Update logging mechanism in blank-java

- Instead of SLF4J logger, use Context's logger (removes SLF4J dependency)
- However, during unit testing, still requires SLF4J. Tests still show this logging option.
- Verified that Maven/Gradle builds don't generate SLF4J warnings.

Author: yualexan

sample-apps/blank-java/build.gradle

@@ -7,13 +7,13 @@ repositories {
 }
 
 dependencies {
-    implementation platform('software.amazon.awssdk:bom:2.10.73')
+    implementation platform('software.amazon.awssdk:bom:2.10.72')
     implementation platform('com.amazonaws:aws-xray-recorder-sdk-bom:2.4.0')
     implementation 'software.amazon.awssdk:lambda'
     implementation 'com.amazonaws:aws-xray-recorder-sdk-core'
     implementation 'com.amazonaws:aws-lambda-java-core:1.2.1'
     implementation 'com.amazonaws:aws-lambda-java-events:2.2.9'
-    runtimeOnly 'org.apache.logging.log4j:log4j-slf4j18-impl:[2.17.1,)'
+    implementation 'org.slf4j:slf4j-nop:2.0.6'
     testImplementation 'com.amazonaws:aws-lambda-java-tests:1.1.1'
     testImplementation 'org.junit.jupiter:junit-jupiter-api:5.8.2'
     testRuntimeOnly 'org.junit.jupiter:junit-jupiter-engine:5.8.2'

sample-apps/blank-java/pom.xml

@@ -23,10 +23,10 @@
       <version>2.2.9</version>
     </dependency>
     <dependency>
-      <groupId>org.apache.logging.log4j</groupId>
-      <artifactId>log4j-slf4j18-impl</artifactId>
-      <version>[2.17.1,)</version>
-    </dependency>
+      <groupId>org.slf4j</groupId>
+      <artifactId>slf4j-nop</artifactId>
+      <version>2.0.6</version>
+  </dependency>
     <dependency>
       <groupId>software.amazon.awssdk</groupId>
       <artifactId>lambda</artifactId>

sample-apps/blank-java/src/main/java/example/Handler.java

@@ -1,28 +1,26 @@
 package example;
 
 import com.amazonaws.services.lambda.runtime.Context;
+import com.amazonaws.services.lambda.runtime.LambdaLogger;
 import com.amazonaws.services.lambda.runtime.RequestHandler;
 
 import java.util.Map;
 
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
-
 import software.amazon.awssdk.services.lambda.LambdaClient;
 import software.amazon.awssdk.services.lambda.model.GetAccountSettingsResponse;
 import software.amazon.awssdk.services.lambda.model.LambdaException;
 
 // Handler value: example.Handler
 public class Handler implements RequestHandler<Map<String,String>, String> {
 
-    private static final Logger logger = LoggerFactory.getLogger(Handler.class);
     private static final LambdaClient lambdaClient = LambdaClient.builder().build();
 
     @Override
     public String handleRequest(Map<String,String> event, Context context) {
 
-        logger.info("ENVIRONMENT VARIABLES: " + System.getenv());
-        logger.info("EVENT: " + event);
+        LambdaLogger logger = context.getLogger();
+        logger.log("ENVIRONMENT VARIABLES: " + System.getenv());
+        logger.log("EVENT: " + event);
 
         GetAccountSettingsResponse response = null;
         try {

sample-apps/blank-java/src/main/resources/log4j2.xml

@@ -18,3 +18,13 @@ Resources:
         - AWSXrayWriteOnlyAccess
         - AWSLambdaVPCAccessExecutionRole
       Tracing: Active
+      Layers:
+        - !Ref libs
+  libs:
+    Type: AWS::Serverless::LayerVersion
+    Properties:
+      LayerName: blank-java-lib
+      Description: Dependencies for the blank-java sample app.
+      ContentUri: build/blank-java-lib.zip
+      CompatibleRuntimes:
+        - java11

sample-apps/blank-java/template-mvn.yml

@@ -27,4 +27,4 @@ Resources:
       Description: Dependencies for the blank-java sample app.
       ContentUri: build/blank-java-lib.zip
       CompatibleRuntimes:
-        - java8
+        - java11