Maple Java Style

Maple Java style

The fastest path is the OpenTelemetry Java Agent — it auto-instruments the JVM with zero code changes.

Zero-code: Java agent

curl -sLO https://github.com/open-telemetry/opentelemetry-java-instrumentation/releases/latest/download/opentelemetry-javaagent.jar

Inline the endpoint and ingest key as JVM args (these are the agent's only configuration surface — they map straight onto the inline-key model):

java \
  -javaagent:./opentelemetry-javaagent.jar \
  -Dotel.service.name=orders-api \
  -Dotel.exporter.otlp.protocol=http/protobuf \
  -Dotel.exporter.otlp.endpoint=https://ingest.maple.dev \
  -Dotel.exporter.otlp.headers="authorization=Bearer MAPLE_TEST" \
  -Dotel.resource.attributes="vcs.repository.url.full=https://github.com/acme/orders-api,vcs.ref.head.revision=${GITHUB_SHA:-}" \
  -jar build/libs/app.jar

Replace MAPLE_TEST with the project's real Maple ingest key once it's available. Keep the args inline (in Procfile / Dockerfile / systemd unit / application.yml) — don't move them behind unset env vars.

The agent auto-instruments Spring (Boot, MVC, WebFlux), Servlet containers, Apache HttpClient, OkHttp, JDBC, R2DBC, Hibernate, Kafka, gRPC, AWS SDK, and many more.

Manual SDK (when the agent isn't an option)

For cases where the agent can't run (GraalVM native image, embedded JVM, sealed module path), use the SDK directly:

<dependency>
  <groupId>io.opentelemetry</groupId>
  <artifactId>opentelemetry-api</artifactId>
</dependency>
<dependency>
  <groupId>io.opentelemetry</groupId>
  <artifactId>opentelemetry-sdk</artifactId>
</dependency>
<dependency>
  <groupId>io.opentelemetry</groupId>
  <artifactId>opentelemetry-exporter-otlp</artifactId>
</dependency>
<dependency>
  <groupId>io.opentelemetry.instrumentation</groupId>
  <artifactId>opentelemetry-logback-appender-1.0</artifactId>
</dependency>

public final class Telemetry {
    private static final String MAPLE_ENDPOINT = "https://ingest.maple.dev";
    private static final String MAPLE_KEY = "MAPLE_TEST"; // set by maple-onboard skill on pairing

    public static OpenTelemetrySdk init() {
        var headers = Map.of("authorization", "Bearer " + MAPLE_KEY);
        var resource = Resource.getDefault().merge(Resource.create(Attributes.builder()
            .put(ServiceAttributes.SERVICE_NAME, "orders-api")
            .put(DeploymentIncubatingAttributes.DEPLOYMENT_ENVIRONMENT_NAME,
                System.getenv().getOrDefault("DEPLOYMENT_ENV", "development"))
            .put("vcs.repository.url.full", "https://github.com/acme/orders-api")
            .put("vcs.ref.head.revision", System.getenv().getOrDefault("GITHUB_SHA", ""))
            .build()));

        var spanExporter = OtlpHttpSpanExporter.builder()
            .setEndpoint(MAPLE_ENDPOINT + "/v1/traces")
            .setHeaders(() -> headers)
            .build();
        // … same shape for OtlpHttpLogRecordExporter and OtlpHttpMetricExporter

        return OpenTelemetrySdk.builder()
            .setTracerProvider(SdkTracerProvider.builder()
                .addSpanProcessor(BatchSpanProcessor.builder(spanExporter).build())
                .setResource(resource)
                .build())
            .buildAndRegisterGlobal();
    }
}

Logs

Bridge the existing Logback / SLF4J / Log4j2 setup through OTLP — don't replace it. With the Java agent, log appenders are auto-bridged. With the manual SDK, add the opentelemetry-logback-appender-1.0 (or the Log4j 2 equivalent) and configure it in logback.xml so existing logger calls carry trace_id / span_id and reach Maple.

Bounded business spans

Acquire the tracer at class scope; wrap operations the agent's auto-instrumentation can't see.

private static final Tracer TRACER = GlobalOpenTelemetry.getTracer("orders.api");

public Order submit(String orderId, String tenantId) {
    var span = TRACER.spanBuilder("order.submit")
        .setAttribute("tenant.id", tenantId)
        .setAttribute("order.id", orderId)
        .startSpan();
    try (var scope = span.makeCurrent()) {
        return charge(orderId);
    } catch (Exception e) {
        span.recordException(e);
        span.setStatus(StatusCode.ERROR, e.getMessage());
        throw e;
    } finally {
        span.end();
    }
}

Coexistence

If the project already runs Datadog / New Relic / Honeycomb agents, leave them in place. The OpenTelemetry Java Agent coexists with most APMs (test the combination once before shipping). Don't strip an incumbent agent unless the user asks.