1 /* 2 * Copyright 2021 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; 18 19 import java.io.InputStream; 20 21 /** 22 * An extension of {@link InputStream} that allows the underlying data source to be detached and 23 * transferred to a new instance of the same kind. The detached InputStream takes over the 24 * ownership of the underlying data source. That's said, the detached InputStream is responsible 25 * for releasing its resources after use. The detached InputStream preserves internal states of 26 * the underlying data source. Data can be consumed through the detached InputStream as if being 27 * continually consumed through the original instance. The original instance discards internal 28 * states of detached data source and is no longer consumable as if the data source is exhausted. 29 * 30 * <p>A normal usage of this API is to extend the lifetime of the data source owned by the 31 * original instance for doing extra processing before releasing it. For example, when combined 32 * with {@link HasByteBuffer}, a custom {@link io.grpc.MethodDescriptor.Marshaller} can take 33 * over the ownership of buffers containing inbound data and perform delayed deserialization. 34 */ 35 public interface Detachable { 36 37 /** 38 * Detaches the underlying data source from this instance and transfers to an {@link 39 * InputStream}. Detaching data from an already-detached instance gives an InputStream with 40 * zero bytes of data. 41 * 42 */ detach()43 InputStream detach(); 44 } 45