Java: Support streaming on ChatCompletions (#2244)

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java/samples/sample-code/src/main/java/com/microsoft/semantickernel/samples/syntaxexamples/Example33_StreamingChat.java

@@ -0,0 +1,72 @@
+// Copyright (c) Microsoft. All rights reserved.
+package com.microsoft.semantickernel.samples.syntaxexamples;
+
+
+import com.azure.ai.openai.OpenAIAsyncClient;
+import com.microsoft.semantickernel.SamplesConfig;
+import com.microsoft.semantickernel.builders.SKBuilders;
+import com.microsoft.semantickernel.chatcompletion.ChatCompletion;
+import com.microsoft.semantickernel.chatcompletion.ChatHistory;
+import com.microsoft.semantickernel.exceptions.ConfigurationException;
+import reactor.core.publisher.Mono;
+
+import java.util.function.BiFunction;
+
+import static com.microsoft.semantickernel.chatcompletion.ChatHistory.AuthorRoles.Assistant;
+
+/**
+ * The following example shows how to use Semantic Kernel with Text Completion as streaming
+ */
+public class Example33_StreamingChat {
+    public static void main(String[] args) throws ConfigurationException {
+        StartStreamingChatAsync();
+    }
+
+    private static void StartStreamingChatAsync() throws ConfigurationException {
+        OpenAIAsyncClient client = SamplesConfig.getClient();
+
+        ChatCompletion chatCompletion = SKBuilders.chatCompletion().build(client, "gpt-35-turbo");
+
+        System.out.println("Chat content:");
+        System.out.println("------------------------");
+
+        var chatHistory = chatCompletion.createNewChat("You are a librarian, expert about books");
+        messageOutput(chatHistory);
+
+        // First user message
+        chatHistory.addMessage(ChatHistory.AuthorRoles.User, "Hi, I'm looking for book suggestions");
+        messageOutput(chatHistory);
+
+        // First bot assistant message
+        streamMessageOutputAsync(chatCompletion, chatHistory, Assistant);
+
+        // Second user message
+        chatHistory.addMessage(ChatHistory.AuthorRoles.User, "I love history and philosophy, I'd like to learn something new about Greece, any suggestion?");
+        messageOutput(chatHistory);
+
+        // Second bot assistant message
+        streamMessageOutputAsync(chatCompletion, chatHistory, Assistant);
+    }
+
+    private static void streamMessageOutputAsync(ChatCompletion chatGPT, ChatHistory chatHistory, ChatHistory.AuthorRoles authorRole) {
+        System.out.println(authorRole.name() + ": ");
+
+        BiFunction<String, String, String> agg = (o, o2) -> o + o2;
+
+        Mono<String> mono = chatGPT
+                .generateMessageStream(chatHistory, null)
+                .reduce("", agg);
+
+        String fullMessage = mono.block();
+        System.out.println(fullMessage);
+        System.out.println("\n------------------------");
+        chatHistory.addMessage(authorRole, fullMessage);
+    }
+
+    private static void messageOutput(ChatHistory chatHistory) {
+        var message = chatHistory.getMessages().get(chatHistory.getMessages().size() - 1);
+
+        System.out.println(message.getAuthorRoles().name() + " " + message.getContent());
+        System.out.println("------------------------");
+    }
+}