1 /* 2 * Copyright 2014 The gRPC Authors 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 package io.grpc.netty; 18 19 import io.grpc.ExperimentalApi; 20 21 /** 22 * Identifies the negotiation used for starting up HTTP/2. 23 */ 24 @ExperimentalApi("https://github.com/grpc/grpc-java/issues/1784") 25 public enum NegotiationType { 26 /** 27 * Uses TLS ALPN/NPN negotiation, assumes an SSL connection. 28 */ 29 TLS, 30 31 /** 32 * Use the HTTP UPGRADE protocol for a plaintext (non-SSL) upgrade from HTTP/1.1 to HTTP/2. 33 */ 34 PLAINTEXT_UPGRADE, 35 36 /** 37 * Just assume the connection is plaintext (non-SSL) and the remote endpoint supports HTTP/2 38 * directly without an upgrade. 39 */ 40 PLAINTEXT 41 } 42