenerationService {
         @Nullable String serviceId) {
         this.serviceId = serviceId;
         this.client = client;
-        attributes = new HashMap<>();
-        attributes.put(MODEL_ID_KEY, ContextVariable.of(modelId));
+        this.modelId = modelId;
     }
 
     public static Builder builder() {
         return new Builder();
     }
 
-    @Override
-    public Map<String, ContextVariable<?>> getAttributes() {
-        return Collections.unmodifiableMap(attributes);
-    }
-
     @Override
     @Nullable
     public String getServiceId() {
@@ -162,6 +156,12 @@ public class OpenAITextGenerationService implements TextGenerationService {
         return options;
     }
 
+    @Nullable
+    @Override
+    public String getModelId() {
+        return modelId;
+    }
+
     /**
      * Builder for a TextGenerationService
      */

java/samples/sample-code/src/main/java/com/microsoft/semantickernel/samples/syntaxexamples/Example62_CustomAIServiceSelector.java

@@ -12,7 +12,7 @@ import com.microsoft.semantickernel.orchestration.PromptExecutionSettings;
 import com.microsoft.semantickernel.semanticfunctions.KernelFunctionFromPrompt;
 import com.microsoft.semantickernel.services.AIService;
 import com.microsoft.semantickernel.services.AIServiceSelection;
-import com.microsoft.semantickernel.services.AiServiceCollection;
+import com.microsoft.semantickernel.services.AIServiceCollection;
 import com.microsoft.semantickernel.services.BaseAIServiceSelector;
 import com.microsoft.semantickernel.services.textcompletion.TextGenerationService;
 import java.util.Map;
@@ -84,7 +84,7 @@ public class Example62_CustomAIServiceSelector {
     // A dumb AIServiceSelector that just returns the first service and execution settings it finds
     static class CustomAIServiceSelector extends BaseAIServiceSelector {
 
-        public CustomAIServiceSelector(AiServiceCollection services) {
+        public CustomAIServiceSelector(AIServiceCollection services) {
             super(services);
         }
 

java/semantickernel-api/pom.xml

@@ -38,10 +38,6 @@
             <groupId>com.github.jknack</groupId>
             <artifactId>handlebars</artifactId>
         </dependency>
-        <dependency>
-            <groupId>io.projectreactor</groupId>
-            <artifactId>reactor-core</artifactId>
-        </dependency>
         <dependency>
             <groupId>com.google.code.findbugs</groupId>
             <artifactId>jsr305</artifactId>

java/semantickernel-api/src/main/java/com/microsoft/semantickernel/Kernel.java

@@ -10,7 +10,7 @@ import com.microsoft.semantickernel.plugin.KernelPlugin;
 import com.microsoft.semantickernel.services.AIService;
 import com.microsoft.semantickernel.services.AIServiceSelection;
 import com.microsoft.semantickernel.services.AIServiceSelector;
-import com.microsoft.semantickernel.services.AiServiceCollection;
+import com.microsoft.semantickernel.services.AIServiceCollection;
 import com.microsoft.semantickernel.services.OrderedAIServiceSelector;
 import com.microsoft.semantickernel.services.ServiceNotFoundException;
 import edu.umd.cs.findbugs.annotations.SuppressFBWarnings;
@@ -191,10 +191,10 @@ public class Kernel implements Buildable {
      */
     public static class Builder implements SemanticKernelBuilder<Kernel> {
 
-        private final AiServiceCollection services = new AiServiceCollection();
+        private final AIServiceCollection services = new AIServiceCollection();
         private final List<KernelPlugin> plugins = new ArrayList<>();
         @Nullable
-        private Function<AiServiceCollection, AIServiceSelector> serviceSelectorProvider;
+        private Function<AIServiceCollection, AIServiceSelector> serviceSelectorProvider;
 
         /**
          * Adds a service to the kernel.
@@ -224,7 +224,7 @@ public class Kernel implements Buildable {
          * @return {@code this} builder with the service selector provider set.
          */
         public Kernel.Builder withServiceSelector(
-            Function<AiServiceCollection, AIServiceSelector> serviceSelector) {
+            Function<AIServiceCollection, AIServiceSelector> serviceSelector) {
             this.serviceSelectorProvider = serviceSelector;
             return this;
         }

java/semantickernel-api/src/main/java/com/microsoft/semantickernel/services/AIService.java

@@ -1,90 +1,28 @@
 // Copyright (c) Microsoft. All rights reserved.
 package com.microsoft.semantickernel.services;
 
-import com.microsoft.semantickernel.contextvariables.ContextVariable;
-import java.util.Map;
 import javax.annotation.Nullable;
 
 /**
- * Marker interface for AI services. {@code AIService}s are registered with the {@code Kernel} 
- * and are used to provide access to AI services.
+ * Marker interface for AI services. {@code AIService}s are registered with the {@code Kernel} and
+ * are used to provide access to AI services.
  */
 public interface AIService {
 
