com.google.protobuf

Class RepeatedFieldBuilder<MType extends GeneratedMessage,BType extends GeneratedMessage.Builder,IType extends MessageOrBuilder>

java.lang.Object

com.google.protobuf.RepeatedFieldBuilder<MType,BType,IType>

Type Parameters:

MType - the type of message for the field

BType - the type of builder for the field

IType - the common interface for the message and the builder

public class RepeatedFieldBuilder<MType extends GeneratedMessage,BType extends GeneratedMessage.Builder,IType extends MessageOrBuilder>
extends java.lang.Object

RepeatedFieldBuilder implements a structure that a protocol message uses to hold a repeated field of other protocol messages. It supports the classical use case of adding immutable Message's to the repeated field and is highly optimized around this (no extra memory allocations and sharing of immutable arrays).
It also supports the additional use case of adding a Message.Builder to the repeated 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 SingleFieldBuilder and RepeatedFieldBuilder classes cache messages that were created so that messages only need to be created when some change occured in its builder or a builder for one of its descendants.

Author:

jonp@google.com (Jon Perlow)

Constructor Summary

Constructors

Constructor and Description
RepeatedFieldBuilder(java.util.List<MType> messages, boolean isMessagesListMutable, com.google.protobuf.GeneratedMessage.BuilderParent parent, boolean isClean) Constructs a new builder with an empty list of messages.

Method Summary

Methods

Modifier and Type	Method and Description
RepeatedFieldBuilder<MType,BType,IType>	addAllMessages(java.lang.Iterable<? extends MType> values) Appends all of the messages in the specified collection to the end of this list, in the order that they are returned by the specified collection's iterator.
BType	addBuilder(int index, MType message) Inserts a new builder at the specified position in this list.
BType	addBuilder(MType message) Appends a new builder to the end of this list and returns the builder.
RepeatedFieldBuilder<MType,BType,IType>	addMessage(int index, MType message) Inserts the specified message at the specified position in this list.
RepeatedFieldBuilder<MType,BType,IType>	addMessage(MType message) Appends the specified element to the end of this list.
java.util.List<MType>	build() Builds the list of messages from the builder and returns them.
void	clear() Removes all of the elements from this list.
void	dispose()
BType	getBuilder(int index) Gets a builder for the specified index.
java.util.List<BType>	getBuilderList() Gets a view of the builder as a list of builders.
int	getCount() Gets the count of items in the list.
MType	getMessage(int index) Get the message at the specified index.
java.util.List<MType>	getMessageList() Gets a view of the builder as a list of messages.
IType	getMessageOrBuilder(int index) Gets the base class interface for the specified index.
java.util.List<IType>	getMessageOrBuilderList() Gets a view of the builder as a list of MessageOrBuilders.
boolean	isEmpty() Gets whether the list is empty.
void	markDirty() A builder becomes dirty whenever a field is modified -- including fields in nested builders -- and becomes clean when build() is called.
void	remove(int index) Removes the element at the specified position in this list.
RepeatedFieldBuilder<MType,BType,IType>	setMessage(int index, MType message) Sets a message at the specified index replacing the existing item at that index.

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

RepeatedFieldBuilder

public RepeatedFieldBuilder(java.util.List<MType> messages,
                    boolean isMessagesListMutable,
                    com.google.protobuf.GeneratedMessage.BuilderParent parent,
                    boolean isClean)

Constructs a new builder with an empty list of messages.

Parameters:

messages - the current list of messages

isMessagesListMutable - Whether the messages list is mutable

parent - a listener to notify of changes

isClean - whether the builder is initially marked clean

Method Detail

dispose

public void dispose()

getCount

public int getCount()

Gets the count of items in the list.

Returns:

the count of items in the list.

isEmpty

public boolean isEmpty()

Gets whether the list is empty.

Returns:

whether the list is empty

getMessage

public MType getMessage(int index)

Get the message at the specified index. If the message is currently stored as a Builder, it is converted to a Message by calling Message.Builder.buildPartial() on it.

Parameters:

index - the index of the message to get

Returns:

the message for the specified index

getBuilder

public BType getBuilder(int index)

Gets a builder for the specified index. If no builder has been created for that index, a builder is created on demand by calling Message.toBuilder().

Parameters:

index - the index of the message to get

Returns:

The builder for that index

getMessageOrBuilder

public IType getMessageOrBuilder(int index)

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

Parameters:

index - the index of the message to get

Returns:

the message or builder for the index as the base class interface

setMessage

public RepeatedFieldBuilder<MType,BType,IType> setMessage(int index,
                                                 MType message)

Sets a message at the specified index replacing the existing item at that index.

Parameters:

index - the index to set.

message - the message to set

Returns:

the builder

addMessage

public RepeatedFieldBuilder<MType,BType,IType> addMessage(MType message)

Appends the specified element to the end of this list.

Parameters:

message - the message to add

Returns:

the builder

addMessage

public RepeatedFieldBuilder<MType,BType,IType> addMessage(int index,
                                                 MType message)

Inserts the specified message at the specified position in this list. Shifts the element currently at that position (if any) and any subsequent elements to the right (adds one to their indices).

Parameters:

index - the index at which to insert the message

message - the message to add

Returns:

the builder

addAllMessages

public RepeatedFieldBuilder<MType,BType,IType> addAllMessages(java.lang.Iterable<? extends MType> values)

Appends all of the messages in the specified collection to the end of this list, in the order that they are returned by the specified collection's iterator.

Parameters:

values - the messages to add

Returns:

the builder

addBuilder

public BType addBuilder(MType message)

Appends a new builder to the end of this list and returns the builder.

Parameters:

message - the message to add which is the basis of the builder

Returns:

the new builder

addBuilder

public BType addBuilder(int index,
               MType message)

Inserts a new builder at the specified position in this list. Shifts the element currently at that position (if any) and any subsequent elements to the right (adds one to their indices).

Parameters:

index - the index at which to insert the builder

message - the message to add which is the basis of the builder

Returns:

the builder

remove

public void remove(int index)

Removes the element at the specified position in this list. Shifts any subsequent elements to the left (subtracts one from their indices). Returns the element that was removed from the list.

Parameters:

index - the index at which to remove the message

clear

public void clear()

Removes all of the elements from this list. The list will be empty after this call returns.

build

public java.util.List<MType> build()

Builds the list of messages from the builder and returns them.

Returns:

an immutable list of messages

getMessageList

public java.util.List<MType> getMessageList()

Gets a view of the builder as a list of messages. The returned list is live and will reflect any changes to the underlying builder.

Returns:

the messages in the list

getBuilderList

public java.util.List<BType> getBuilderList()

Gets a view of the builder as a list of builders. This returned list is live and will reflect any changes to the underlying builder.

Returns:

the builders in the list

getMessageOrBuilderList

public java.util.List<IType> getMessageOrBuilderList()

Gets a view of the builder as a list of MessageOrBuilders. This returned list is live and will reflect any changes to the underlying builder.

Returns:

the builders in the list

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 markAsDirty() 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.