opentelemetry-java-instrumentation/examples/extension/src/main/java/com/example/javaagent/DemoSpanProcessor.java

/*
 * Copyright The OpenTelemetry Authors
 * SPDX-License-Identifier: Apache-2.0
 */

package com.example.javaagent;

import io.opentelemetry.context.Context;
import io.opentelemetry.sdk.common.CompletableResultCode;
import io.opentelemetry.sdk.trace.ReadWriteSpan;
import io.opentelemetry.sdk.trace.ReadableSpan;
import io.opentelemetry.sdk.trace.SpanProcessor;
import org.apache.commons.lang3.RandomStringUtils;

/**
 * See <a
 * href="https://github.com/open-telemetry/opentelemetry-specification/blob/master/specification/trace/sdk.md#span-processor">
 * OpenTelemetry Specification</a> for more information about {@link SpanProcessor}.
 *
 * @see DemoAutoConfigurationCustomizerProvider
 */
public class DemoSpanProcessor implements SpanProcessor {

  @Override
  public void onStart(Context parentContext, ReadWriteSpan span) {
    /*
    The sole purpose of this attribute is to introduce runtime dependency on some external library.
    We need this to demonstrate how extension can use them.
     */
    span.setAttribute("random", RandomStringUtils.random(10));
    span.setAttribute("custom", "demo");
  }

  @Override
  public boolean isStartRequired() {
    return true;
  }

  @Override
  public void onEnd(ReadableSpan span) {}

  @Override
  public boolean isEndRequired() {
    return false;
  }

  @Override
  public CompletableResultCode shutdown() {
    return CompletableResultCode.ofSuccess();
  }

  @Override
  public CompletableResultCode forceFlush() {
    return CompletableResultCode.ofSuccess();
  }
}