// Path: api/src/main/java/io/opencensus/trace/unsafe/ContextHandleUtils.java
// public class ContextHandleUtils {
// 
//   // No instance of this class.
//   private ContextHandleUtils() {}
// 
//   private static final Logger LOGGER = Logger.getLogger(ContextHandleUtils.class.getName());
//   private static final ContextManager CONTEXT_MANAGER =
//       loadContextManager(ContextManager.class.getClassLoader());
// 
//   private static ContextManager loadContextManager(@Nullable ClassLoader classLoader) {
//     try {
//       return Provider.createInstance(
//           Class.forName(
//               "io.opentelemetry.opencensusshim.OpenTelemetryContextManager",
//               /*initialize=*/ true,
//               classLoader),
//           ContextManager.class);
//     } catch (ClassNotFoundException e) {
//       LOGGER.log(
//           Level.FINE,
//           "Couldn't load full implementation for OpenTelemetry context manager, now loading "
//               + "original implementation.",
//           e);
//     }
//     return new ContextManagerImpl();
//   }
// 
//   public static ContextHandle currentContext() {
//     return CONTEXT_MANAGER.currentContext();
//   }
// 
//   /**
//    * Creates a new {@code ContextHandle} with the given value set.
//    *
//    * @param context the parent {@code ContextHandle}.
//    * @param span the value to be set.
//    * @return a new context with the given value set.
//    */
//   public static ContextHandle withValue(
//       ContextHandle context, @javax.annotation.Nullable Span span) {
//     return CONTEXT_MANAGER.withValue(context, span);
//   }
// 
//   /**
//    * Returns the value from the specified {@code ContextHandle}.
//    *
//    * @param context the specified {@code ContextHandle}.
//    * @return the value from the specified {@code ContextHandle}.
//    */
//   public static Span getValue(ContextHandle context) {
//     return CONTEXT_MANAGER.getValue(context);
//   }
// 
//   /**
//    * Attempts to pull the {@link io.grpc.Context} out of an OpenCensus {@code ContextHandle}.
//    *
//    * @return The context, or null if not a GRPC backed context handle.
//    */
//   @Nullable
//   public static Context tryExtractGrpcContext(ContextHandle handle) {
//     if (handle instanceof ContextHandleImpl) {
//       return ((ContextHandleImpl) handle).getContext();
//     }
//     // TODO: see if we can do something for the OpenTelemetry shim.
//     return null;
//   }
// }


import io.opencensus.trace.Span;
import io.opencensus.trace.SpanContext;
import io.opencensus.trace.unsafe.ContextHandleUtils;
import java.util.Collection;
import java.util.List;
import javax.annotation.Nullable;
import org.apache.logging.log4j.ThreadContext;
import org.apache.logging.log4j.core.config.Property;
import org.apache.logging.log4j.spi.ReadOnlyThreadContextMap;
import org.apache.logging.log4j.util.SortedArrayStringMap;
import org.apache.logging.log4j.util.StringMap;
  }

  static StringMap getContextAndTracingData() {
    SpanContext spanContext = getCurrentSpanContext();
    ReadOnlyThreadContextMap context = ThreadContext.getThreadContextMap();
    SortedArrayStringMap stringMap;
    if (context == null) {
      stringMap = new SortedArrayStringMap(ThreadContext.getImmutableContext());
    } else {
      StringMap contextData = context.getReadOnlyContextData();
      stringMap = new SortedArrayStringMap(contextData.size() + 3);
      stringMap.putAll(contextData);
    }
    // TODO(sebright): Move the calls to TraceId.toLowerBase16() and SpanId.toLowerBase16() out of
    // the critical path by wrapping the trace and span IDs in objects that call toLowerBase16() in
    // their toString() methods, after there is a fix for
    // https://github.com/census-instrumentation/opencensus-java/issues/1436.
    stringMap.putValue(
        OpenCensusTraceContextDataInjector.TRACE_ID_CONTEXT_KEY,
        spanContext.getTraceId().toLowerBase16());
    stringMap.putValue(
        OpenCensusTraceContextDataInjector.SPAN_ID_CONTEXT_KEY,
        spanContext.getSpanId().toLowerBase16());
    stringMap.putValue(
        OpenCensusTraceContextDataInjector.TRACE_SAMPLED_CONTEXT_KEY,
        spanContext.getTraceOptions().isSampled() ? "true" : "false");
    return stringMap;
  }

