1 // Protocol Buffers - Google's data interchange format 2 // Copyright 2008 Google Inc. All rights reserved. 3 // 4 // Use of this source code is governed by a BSD-style 5 // license that can be found in the LICENSE file or at 6 // https://developers.google.com/open-source/licenses/bsd 7 8 package com.google.protobuf; 9 10 import java.io.IOException; 11 12 @ExperimentalApi 13 @CheckReturnValue 14 abstract class UnknownFieldSchema<T, B> { 15 16 static final int DEFAULT_RECURSION_LIMIT = 100; 17 18 @SuppressWarnings("NonFinalStaticField") 19 private static volatile int recursionLimit = DEFAULT_RECURSION_LIMIT; 20 21 /** Whether unknown fields should be dropped. */ shouldDiscardUnknownFields(Reader reader)22 abstract boolean shouldDiscardUnknownFields(Reader reader); 23 24 /** Adds a varint value to the unknown fields. */ addVarint(B fields, int number, long value)25 abstract void addVarint(B fields, int number, long value); 26 27 /** Adds a fixed32 value to the unknown fields. */ addFixed32(B fields, int number, int value)28 abstract void addFixed32(B fields, int number, int value); 29 30 /** Adds a fixed64 value to the unknown fields. */ addFixed64(B fields, int number, long value)31 abstract void addFixed64(B fields, int number, long value); 32 33 /** Adds a length delimited value to the unknown fields. */ addLengthDelimited(B fields, int number, ByteString value)34 abstract void addLengthDelimited(B fields, int number, ByteString value); 35 36 /** Adds a group value to the unknown fields. */ addGroup(B fields, int number, T subFieldSet)37 abstract void addGroup(B fields, int number, T subFieldSet); 38 39 /** Create a new builder for unknown fields. */ newBuilder()40 abstract B newBuilder(); 41 42 /** Returns an immutable instance of the field container. */ toImmutable(B fields)43 abstract T toImmutable(B fields); 44 45 /** 46 * Sets the unknown fields into the message. Caller must take care of the mutability of the 47 * fields. 48 */ setToMessage(Object message, T fields)49 abstract void setToMessage(Object message, T fields); 50 51 /** Get the unknown fields from the message. */ getFromMessage(Object message)52 abstract T getFromMessage(Object message); 53 54 /** Returns a builder for unknown fields in the message. */ getBuilderFromMessage(Object message)55 abstract B getBuilderFromMessage(Object message); 56 57 /** Sets an unknown field builder into the message. */ setBuilderToMessage(Object message, B builder)58 abstract void setBuilderToMessage(Object message, B builder); 59 60 /** Marks unknown fields as immutable. */ makeImmutable(Object message)61 abstract void makeImmutable(Object message); 62 63 /** Merges one field into the unknown fields. */ mergeOneFieldFrom(B unknownFields, Reader reader, int currentDepth)64 final boolean mergeOneFieldFrom(B unknownFields, Reader reader, int currentDepth) 65 throws IOException { 66 int tag = reader.getTag(); 67 int fieldNumber = WireFormat.getTagFieldNumber(tag); 68 switch (WireFormat.getTagWireType(tag)) { 69 case WireFormat.WIRETYPE_VARINT: 70 addVarint(unknownFields, fieldNumber, reader.readInt64()); 71 return true; 72 case WireFormat.WIRETYPE_FIXED32: 73 addFixed32(unknownFields, fieldNumber, reader.readFixed32()); 74 return true; 75 case WireFormat.WIRETYPE_FIXED64: 76 addFixed64(unknownFields, fieldNumber, reader.readFixed64()); 77 return true; 78 case WireFormat.WIRETYPE_LENGTH_DELIMITED: 79 addLengthDelimited(unknownFields, fieldNumber, reader.readBytes()); 80 return true; 81 case WireFormat.WIRETYPE_START_GROUP: 82 final B subFields = newBuilder(); 83 int endGroupTag = WireFormat.makeTag(fieldNumber, WireFormat.WIRETYPE_END_GROUP); 84 currentDepth++; 85 if (currentDepth >= recursionLimit) { 86 throw InvalidProtocolBufferException.recursionLimitExceeded(); 87 } 88 mergeFrom(subFields, reader, currentDepth); 89 currentDepth--; 90 if (endGroupTag != reader.getTag()) { 91 throw InvalidProtocolBufferException.invalidEndTag(); 92 } 93 addGroup(unknownFields, fieldNumber, toImmutable(subFields)); 94 return true; 95 case WireFormat.WIRETYPE_END_GROUP: 96 return false; 97 default: 98 throw InvalidProtocolBufferException.invalidWireType(); 99 } 100 } 101 mergeFrom(B unknownFields, Reader reader, int currentDepth)102 private final void mergeFrom(B unknownFields, Reader reader, int currentDepth) 103 throws IOException { 104 while (true) { 105 if (reader.getFieldNumber() == Reader.READ_DONE 106 || !mergeOneFieldFrom(unknownFields, reader, currentDepth)) { 107 break; 108 } 109 } 110 } 111 writeTo(T unknownFields, Writer writer)112 abstract void writeTo(T unknownFields, Writer writer) throws IOException; 113 writeAsMessageSetTo(T unknownFields, Writer writer)114 abstract void writeAsMessageSetTo(T unknownFields, Writer writer) throws IOException; 115 116 /** Merges {@code source} into {@code destination} and returns the merged instance. */ merge(T destination, T source)117 abstract T merge(T destination, T source); 118 119 /** Get the serialized size for message set serialization. */ getSerializedSizeAsMessageSet(T message)120 abstract int getSerializedSizeAsMessageSet(T message); 121 getSerializedSize(T unknowns)122 abstract int getSerializedSize(T unknowns); 123 124 /** 125 * Set the maximum recursion limit that ArrayDecoders will allow. An exception will be thrown if 126 * the depth of the message exceeds this limit. 127 */ setRecursionLimit(int limit)128 public void setRecursionLimit(int limit) { 129 recursionLimit = limit; 130 } 131 } 132