CloseWithHeadersMarker class

Author: panchenko

core/src/main/java/io/grpc/internal/CloseWithHeadersMarker.java

@@ -0,0 +1,15 @@
+package io.grpc.internal;
+
+import io.grpc.Status;
+
+/**
+ * Marker to be used in {@link Status#withCause(Throwable)} to signal that stream should be closed
+ * by sending headers.
+ */
+public class CloseWithHeadersMarker extends RuntimeException {
+
+  @Override
+  public synchronized Throwable fillInStackTrace() {
+    return this;
+  }
+}

core/src/main/java/io/grpc/internal/GrpcUtil.java

@@ -973,16 +973,6 @@ public static boolean getFlag(String envVarName, boolean enableByDefault) {
   }
 
 
-  /**
-   * Marker to be used in {@link Status#withCause(Throwable)} to signal that stream should be closed
-   * by sending headers.
-   */
-  public static final Throwable CLOSE_WITH_HEADERS = new Throwable("CLOSE_WITH_HEADERS") {
-    @Override
-    public synchronized Throwable fillInStackTrace() {
-      return this;
-    }
-  };
 
   private GrpcUtil() {}
 }

core/src/main/java/io/grpc/internal/ServerCallImpl.java

@@ -338,7 +338,7 @@ private void messagesAvailableInternal(final MessageProducer producer) {
             GrpcUtil.closeQuietly(producer);
             call.cancelled = true;
             call.handleInternalError(InternalStatus.asRuntimeExceptionWithoutStacktrace(
-                e.getStatus().withCause(GrpcUtil.CLOSE_WITH_HEADERS), null));
+                e.getStatus().withCause(new CloseWithHeadersMarker()), null));
             return;
           }
           message.close();

netty/src/main/java/io/grpc/netty/NettyServerStream.java

@@ -23,6 +23,7 @@
 import io.grpc.Metadata;
 import io.grpc.Status;
 import io.grpc.internal.AbstractServerStream;
+import io.grpc.internal.CloseWithHeadersMarker;
 import io.grpc.internal.GrpcUtil;
 import io.grpc.internal.StatsTraceContext;
 import io.grpc.internal.TransportTracer;
@@ -132,7 +133,7 @@ public void writeTrailers(Metadata trailers, boolean headersSent, Status status)
     public void cancel(Status status) {
       try (TaskCloseable ignore = PerfMark.traceTask("NettyServerStream$Sink.cancel")) {
         CancelServerStreamCommand cmd =
-            status.getCause() == GrpcUtil.CLOSE_WITH_HEADERS
+            status.getCause() instanceof CloseWithHeadersMarker
                 ? CancelServerStreamCommand.withReason(transportState(), status)
                 : CancelServerStreamCommand.withReset(transportState(), status);
         writeQueue.enqueue(cmd, true);