chore: stream example for core util

Author: pankajagrawal16

java/CoreUtilities/Function/src/main/java/helloworld/AppStream.java

@@ -0,0 +1,25 @@
+package helloworld;
+
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.OutputStream;
+import java.util.Map;
+
+import com.amazonaws.services.lambda.runtime.Context;
+import com.amazonaws.services.lambda.runtime.RequestStreamHandler;
+import com.fasterxml.jackson.databind.ObjectMapper;
+import software.amazon.lambda.powertools.logging.Logging;
+import software.amazon.lambda.powertools.metrics.Metrics;
+
+public class AppStream implements RequestStreamHandler {
+    private static final ObjectMapper mapper = new ObjectMapper();
+
+    @Override
+    @Logging(logEvent = true)
+    @Metrics(namespace = "ServerlessAirline", service = "payment", captureColdStart = true)
+    public void handleRequest(InputStream input, OutputStream output, Context context) throws IOException {
+        Map map = mapper.readValue(input, Map.class);
+
+        System.out.println(map.size());
+    }
+}

java/CoreUtilities/template.yaml

@@ -34,6 +34,23 @@ Resources:
             Path: /hello
             Method: get
 
+  HelloWorldStreamFunction:
+    Type: AWS::Serverless::Function
+    Properties:
+      CodeUri: HelloWorldFunction
+      Handler: helloworld.AppStream::handleRequest
+      MemorySize: 512
+      Tracing: Active
+      Environment:
+        Variables:
+          POWERTOOLS_LOGGER_SAMPLE_RATE: 0.7
+      Events:
+        HelloWorld:
+          Type: Api
+          Properties:
+            Path: /hellostream
+            Method: get
+
 Outputs:
   # ServerlessRestApi is an implicit API created out of Events key under Serverless::Function
   # Find out more about other implicit resources you can reference within SAM