import io.opentracing.ScopeManager; //导入依赖的package包/类
/**
 * Creates a new Instana tracer with an implicit {@link ScopeManager} that is registered by the Java
 * {@link ServiceLoader}. If no scope manager is registered, this tracer will not offer support for active spans. To
 * set a scope manager explicitly, use {@link InstanaTracer#InstanaTracer(ScopeManager)}.
 */
public InstanaTracer() {
  ScopeManager scopeManager = null;
  try {
    Iterator<ScopeManager> it = ServiceLoader.load(ScopeManager.class).iterator();
    if (it.hasNext()) {
      scopeManager = it.next();
    }
  } catch (Exception ignored) {
  }
  if (scopeManager == null) {
    this.scopeManager = new InactiveScopeManager();
  } else {
    this.scopeManager = scopeManager;
  }
}
 

import io.opentracing.ScopeManager; //导入依赖的package包/类
public OpenTracingHystrixCallable(Callable<S> delegate, ScopeManager scopeManager, Span span) {
    if (span == null || delegate == null || scopeManager == null) {
        throw new NullPointerException();
    }
    this.delegateCallable = delegate;
    this.scopeManager = scopeManager;
    this.span = span;
}
 

import io.opentracing.ScopeManager; //导入依赖的package包/类
@Override
public ScopeManager scopeManager() {
    return tracer.scopeManager();
}
 

import io.opentracing.ScopeManager; //导入依赖的package包/类
@Override
public ScopeManager scopeManager() {
    return null;
}
 

import io.opentracing.ScopeManager; //导入依赖的package包/类
@Override
public Context<Span> getActiveContext() {
    ScopeManager scopeManager = GlobalTracer.get().scopeManager();
    return new ScopeContext(scopeManager.active(), true);
}
 

import io.opentracing.ScopeManager; //导入依赖的package包/类
@Override
public Context<Span> initializeNewContext(final Span span) {
    ScopeManager scopeManager = GlobalTracer.get().scopeManager();
    return new ScopeContext(span == null ? null : scopeManager.activate(span, false), false);
}
 

import io.opentracing.ScopeManager; //导入依赖的package包/类
@Override
public ScopeManager scopeManager() {
  return scopeManager;
}
 

import io.opentracing.ScopeManager; //导入依赖的package包/类
InstanaSpanBuilder(ScopeManager scopeManager, String operationName) {
  this.scopeManager = scopeManager;
  this.operationName = operationName;
  tags = new HashMap<String, String>();
}
 

import io.opentracing.ScopeManager; //导入依赖的package包/类
@Override public ScopeManager scopeManager() {
  return scopeManager;
}
 

import io.opentracing.ScopeManager; //导入依赖的package包/类
public MockTracer(ScopeManager scopeManager) {
    this(scopeManager, Propagator.TEXT_MAP);
}
 

import io.opentracing.ScopeManager; //导入依赖的package包/类
@Override
public ScopeManager scopeManager() {
    return this.scopeManager;
}
 

import io.opentracing.ScopeManager; //导入依赖的package包/类
@Override
public ScopeManager scopeManager() {
    return NoopScopeManager.INSTANCE;
}
 

import io.opentracing.ScopeManager; //导入依赖的package包/类
@Override
public ScopeManager scopeManager() {
	return delegate.scopeManager();
}
 

import io.opentracing.ScopeManager; //导入依赖的package包/类
@Override
public ScopeManager scopeManager() {
	return scopeManager;
}
 

import io.opentracing.ScopeManager; //导入依赖的package包/类
/**
 * By default, this builder uses BraveActiveSpanSource, which delegates management of the active
 * span to Brave and acts as a simple wrapper. You can override with any other implementation,
 * but beware that some implementations, e.g. opentracing-util's ThreadLocalActiveSpanSource,
 * may not tell Brave about the active span. In these scenarios, you would need to use the
 * OpenTracing APIs exclusively, as the Brave APIs would not function correctly, if at all.
 */
public Builder activeScopeManager(ScopeManager scopeManager) {
  if (scopeManager == null) throw new NullPointerException("scopeManager == null");
  this.scopeManager = scopeManager;
  return this;
}