Add demo using async client (#3)

* Add example: Invoke with async client
* Add example: Invoke with streaming response

Author: sansmoraxz

example_code/src/main/java/aws/community/examples/InvokeBedrockAsync.java

@@ -0,0 +1,48 @@
+package aws.community.examples;
+
+import java.nio.charset.StandardCharsets;
+import java.util.concurrent.CompletableFuture;
+
+import org.json.JSONObject;
+
+import software.amazon.awssdk.core.SdkBytes;
+import software.amazon.awssdk.regions.Region;
+import software.amazon.awssdk.services.bedrockruntime.BedrockRuntimeAsyncClient;
+import software.amazon.awssdk.services.bedrockruntime.model.InvokeModelRequest;
+import software.amazon.awssdk.services.bedrockruntime.model.InvokeModelResponse;
+
+public class InvokeBedrockAsync {
+    public static void main(String[] args) {
+        BedrockRuntimeAsyncClient runtime = BedrockRuntimeAsyncClient.builder()
+                .region(Region.US_EAST_1)
+                .build();
+
+        String prompt = "Hello Claude, how are you?";
+
+        JSONObject jsonBody = new JSONObject()
+                .put("prompt", "Human: " + prompt + " Assistant:")
+                .put("temperature", 0.8)
+                .put("max_tokens_to_sample", 1024);
+
+        SdkBytes body = SdkBytes.fromUtf8String(
+               jsonBody.toString()
+        );
+
+        InvokeModelRequest request = InvokeModelRequest.builder()
+                .modelId("anthropic.claude-v2")
+                .body(body)
+                .build();
+
+        CompletableFuture<InvokeModelResponse> futureResponse = runtime.invokeModel(request);
+
+        JSONObject jsonObject = new JSONObject(
+                futureResponse.join().body().asString(StandardCharsets.UTF_8)
+        );
+
+        String completion = jsonObject.getString("completion");
+
+        System.out.println();
+        System.out.println(completion);
+        System.out.println();
+    }
+}

example_code/src/main/java/aws/community/examples/InvokeBedrockStreamingAsync.java

@@ -0,0 +1,72 @@
+package aws.community.examples;
+
+import java.nio.charset.StandardCharsets;
+import java.util.concurrent.CompletableFuture;
+
+import org.json.JSONObject;
+
+import software.amazon.awssdk.core.SdkBytes;
+import software.amazon.awssdk.regions.Region;
+import software.amazon.awssdk.services.bedrockruntime.BedrockRuntimeAsyncClient;
+import software.amazon.awssdk.services.bedrockruntime.model.InvokeModelWithResponseStreamRequest;
+import software.amazon.awssdk.services.bedrockruntime.model.InvokeModelWithResponseStreamResponseHandler;
+import software.amazon.awssdk.services.bedrockruntime.model.ResponseStream;
+
+public class InvokeBedrockStreamingAsync {
+    public static void main(String[] args) {
+        BedrockRuntimeAsyncClient runtime = BedrockRuntimeAsyncClient.builder()
+                .region(Region.US_EAST_1)
+                .build();
+
+        String prompt = "Explain large language models, like Anthropic Claude, in one short paragraph.";
+
+        JSONObject jsonBody = new JSONObject()
+                .put("prompt", "Human: " + prompt + " Assistant:")
+                .put("temperature", 0.8)
+                .put("max_tokens_to_sample", 2048);
+
+        SdkBytes body = SdkBytes.fromUtf8String(
+                jsonBody.toString());
+
+        InvokeModelWithResponseStreamRequest request = InvokeModelWithResponseStreamRequest.builder()
+                .modelId("anthropic.claude-v2")
+                .body(body)
+                .build();
+
+        InvokeModelWithResponseStreamResponseHandler.Visitor visitor = InvokeModelWithResponseStreamResponseHandler.Visitor
+                .builder()
+                .onChunk((chunk) -> {
+                    JSONObject jsonObject = new JSONObject(
+                            chunk.bytes().asString(StandardCharsets.UTF_8));
+
+                    System.out.print(jsonObject.getString("completion"));
+
+                })
+                .onDefault((event) -> {
+                    System.out.println("\n\nDefault: " + event.toString());
+                })
+                .build();
+
+        InvokeModelWithResponseStreamResponseHandler responseHandler = InvokeModelWithResponseStreamResponseHandler
+                .builder()
+                .onComplete(
+                        () -> System.out.println("\n\nCompleted streaming response."))
+                .onError(
+                        (error) -> System.out.println(
+                                "\n\nError streaming response: " + error.getMessage()))
+                .onEventStream((stream) -> {
+                    // print the response stream as it comes in
+                    stream.subscribe(
+                            (ResponseStream e) -> {
+                                e.accept(visitor);
+                            });
+                })
+                .build();
+
+        CompletableFuture<Void> futureResponse = runtime.invokeModelWithResponseStream(
+                request,
+                responseHandler);
+
+        futureResponse.join();
+    }
+}