1 // Protocol Buffers - Google's data interchange format
2 // Copyright 2008 Google Inc. All rights reserved.
3 // https://developers.google.com/protocol-buffers/
5 // Redistribution and use in source and binary forms, with or without
6 // modification, are permitted provided that the following conditions are
9 // * Redistributions of source code must retain the above copyright
10 // notice, this list of conditions and the following disclaimer.
11 // * Redistributions in binary form must reproduce the above
12 // copyright notice, this list of conditions and the following disclaimer
13 // in the documentation and/or other materials provided with the
15 // * Neither the name of Google Inc. nor the names of its
16 // contributors may be used to endorse or promote products derived from
17 // this software without specific prior written permission.
19 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
20 // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
21 // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
22 // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
23 // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
24 // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
25 // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
26 // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
27 // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
28 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
29 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
31 package com.google.protobuf;
34 * This class is used internally by the Protocol Buffer library and generated
35 * message implementations. It is public only because those generated messages
36 * do not reside in the {@code protobuf} package. Others should not use this
39 * This class contains constants and helper functions useful for dealing with
40 * the Protocol Buffer wire format.
42 * @author kenton@google.com Kenton Varda
44 public final class WireFormat {
45 // Do not allow instantiation.
46 private WireFormat() {}
48 public static final int WIRETYPE_VARINT = 0;
49 public static final int WIRETYPE_FIXED64 = 1;
50 public static final int WIRETYPE_LENGTH_DELIMITED = 2;
51 public static final int WIRETYPE_START_GROUP = 3;
52 public static final int WIRETYPE_END_GROUP = 4;
53 public static final int WIRETYPE_FIXED32 = 5;
55 static final int TAG_TYPE_BITS = 3;
56 static final int TAG_TYPE_MASK = (1 << TAG_TYPE_BITS) - 1;
58 /** Given a tag value, determines the wire type (the lower 3 bits). */
59 static int getTagWireType(final int tag) {
60 return tag & TAG_TYPE_MASK;
63 /** Given a tag value, determines the field number (the upper 29 bits). */
64 public static int getTagFieldNumber(final int tag) {
65 return tag >>> TAG_TYPE_BITS;
68 /** Makes a tag value given a field number and wire type. */
69 static int makeTag(final int fieldNumber, final int wireType) {
70 return (fieldNumber << TAG_TYPE_BITS) | wireType;
74 * Lite equivalent to {@link Descriptors.FieldDescriptor.JavaType}. This is
75 * only here to support the lite runtime and should not be used by users.
77 public enum JavaType {
84 BYTE_STRING(ByteString.EMPTY),
88 JavaType(final Object defaultDefault) {
89 this.defaultDefault = defaultDefault;
93 * The default default value for fields of this type, if it's a primitive
96 Object getDefaultDefault() {
97 return defaultDefault;
100 private final Object defaultDefault;
104 * Lite equivalent to {@link Descriptors.FieldDescriptor.Type}. This is
105 * only here to support the lite runtime and should not be used by users.
107 public enum FieldType {
108 DOUBLE (JavaType.DOUBLE , WIRETYPE_FIXED64 ),
109 FLOAT (JavaType.FLOAT , WIRETYPE_FIXED32 ),
110 INT64 (JavaType.LONG , WIRETYPE_VARINT ),
111 UINT64 (JavaType.LONG , WIRETYPE_VARINT ),
112 INT32 (JavaType.INT , WIRETYPE_VARINT ),
113 FIXED64 (JavaType.LONG , WIRETYPE_FIXED64 ),
114 FIXED32 (JavaType.INT , WIRETYPE_FIXED32 ),
115 BOOL (JavaType.BOOLEAN , WIRETYPE_VARINT ),
116 STRING (JavaType.STRING , WIRETYPE_LENGTH_DELIMITED) {
117 public boolean isPackable() { return false; }
119 GROUP (JavaType.MESSAGE , WIRETYPE_START_GROUP ) {
120 public boolean isPackable() { return false; }
122 MESSAGE (JavaType.MESSAGE , WIRETYPE_LENGTH_DELIMITED) {
123 public boolean isPackable() { return false; }
125 BYTES (JavaType.BYTE_STRING, WIRETYPE_LENGTH_DELIMITED) {
126 public boolean isPackable() { return false; }
128 UINT32 (JavaType.INT , WIRETYPE_VARINT ),
129 ENUM (JavaType.ENUM , WIRETYPE_VARINT ),
130 SFIXED32(JavaType.INT , WIRETYPE_FIXED32 ),
131 SFIXED64(JavaType.LONG , WIRETYPE_FIXED64 ),
132 SINT32 (JavaType.INT , WIRETYPE_VARINT ),
133 SINT64 (JavaType.LONG , WIRETYPE_VARINT );
135 FieldType(final JavaType javaType, final int wireType) {
136 this.javaType = javaType;
137 this.wireType = wireType;
140 private final JavaType javaType;
141 private final int wireType;
143 public JavaType getJavaType() { return javaType; }
144 public int getWireType() { return wireType; }
146 public boolean isPackable() { return true; }
149 // Field numbers for fields in MessageSet wire format.
150 static final int MESSAGE_SET_ITEM = 1;
151 static final int MESSAGE_SET_TYPE_ID = 2;
152 static final int MESSAGE_SET_MESSAGE = 3;
155 static final int MESSAGE_SET_ITEM_TAG =
156 makeTag(MESSAGE_SET_ITEM, WIRETYPE_START_GROUP);
157 static final int MESSAGE_SET_ITEM_END_TAG =
158 makeTag(MESSAGE_SET_ITEM, WIRETYPE_END_GROUP);
159 static final int MESSAGE_SET_TYPE_ID_TAG =
160 makeTag(MESSAGE_SET_TYPE_ID, WIRETYPE_VARINT);
161 static final int MESSAGE_SET_MESSAGE_TAG =
162 makeTag(MESSAGE_SET_MESSAGE, WIRETYPE_LENGTH_DELIMITED);