public interface MessageLite extends MessageLiteOrBuilder
This interface is implemented by all protocol message objects. Non-lite messages additionally implement the Message interface, which is a subclass of MessageLite. Use MessageLite instead when you only need the subset of features which it supports -- namely, nothing that uses descriptors or reflection. You can instruct the protocol compiler to generate classes which implement only MessageLite, not the full Message interface, by adding the follow line to the .proto file:
option optimize_for = LITE_RUNTIME;
This is particularly useful on resource-constrained systems where the full protocol buffers runtime library is too big.
Note that on non-constrained systems (e.g. servers) when you need to link in lots of protocol
definitions, a better way to reduce total code footprint is to use optimize_for =
CODE_SIZE
. This will make the generated code smaller while still supporting all the same
features (at the expense of speed). optimize_for = LITE_RUNTIME
is best when you only
have a small number of message types linked into your binary, in which case the size of the
protocol buffers runtime itself is the biggest problem.
Modifier and Type | Interface and Description |
---|---|
static interface |
MessageLite.Builder
Abstract interface implemented by Protocol Message builders.
|
Modifier and Type | Method and Description |
---|---|
Parser<? extends MessageLite> |
getParserForType()
Gets the parser for a message of the same type as this message.
|
int |
getSerializedSize()
Get the number of bytes required to encode this message.
|
MessageLite.Builder |
newBuilderForType()
Constructs a new builder for a message of the same type as this message.
|
MessageLite.Builder |
toBuilder()
Constructs a builder initialized with the current message.
|
byte[] |
toByteArray()
Serializes the message to a
byte array and returns it. |
ByteString |
toByteString()
Serializes the message to a
ByteString and returns it. |
void |
writeDelimitedTo(java.io.OutputStream output)
Like
writeTo(OutputStream) , but writes the size of the message as a varint before
writing the data. |
void |
writeTo(CodedOutputStream output)
Serializes the message and writes it to
output . |
void |
writeTo(java.io.OutputStream output)
Serializes the message and writes it to
output . |
getDefaultInstanceForType, isInitialized
void writeTo(CodedOutputStream output) throws java.io.IOException
output
. This does not flush or close the
stream.java.io.IOException
int getSerializedSize()
Parser<? extends MessageLite> getParserForType()
ByteString toByteString()
ByteString
and returns it. This is just a trivial wrapper
around writeTo(CodedOutputStream)
.byte[] toByteArray()
byte
array and returns it. This is just a trivial wrapper
around writeTo(CodedOutputStream)
.void writeTo(java.io.OutputStream output) throws java.io.IOException
output
. This is just a trivial wrapper around
writeTo(CodedOutputStream)
. This does not flush or close the stream.
NOTE: Protocol Buffers are not self-delimiting. Therefore, if you write any more data to the
stream after the message, you must somehow ensure that the parser on the receiving end does not
interpret this as being part of the protocol message. This can be done e.g. by writing the size
of the message before the data, then making sure to limit the input to that size on the
receiving end (e.g. by wrapping the InputStream in one which limits the input). Alternatively,
just use writeDelimitedTo(OutputStream)
.
java.io.IOException
void writeDelimitedTo(java.io.OutputStream output) throws java.io.IOException
writeTo(OutputStream)
, but writes the size of the message as a varint before
writing the data. This allows more data to be written to the stream after the message without
the need to delimit the message data yourself. Use MessageLite.Builder.mergeDelimitedFrom(InputStream)
(or the static method YourMessageType.parseDelimitedFrom(InputStream)
) to parse messages written by this method.java.io.IOException
MessageLite.Builder newBuilderForType()
MessageLite.Builder toBuilder()