  private static SpanContext getCurrentSpanContext() {
// Path: api/src/main/java/io/opencensus/trace/unsafe/ContextHandleUtils.java
// public class ContextHandleUtils {
// 
//   // No instance of this class.
//   private ContextHandleUtils() {}
// 
//   private static final Logger LOGGER = Logger.getLogger(ContextHandleUtils.class.getName());
//   private static final ContextManager CONTEXT_MANAGER =
//       loadContextManager(ContextManager.class.getClassLoader());
// 
//   private static ContextManager loadContextManager(@Nullable ClassLoader classLoader) {
//     try {
//       return Provider.createInstance(
//           Class.forName(
//               "io.opentelemetry.opencensusshim.OpenTelemetryContextManager",
//               /*initialize=*/ true,
//               classLoader),
//           ContextManager.class);
//     } catch (ClassNotFoundException e) {
//       LOGGER.log(
//           Level.FINE,
//           "Couldn't load full implementation for OpenTelemetry context manager, now loading "
//               + "original implementation.",
//           e);
//     }
//     return new ContextManagerImpl();
//   }
// 
//   public static ContextHandle currentContext() {
//     return CONTEXT_MANAGER.currentContext();
//   }
// 
//   /**
//    * Creates a new {@code ContextHandle} with the given value set.
//    *
//    * @param context the parent {@code ContextHandle}.
//    * @param span the value to be set.
//    * @return a new context with the given value set.
//    */
//   public static ContextHandle withValue(
//       ContextHandle context, @javax.annotation.Nullable Span span) {
//     return CONTEXT_MANAGER.withValue(context, span);
//   }
// 
//   /**
//    * Returns the value from the specified {@code ContextHandle}.
//    *
//    * @param context the specified {@code ContextHandle}.
//    * @return the value from the specified {@code ContextHandle}.
//    */
//   public static Span getValue(ContextHandle context) {
//     return CONTEXT_MANAGER.getValue(context);
//   }
// 
//   /**
//    * Attempts to pull the {@link io.grpc.Context} out of an OpenCensus {@code ContextHandle}.
//    *
//    * @return The context, or null if not a GRPC backed context handle.
//    */
//   @Nullable
//   public static Context tryExtractGrpcContext(ContextHandle handle) {
//     if (handle instanceof ContextHandleImpl) {
//       return ((ContextHandleImpl) handle).getContext();
//     }
//     // TODO: see if we can do something for the OpenTelemetry shim.
//     return null;
//   }
// }


// Path: contrib/log_correlation/log4j2/src/main/java/io/opencensus/contrib/logcorrelation/log4j2/ContextDataUtils.java
import io.opencensus.trace.Span;
import io.opencensus.trace.SpanContext;
import io.opencensus.trace.unsafe.ContextHandleUtils;
import java.util.Collection;
import java.util.List;
import javax.annotation.Nullable;
import org.apache.logging.log4j.ThreadContext;
import org.apache.logging.log4j.core.config.Property;
import org.apache.logging.log4j.spi.ReadOnlyThreadContextMap;
import org.apache.logging.log4j.util.SortedArrayStringMap;
import org.apache.logging.log4j.util.StringMap;

  }

  static StringMap getContextAndTracingData() {
    SpanContext spanContext = getCurrentSpanContext();
    ReadOnlyThreadContextMap context = ThreadContext.getThreadContextMap();
    SortedArrayStringMap stringMap;
    if (context == null) {
      stringMap = new SortedArrayStringMap(ThreadContext.getImmutableContext());
    } else {
      StringMap contextData = context.getReadOnlyContextData();
      stringMap = new SortedArrayStringMap(contextData.size() + 3);
      stringMap.putAll(contextData);
    }
    // TODO(sebright): Move the calls to TraceId.toLowerBase16() and SpanId.toLowerBase16() out of
    // the critical path by wrapping the trace and span IDs in objects that call toLowerBase16() in
    // their toString() methods, after there is a fix for
    // https://github.com/census-instrumentation/opencensus-java/issues/1436.
    stringMap.putValue(
        OpenCensusTraceContextDataInjector.TRACE_ID_CONTEXT_KEY,
        spanContext.getTraceId().toLowerBase16());
    stringMap.putValue(
        OpenCensusTraceContextDataInjector.SPAN_ID_CONTEXT_KEY,
        spanContext.getSpanId().toLowerBase16());
    stringMap.putValue(
        OpenCensusTraceContextDataInjector.TRACE_SAMPLED_CONTEXT_KEY,
        spanContext.getTraceOptions().isSampled() ? "true" : "false");
    return stringMap;
  }

  private static SpanContext getCurrentSpanContext() {
    Span span = ContextHandleUtils.getValue(ContextHandleUtils.currentContext());