Add region tags in OTLP trace sample (#428)

Author: psx95

examples/otlptrace/build.gradle

@@ -25,12 +25,16 @@ description = 'Example showing OTLP exporter being used for traces export to GCP
 dependencies {
 	implementation(libraries.opentelemetry_api)
 	implementation(libraries.opentelemetry_sdk)
-	implementation(libraries.opentelemetry_otlp_exporter)
-	implementation(libraries.opentelemetry_sdk_autoconf)
+	// [START opentelemetry_autoconf_otlp_required_deps]
+	implementation("io.opentelemetry:opentelemetry-exporter-otlp:1.56.0")
+	implementation("io.opentelemetry:opentelemetry-sdk-extension-autoconfigure:1.56.0")
+	// [END opentelemetry_autoconf_otlp_required_deps]
 	implementation(libraries.opentelemetry_gcp_auth_extension)
 	implementation(libraries.opentelemetry_gcp_resources)
 }
 
+// [START opentelemetry_autoconf_otlp_config]
+// You can switch the desired protocol here by changing `otel.exporter.otlp.protocol`.
 def autoconf_config = [
 	'-Dotel.exporter.otlp.endpoint=https://telemetry.googleapis.com',
 	'-Dotel.traces.exporter=otlp',
@@ -40,8 +44,12 @@ def autoconf_config = [
 	'-Dotel.exporter.otlp.protocol=http/protobuf',
 	'-Dotel.java.global-autoconfigure.enabled=true',
 ]
+// [END opentelemetry_autoconf_otlp_config]
 
+// [START opentelemetry_autoconf_app_config]
 application {
 	mainClassName = 'com.google.cloud.opentelemetry.example.otlptrace.OTLPTraceExample'
+	// Pass the config as JVM arguments to the Java application
 	applicationDefaultJvmArgs = autoconf_config
 }
+// [END opentelemetry_autoconf_app_config]

examples/otlptrace/src/main/java/com/google/cloud/opentelemetry/example/otlptrace/OTLPTraceExample.java

@@ -17,8 +17,10 @@
 
 import io.opentelemetry.api.trace.Span;
 import io.opentelemetry.context.Scope;
+// [START opentelemetry_autoconf_essential_imports]
 import io.opentelemetry.sdk.OpenTelemetrySdk;
 import io.opentelemetry.sdk.autoconfigure.AutoConfiguredOpenTelemetrySdk;
+// [END opentelemetry_autoconf_essential_imports]
 import io.opentelemetry.sdk.common.CompletableResultCode;
 import java.util.Random;
 import java.util.concurrent.TimeUnit;
@@ -63,8 +65,10 @@ private static void doWork(String description) {
   }
 
   public static void main(String[] args) {
+    // [START opentelemetry_autoconf_configure_sdk]
     // Configure the OpenTelemetry pipeline with Auto configuration
     openTelemetrySdk = AutoConfiguredOpenTelemetrySdk.initialize().getOpenTelemetrySdk();
+    // [END opentelemetry_autoconf_configure_sdk]
 
     // Application-specific logic
     myUseCase("One");