/**
* Called by {@code #mergeFieldFrom()} to parse a MessageSet extension. If {@code builder} is
* not null, this method will merge MessageSet into the builder. Otherwise, it will merge the
* MessageSet into {@code extensions}.
*/
private static void mergeMessageSetExtensionFromCodedStream(
CodedInputStream input,
UnknownFieldSet.Builder unknownFields,
ExtensionRegistryLite extensionRegistry,
Descriptor type,
Message.Builder builder,
FieldSet<FieldDescriptor> extensions)
throws IOException {
// The wire format for MessageSet is:
// message MessageSet {
// repeated group Item = 1 {
// required int32 typeId = 2;
// required bytes message = 3;
// }
// }
// "typeId" is the extension's field number. The extension can only be
// a message type, where "message" contains the encoded bytes of that
// message.
//
// In practice, we will probably never see a MessageSet item in which
// the message appears before the type ID, or where either field does not
// appear exactly once. However, in theory such cases are valid, so we
// should be prepared to accept them.
int typeId = 0;
ByteString rawBytes = null; // If we encounter "message" before "typeId"
ExtensionRegistry.ExtensionInfo extension = null;
// Read bytes from input, if we get it's type first then parse it eagerly,
// otherwise we store the raw bytes in a local variable.
while (true) {
final int tag = input.readTag();
if (tag == 0) {
break;
}
if (tag == WireFormat.MESSAGE_SET_TYPE_ID_TAG) {
typeId = input.readUInt32();
if (typeId != 0) {
// extensionRegistry may be either ExtensionRegistry or
// ExtensionRegistryLite. Since the type we are parsing is a full
// message, only a full ExtensionRegistry could possibly contain
// extensions of it. Otherwise we will treat the registry as if it
// were empty.
if (extensionRegistry instanceof ExtensionRegistry) {
extension =
((ExtensionRegistry) extensionRegistry).findExtensionByNumber(type, typeId);
}
}
} else if (tag == WireFormat.MESSAGE_SET_MESSAGE_TAG) {
if (typeId != 0) {
if (extension != null && ExtensionRegistryLite.isEagerlyParseMessageSets()) {
// We already know the type, so we can parse directly from the
// input with no copying. Hooray!
eagerlyMergeMessageSetExtension(
input, extension, extensionRegistry, builder, extensions);
rawBytes = null;
continue;
}
}
// We haven't seen a type ID yet or we want parse message lazily.
rawBytes = input.readBytes();
} else { // Unknown tag. Skip it.
if (!input.skipField(tag)) {
break; // End of group
}
}
}
input.checkLastTagWas(WireFormat.MESSAGE_SET_ITEM_END_TAG);
// Process the raw bytes.
if (rawBytes != null && typeId != 0) { // Zero is not a valid type ID.
if (extension != null) { // We known the type
mergeMessageSetExtensionFromBytes(
rawBytes, extension, extensionRegistry, builder, extensions);
} else { // We don't know how to parse this. Ignore it.
if (rawBytes != null) {
unknownFields.mergeField(
typeId, UnknownFieldSet.Field.newBuilder().addLengthDelimited(rawBytes).build());
}
}
}
}
/** Called by {@code #mergeFieldFrom()} to parse a MessageSet extension. */
private static void mergeMessageSetExtensionFromCodedStream(
final CodedInputStream input,
final UnknownFieldSet.Builder unknownFields,
final ExtensionRegistryLite extensionRegistry,
final Message.Builder builder)
throws IOException {
final Descriptor type = builder.getDescriptorForType();
// The wire format for MessageSet is:
// message MessageSet {
// repeated group Item = 1 {
// required int32 typeId = 2;
// required bytes message = 3;
// }
// }
// "typeId" is the extension's field number. The extension can only be
// a message type, where "message" contains the encoded bytes of that
// message.
//
// In practice, we will probably never see a MessageSet item in which
// the message appears before the type ID, or where either field does not
// appear exactly once. However, in theory such cases are valid, so we
// should be prepared to accept them.
int typeId = 0;
ByteString rawBytes = null; // If we encounter "message" before "typeId"
Message.Builder subBuilder = null;
FieldDescriptor field = null;
while (true) {
final int tag = input.readTag();
if (tag == 0) {
break;
}
if (tag == WireFormat.MESSAGE_SET_TYPE_ID_TAG) {
typeId = input.readUInt32();
// Zero is not a valid type ID.
if (typeId != 0) {
final ExtensionRegistry.ExtensionInfo extension;
// extensionRegistry may be either ExtensionRegistry or
// ExtensionRegistryLite. Since the type we are parsing is a full
// message, only a full ExtensionRegistry could possibly contain
// extensions of it. Otherwise we will treat the registry as if it
// were empty.
if (extensionRegistry instanceof ExtensionRegistry) {
extension =
((ExtensionRegistry) extensionRegistry).findExtensionByNumber(type, typeId);
} else {
extension = null;
}
if (extension != null) {
field = extension.descriptor;
subBuilder = extension.defaultInstance.newBuilderForType();
final Message originalMessage = (Message) builder.getField(field);
if (originalMessage != null) {
subBuilder.mergeFrom(originalMessage);
}
if (rawBytes != null) {
// We already encountered the message. Parse it now.
subBuilder.mergeFrom(CodedInputStream.newInstance(rawBytes.newInput()));
rawBytes = null;
}
} else {
// Unknown extension number. If we already saw data, put it
// in rawBytes.
if (rawBytes != null) {
unknownFields.mergeField(
typeId,
UnknownFieldSet.Field.newBuilder().addLengthDelimited(rawBytes).build());
rawBytes = null;
}
}
}
} else if (tag == WireFormat.MESSAGE_SET_MESSAGE_TAG) {
if (typeId == 0) {
// We haven't seen a type ID yet, so we have to store the raw bytes
// for now.
rawBytes = input.readBytes();
} else if (subBuilder == null) {
// We don't know how to parse this. Ignore it.
unknownFields.mergeField(
typeId,
UnknownFieldSet.Field.newBuilder().addLengthDelimited(input.readBytes()).build());
} else {
// We already know the type, so we can parse directly from the input
// with no copying. Hooray!
input.readMessage(subBuilder, extensionRegistry);
}
} else {
// Unknown tag. Skip it.
if (!input.skipField(tag)) {
break; // end of group
}
}
}
input.checkLastTagWas(WireFormat.MESSAGE_SET_ITEM_END_TAG);
if (subBuilder != null) {
builder.setField(field, subBuilder.build());
}
}
