org.jboss.aerogear.sync.client

Interface ClientSynchronizer<T,S extends Edit<? extends Diff>>

Type Parameters:

T - The type of documents that this synchronizer can handle

S - The type of Edits that this synchronizer can handle

All Known Implementing Classes:

DiffMatchPatchClientSynchronizer, JsonMergePatchClientSynchronizer, JsonPatchClientSynchronizer

public interface ClientSynchronizer<T,S extends Edit<? extends Diff>>

An instance of this class will be able to handle tasks needed to implement Differential Synchronization for a specific type of documents.

Method Summary

Modifier and Type	Method and Description
void	addContent(T content, com.fasterxml.jackson.databind.node.ObjectNode objectNode, String fieldName) Adds the content of the passed in content to the ObjectNode.
S	clientDiff(ShadowDocument<T> shadowDocument, ClientDocument<T> document) Produces a Edit containing the changes between updated ShadowDocument and the ClientDocument.
PatchMessage<S>	createPatchMessage(String documentId, String clientId, Queue<S> edits) Creates a new PatchMessage with the with the type of Edit that this synchronizer can handle.
ClientDocument<T>	patchDocument(S edit, ClientDocument<T> document) Called when the document should be patched.
PatchMessage<S>	patchMessageFromJson(String json) Creates a {link PatchMessage} by parsing the passed-in json.
ShadowDocument<T>	patchShadow(S edit, ShadowDocument<T> shadowDocument) Called when the shadow should be patched.
S	serverDiff(ClientDocument<T> document, ShadowDocument<T> shadowDocument) Produces a Edit containing the changes between the updated ClientDocument and the ShadowDocument.

Method Detail

patchShadow

ShadowDocument<T> patchShadow(S edit,
                              ShadowDocument<T> shadowDocument)

Called when the shadow should be patched. Is called when an update is recieved.

Parameters:

edit - the Edit containing the diffs/patches

shadowDocument - the ShadowDocument to be patched

Returns:

ShadowDocument a new patched shadow document

patchDocument

ClientDocument<T> patchDocument(S edit,
                                ClientDocument<T> document)

Called when the document should be patched.

Parameters:

edit - the Edit containing the diffs/patches

document - the ClientDocument to be patched

Returns:

ClientDocument a new patched document.

serverDiff

S serverDiff(ClientDocument<T> document,
             ShadowDocument<T> shadowDocument)

Produces a Edit containing the changes between the updated ClientDocument and the ShadowDocument.

Calling the method is the first step in when starting a client side synchronization. We need to gather the changes between the updates made by the client and the shadow document. The produced Edit can then be passed to the server side.

Parameters:

document - the ClientDocument containing updates made by the client

shadowDocument - the ShadowDocument for the ClientDocument

Returns:

Edit the edit representing the diff between the client document and it's shadow document.

clientDiff

S clientDiff(ShadowDocument<T> shadowDocument,
             ClientDocument<T> document)

Produces a Edit containing the changes between updated ShadowDocument and the ClientDocument. This method would be called when the client receives an update from the server and need to produce an Edit to be able to patch the ClientDocument.

Parameters:

shadowDocument - the ShadowDocument patched with updates from the server

document - the ClientDocument

Returns:

Edit the edit representing the diff between the shadow document and the client document.

createPatchMessage

PatchMessage<S> createPatchMessage(String documentId,
                                   String clientId,
                                   Queue<S> edits)

Creates a new PatchMessage with the with the type of Edit that this synchronizer can handle.

Parameters:

documentId - the document identifier for the PatchMessage

clientId - the client identifier for the PatchMessage

edits - the Edits for the PatchMessage

Returns:

PatchMessage the created {code PatchMessage}

patchMessageFromJson

PatchMessage<S> patchMessageFromJson(String json)

Creates a {link PatchMessage} by parsing the passed-in json.

Parameters:

json - the json representation of a PatchMessage

Returns:

PatchMessage the created {code PatchMessage}

addContent

void addContent(T content,
                com.fasterxml.jackson.databind.node.ObjectNode objectNode,
                String fieldName)

Adds the content of the passed in content to the ObjectNode.

When a client initially adds a document to the engine it will also be sent across the wire to the server. Before sending, the content of the document has to be added to the JSON message payload. Different implementation will require different content types that the engine can handle and this give them control over how the content is added to the JSON ObjectNode. For example, a ClientEngine that stores simple text will just add the contents as a String, but one that stores JsonNode object will want to add its content as an object.

Parameters:

content - the content to be added

objectNode - the ObjectNode to add the content to

fieldName - the name of the field