如何使用opentelemetry java sdk创建多个服务？

import io.opentelemetry.api.OpenTelemetry;
import io.opentelemetry.api.trace.Tracer;
import import io.opentelemetry.api.trace.propagation.W3CTraceContextPropagator;
import io.opentelemetry.context.propagation.ContextPropagators;
import io.opentelemetry.exporter.otlp.trace.OtlpGrpcSpanExporter;
import io.opentelemetry.sdk.OpenTelemetrySdk;
import io.opentelemetry.sdk.trace.export.BatchSpanProcessor;

public class MyService {
    public static void main(String[] args) {
        // 创建一个 OTLP gRPC 导出器
        OtlpGrpcSpanExporter exporter = OtlpGrpcSpanExporter.builder().build();

        // 创建一个批处理的 Span 处理器
        BatchSpanProcessor spanProcessor = BatchSpanProcessor.builder(exporter).build();

        // 创建一个 OpenTelemetry 实例
        OpenTelemetry openTelemetry = OpenTelemetrySdk.builder()
                .setTracerProvider(DefaultTracerProvider.builder()
                        .addSpanProcessor(spanProcessor)
                        .build())
                .setPropagators(ContextPropagators.create(W3CTraceContextPropagator.getInstance()))
                .build();

        // 获取一个 Tracer 实例
        Tracer tracer = openTelemetry.getTracer("my-service");

        // 在这里编写你的服务逻辑
        // ...
    }
}

import io.opentelemetry.api.trace.Span;
import io.opentelemetry.api.trace.Tracer;

public class MyService {
    public static void main(String[] args) {
        // 获取一个 Tracer 实例
        Tracer tracer = openTelemetry.getTracer("my-service");

        // 创建一个 Span
        Span span = tracer.spanBuilder("my-operation").startSpan();

        // 在这里编写你的服务逻辑
        // ...

        // 结束 Span
        span.end();
    }
}