Class SingleFieldBuilderV3<MType,BType,IType> (3.19.4)

public class SingleFieldBuilderV3<MType,BType,IType> implements AbstractMessage.BuilderParent

SingleFieldBuilderV3 implements a structure that a protocol message uses to hold a single field of another protocol message. It supports the classical use case of setting an immutable Message as the value of the field and is highly optimized around this.

It also supports the additional use case of setting a Message.Builder as the field and deferring conversion of that Builder to an immutable Message. In this way, it's possible to maintain a tree of Builder's that acts as a fully read/write data structure.
Logically, one can think of a tree of builders as converting the entire tree to messages when build is called on the root or when any method is called that desires a Message instead of a Builder. In terms of the implementation, the SingleFieldBuilderV3 and RepeatedFieldBuilderV3 classes cache messages that were created so that messages only need to be created when some change occurred in its builder or a builder for one of its descendants.

Inheritance

java.lang.Object > SingleFieldBuilderV3<MType,BType,IType>

Implements

AbstractMessage.BuilderParent

Inherited Members

Object.clone()

Object.equals(Object)

Object.finalize()

Object.getClass()

Object.hashCode()

Object.notify()

Object.notifyAll()

Object.toString()

Object.wait()

Object.wait(long)

Object.wait(long,int)

Type Parameters
Name	Description
MType
BType
IType

Constructors

SingleFieldBuilderV3(MType message, AbstractMessage.BuilderParent parent, boolean isClean)

public SingleFieldBuilderV3(MType message, AbstractMessage.BuilderParent parent, boolean isClean)

Parameters
Name	Description
message	MType
parent	AbstractMessage.BuilderParent
isClean	boolean

Methods

build()

public MType build()

Builds the message and returns it.

Returns
Type	Description
MType	the message

clear()

public SingleFieldBuilderV3<MType,BType,IType> clear()

Clears the value of the field.

Returns
Type	Description
SingleFieldBuilderV3<MType,BType,IType>	the builder

dispose()

public void dispose()

getBuilder()

public BType getBuilder()

Gets a builder for the field. If no builder has been created yet, a builder is created on demand by calling Message#toBuilder.

Returns
Type	Description
BType	The builder for the field

getMessage()

public MType getMessage()

Get the message for the field. If the message is currently stored as a Builder, it is converted to a Message by calling Message.Builder#buildPartial on it. If no message has been set, returns the default instance of the message.

Returns
Type	Description
MType	the message for the field

getMessageOrBuilder()

public IType getMessageOrBuilder()

Gets the base class interface for the field. This may either be a builder or a message. It will return whatever is more efficient.

Returns
Type	Description
IType	the message or builder for the field as the base class interface

markDirty()

public void markDirty()

A builder becomes dirty whenever a field is modified -- including fields in nested builders -- and becomes clean when build() is called. Thus, when a builder becomes dirty, all its parents become dirty as well, and when it becomes clean, all its children become clean. The dirtiness state is used to invalidate certain cached values.

To this end, a builder calls markDirty() on its parent whenever it transitions from clean to dirty. The parent must propagate this call to its own parent, unless it was already dirty, in which case the grandparent must necessarily already be dirty as well. The parent can only transition back to "clean" after calling build() on all children.

mergeFrom(MType value)

public SingleFieldBuilderV3<MType,BType,IType> mergeFrom(MType value)

Merges the field from another field.

Parameter
Name	Description
value	MType the value to merge from

Returns
Type	Description
SingleFieldBuilderV3<MType,BType,IType>	the builder

setMessage(MType message)

public SingleFieldBuilderV3<MType,BType,IType> setMessage(MType message)

Sets a message for the field replacing any existing value.

Parameter
Name	Description
message	MType the message to set

Returns
Type	Description
SingleFieldBuilderV3<MType,BType,IType>	the builder