Use OpenTelemetry to report Java application data

Procedure

1. Open the pom.xml file and add JAR dependencies.

   <io.opentelemetry.version>0.12.0</io.opentelemetry.version>
   ...
   <dependency>
               <groupId>io.opentelemetry</groupId>
               <artifactId>opentelemetry-api</artifactId>
               <version>${io.opentelemetry.version}</version>
           </dependency>
   
           <dependency>
               <groupId>io.opentelemetry</groupId>
               <artifactId>opentelemetry-sdk-metrics</artifactId>
               <version>${io.opentelemetry.version}</version>
           </dependency>
   
           <dependency>
               <groupId>io.opentelemetry</groupId>
               <artifactId>opentelemetry-sdk-trace</artifactId>
               <version>${io.opentelemetry.version}</version>
           </dependency>
   
           <dependency>
               <groupId>io.opentelemetry</groupId>
               <artifactId>opentelemetry-sdk</artifactId>
               <version>${io.opentelemetry.version}</version>
           </dependency>
   
           <dependency>
               <groupId>io.opentelemetry</groupId>
               <artifactId>opentelemetry-exporter-jaeger</artifactId>
               <version>${io.opentelemetry.version}</version>
           </dependency>

2. Use a Jaeger exporter to report data.
   Use the initTracer() method to initialize the Tracer object. Then, use the myWonderfulUseCase() method to create a span based on the Tracer object and add instrumentation to the code.

   import io.grpc.*;
   import io.opentelemetry.api.trace.Span;
   import io.opentelemetry.api.trace.Tracer;
   import io.opentelemetry.exporter.jaeger.JaegerGrpcSpanExporter;
   import io.opentelemetry.sdk.OpenTelemetrySdk;
   import io.opentelemetry.sdk.trace.export.SimpleSpanProcessor;
   
   public class OpenTelemetryExample {
       // OTel API
       private Tracer tracer = null;
   
   
       private void initTracer(String name, int port, String auth) {
           // Create a channel towards Jaeger end point
           ManagedChannel jaegerChannel = ManagedChannelBuilder.forAddress(name, port).intercept(new ClientInterceptor() {
               @Override
               public <ReqT, RespT> ClientCall<ReqT, RespT> interceptCall(MethodDescriptor<ReqT, RespT> methodDescriptor, CallOptions callOptions, Channel channel) {
                   return new ForwardingClientCall.SimpleForwardingClientCall<ReqT, RespT>(
                           channel.newCall(methodDescriptor, callOptions)) {
                       @Override
                       public void start(Listener<RespT> responseListener, final Metadata headers) {
                           Metadata.Key<String> headerKey = Metadata.Key.of("Authentication", Metadata.ASCII_STRING_MARSHALLER);
                           headers.put(headerKey, auth);
                           super.start(responseListener, headers);
                       }
                   };
               }
           }).usePlaintext().build();
   
           // Export traces to Jaeger
           JaegerGrpcSpanExporter jaegerExporter =
                   JaegerGrpcSpanExporter.builder()
                           .setServiceName("otel-jaeger-example")
                           .setChannel(jaegerChannel)
                           .setDeadlineMs(30000)
                           .build();
   
           // Set to process the spans by the Jaeger Exporter
           OpenTelemetrySdk openTelemetry = OpenTelemetrySdk.builder().build();
           openTelemetry
                   .getTracerManagement()
                   .addSpanProcessor(SimpleSpanProcessor.builder(jaegerExporter).build());
   
   
           openTelemetry.getTracerManagement();
           tracer = openTelemetry.getTracer("io.opentelemetry.example.JaegerExample");
   
       }
   
       private void myWonderfulUseCase() {
           // Generate a span
           Span span = this.tracer.spanBuilder("Start my wonderful use case").startSpan();
           span.addEvent("Event 0");
           // execute my use case - here we simulate a wait
           doWork();
           span.addEvent("Event 1");
           span.end();
       }
   
       private void doWork() {
           try {
               Thread.sleep(1000);
           } catch (InterruptedException e) {
           }
       }
   
       public static void main(String[] args) {
   
           OpenTelemetryExample example = new OpenTelemetryExample();
           // please replease token from "http://tracing.console.aliyun.com/"
           example.initTracer("tracing-analysis-dc-bj.aliyuncs.com", 1883, "123@0yourToken_123@0yourToken");
           example.myWonderfulUseCase();
           // wait some seconds
           try {
               Thread.sleep(10000);
           } catch (InterruptedException e) {
           }
           System.out.println("Bye");
       }
   }

3. Download the demo project and replace the token in the project with the token that you obtain in the "Prerequisites" section of this topic.
4. Run the following command to run the demo:

   mvn clean compile exec:java -Dexec.mainClass=com.demo.OpenTelemetryExample

View data

Log on to the Tracing Analysis console. On the Applications page, click the newly created application. In this example, click the otel-jaeger-example application. Then, view the trace data of the application.