1 /* 2 * Copyright 2017 Google Inc. All rights reserved. 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 com.google.flatbuffers; 18 19 import static com.google.flatbuffers.Constants.*; 20 21 import java.nio.ByteBuffer; 22 23 /// @file 24 /// @addtogroup flatbuffers_java_api 25 /// @{ 26 27 /** 28 * Class that collects utility functions around `ByteBuffer`. 29 */ 30 public class ByteBufferUtil { 31 32 /** 33 * Extract the size prefix from a `ByteBuffer`. 34 * 35 * @param bb a size-prefixed buffer 36 * @return the size prefix 37 */ getSizePrefix(ByteBuffer bb)38 public static int getSizePrefix(ByteBuffer bb) { 39 return bb.getInt(bb.position()); 40 } 41 42 /** 43 * Create a duplicate of a size-prefixed `ByteBuffer` that has its position 44 * advanced just past the size prefix. 45 * 46 * @param bb a size-prefixed buffer 47 * @return a new buffer on the same underlying data that has skipped the 48 * size prefix 49 */ removeSizePrefix(ByteBuffer bb)50 public static ByteBuffer removeSizePrefix(ByteBuffer bb) { 51 ByteBuffer s = bb.duplicate(); 52 s.position(s.position() + SIZE_PREFIX_LENGTH); 53 return s; 54 } 55 56 } 57 58 /// @} 59