     /**
-     * Gets the attributes of the service.
-     * @return The attributes of the service.
-     */
-    Map<String, ContextVariable<?>> getAttributes();
-
-    /**
-     * Key used to store the model identifier in the {@code attributes} map.
-     */
-    String MODEL_ID_KEY = "ModelId";
-
-    /**
-     * Key used to store the endpoint in the {@code attributes} map.
-     */
-    String ENDPOINT_KEY = "Endpoint";
-
-    /**
-     * Key used to store the API version in the {@code attributes} map.
-     */
-
-    String API_VERSION_KEY = "ApiVersion";
-
-    /**
-     * Gets the model identifier from the {@code attributes} map.
+     * Gets the model identifier.
      *
      * @return The model identifier if it was specified in the service's attributes; otherwise,
      * {@code null}.
      */
     @Nullable
-    default String getModelId() {
-        return getAttribute(this, MODEL_ID_KEY);
-    }
-
-    /**
-     * Gets the endpoint from the {@code attributes} map.
-     *
-     * @return The endpoint if it was specified in the service's attributes; otherwise, {@code null}.
-     */
-    @Nullable
-    default String getEndpoint() {
-        return getAttribute(this, ENDPOINT_KEY);
-    }
-
-    /**
-     * Gets the API version from the {@code attributes} map.
-     *
-     * @return The API version if it was specified in the service's attributes; otherwise, {@code null}.
-     */
-    @Nullable
-    default String getApiVersion() {
-        return getAttribute(this, API_VERSION_KEY);
-    }
+    String getModelId();
 
     /**
      * Gets the service identifier.
+     *
      * @return The service identifier.
      */
     @Nullable
     String getServiceId();
-
-    /**
-     * Get the named attribute from the service's attributes.
-     * @param service The service to get the attribute from.
-     * @param key The key of the attribute to get.
-     * @return The value of the attribute if it exists; otherwise, {@code null}.
-     */
-    @Nullable
-    static String getAttribute(AIService service, String key) {
-        if (service.getAttributes() != null) {
-            ContextVariable<?> contextVariable = service.getAttributes().get(key);
-            if (contextVariable != null) {
-                return contextVariable.getValue(String.class);
-            }
-        }
-        return null;
-    }
 }

java/semantickernel-api/src/main/java/com/microsoft/semantickernel/services/AIServiceCollection.java

@@ -2,6 +2,9 @@ package com.microsoft.semantickernel.services;
 
 import java.util.HashMap;
 
-public class AiServiceCollection extends HashMap<Class<? extends AIService>, AIService> {
+/**
+ * A collection of AI services.
+ */
+public class AIServiceCollection extends HashMap<Class<? extends AIService>, AIService> {
 
 }

java/semantickernel-api/src/main/java/com/microsoft/semantickernel/services/BaseAIServiceSelector.java

@@ -14,14 +14,14 @@ import javax.annotation.Nullable;
  */
 public abstract class BaseAIServiceSelector implements AIServiceSelector {
 
-    protected final AiServiceCollection services;
+    protected final AIServiceCollection services;
 
     /**
      * Initializes a new instance of the {@link BaseAIServiceSelector} class.
      *
      * @param services The services to select from.
      */
-    protected BaseAIServiceSelector(AiServiceCollection services) {
+    protected BaseAIServiceSelector(AIServiceCollection services) {
         this.services = services;
     }
 

java/semantickernel-api/src/main/java/com/microsoft/semantickernel/services/OrderedAIServiceSelector.java

@@ -29,7 +29,7 @@ public class OrderedAIServiceSelector extends BaseAIServiceSelector {
      * class with an empty collection of services.
      */
     public OrderedAIServiceSelector() {
-        super(new AiServiceCollection());
+        super(new AIServiceCollection());
     }
 
     /**
@@ -38,7 +38,7 @@ public class OrderedAIServiceSelector extends BaseAIServiceSelector {
      *
      * @param services The services to select from.
      */
-    public OrderedAIServiceSelector(AiServiceCollection services) {
+    public OrderedAIServiceSelector(AIServiceCollection services) {
         super(services);
     }
 

java/semantickernel-bom/pom.xml

@@ -128,11 +128,6 @@
                 <artifactId>handlebars</artifactId>
                 <version>4.3.1</version>
             </dependency>
-            <dependency>
-                <groupId>io.projectreactor</groupId>
-                <artifactId>reactor-core</artifactId>
-                <version>3.6.2</version>
-            </dependency>
             <dependency>
                 <groupId>jakarta.inject</groupId>
                 <artifactId>jakarta.inject-api</artifactId>

java/semantickernel-core/src/test/resources/Plugins/ExamplePlugins/ExampleFunctionWithService/config.json

@@ -1,14 +0,0 @@
-{
-  "schema": 1,
-  "description": "Sample plugin with a model and service id",
-  "type": "completion",
-  "completion": {
-    "max_tokens": 150,
-    "temperature": 0.9,
-    "top_p": 0.0,
-    "presence_penalty": 0.6,
-    "frequency_penalty": 0.0,
-    "service_id": "a-service-id",
-    "model_id": "a-model-id"
-  }
-}

java/semantickernel-core/src/test/resources/Plugins/ExamplePlugins/ExampleFunctionWithService/skprompt.txt

@@ -1 +0,0 @@
-Tell me a joke.