Package org.apache.tinkerpop.gremlin.structure.io.graphson

Class GraphSONReader

java.lang.Object

org.apache.tinkerpop.gremlin.structure.io.graphson.GraphSONReader

All Implemented Interfaces:

GraphReader

public final class GraphSONReader
extends Object
implements GraphReader

A @{link GraphReader} that constructs a graph from a JSON-based representation of a graph and its elements. This implementation only supports JSON data types and is therefore lossy with respect to data types (e.g. a float will become a double, element IDs may not be retrieved in the format they were serialized, etc.). Edge and Vertex objects are serialized to Map instances. If an Element is used as a key, it is coerced to its identifier. Other complex objects are converted via Object.toString() unless there is a mapper serializer supplied.

Author:

Stephen Mallette (http://stephen.genoprime.com)

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static final class	GraphSONReader.Builder

Nested classes/interfaces inherited from interface org.apache.tinkerpop.gremlin.structure.io.GraphReader

GraphReader.ReaderBuilder<T extends GraphReader>

Method Summary

Modifier and Type	Method	Description
static GraphSONReader.Builder	build()
Edge	readEdge(InputStream inputStream, Function<Attachable<Edge>,Edge> edgeAttachMethod)	Read an Edge from output generated by GraphSONWriter.writeEdge(OutputStream, Edge) or via an Edge passed to GraphSONWriter.writeObject(OutputStream, Object).
void	readGraph(InputStream inputStream, Graph graphToWriteTo)	Read data into a Graph from output generated by any of the GraphSONWriter writeVertex or writeVertices methods or by GryoWriter.writeGraph(OutputStream, Graph).
<C> C	readObject(InputStream inputStream, Class<? extends C> clazz)	Reads an arbitrary object using the registered serializers.
Property	readProperty(InputStream inputStream, Function<Attachable<Property>,Property> propertyAttachMethod)	Read a Property from output generated by GraphSONWriter.writeProperty(OutputStream, Property) or via an Property passed to GraphSONWriter.writeObject(OutputStream, Object).
Vertex	readVertex(InputStream inputStream, Function<Attachable<Vertex>,Vertex> vertexAttachMethod)	Read a Vertex from output generated by any of the GraphSONWriter writeVertex or writeVertices methods or by GraphSONWriter.writeGraph(OutputStream, Graph).
Vertex	readVertex(InputStream inputStream, Function<Attachable<Vertex>,Vertex> vertexAttachMethod, Function<Attachable<Edge>,Edge> edgeAttachMethod, Direction attachEdgesOfThisDirection)	Read a Vertex from output generated by any of the GraphSONWriter writeVertex or writeVertices methods or by GraphSONWriter.writeGraph(OutputStream, Graph).
VertexProperty	readVertexProperty(InputStream inputStream, Function<Attachable<VertexProperty>,VertexProperty> vertexPropertyAttachMethod)	Read a VertexProperty from output generated by GraphSONWriter.writeVertexProperty(OutputStream, VertexProperty) or via an VertexProperty passed to GraphSONWriter.writeObject(OutputStream, Object).
Iterator<Vertex>	readVertices(InputStream inputStream, Function<Attachable<Vertex>,Vertex> vertexAttachMethod, Function<Attachable<Edge>,Edge> edgeAttachMethod, Direction attachEdgesOfThisDirection)	Read Vertex objects from output generated by any of the GraphSONWriter writeVertex or writeVertices methods or by GraphSONWriter.writeGraph(OutputStream, Graph).

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.apache.tinkerpop.gremlin.structure.io.GraphReader

readVertex

Method Details

readGraph

public void readGraph(InputStream inputStream,
 Graph graphToWriteTo)
               throws IOException

Read data into a Graph from output generated by any of the GraphSONWriter writeVertex or writeVertices methods or by GryoWriter.writeGraph(OutputStream, Graph).

Specified by:

readGraph in interface GraphReader

Parameters:

inputStream - a stream containing an entire graph of vertices and edges as defined by the accompanying GraphSONWriter.writeGraph(OutputStream, Graph).

graphToWriteTo - the graph to write to when reading from the stream.

Throws:

IOException

readVertices

public Iterator<Vertex> readVertices(InputStream inputStream,
 Function<Attachable<Vertex>,Vertex> vertexAttachMethod,
 Function<Attachable<Edge>,Edge> edgeAttachMethod,
 Direction attachEdgesOfThisDirection)
                              throws IOException

Read Vertex objects from output generated by any of the GraphSONWriter writeVertex or writeVertices methods or by GraphSONWriter.writeGraph(OutputStream, Graph).

Specified by:

readVertices in interface GraphReader

Parameters:

inputStream - a stream containing at least one Vertex as defined by the accompanying GraphWriter.writeVertices(OutputStream, Iterator, Direction) or GraphWriter.writeVertices(OutputStream, Iterator) methods.

vertexAttachMethod - a function that creates re-attaches a Vertex to a Host object.

edgeAttachMethod - a function that creates re-attaches a Edge to a Host object.

attachEdgesOfThisDirection - only edges of this direction are passed to the edgeMaker.

Throws:

IOException

readVertex

public Vertex readVertex(InputStream inputStream,
 Function<Attachable<Vertex>,Vertex> vertexAttachMethod)
                  throws IOException

Read a Vertex from output generated by any of the GraphSONWriter writeVertex or writeVertices methods or by GraphSONWriter.writeGraph(OutputStream, Graph).

Specified by:

readVertex in interface GraphReader

Parameters:

inputStream - a stream containing at least a single vertex as defined by the accompanying GraphWriter.writeVertex(OutputStream, Vertex).

vertexAttachMethod - a function that creates re-attaches a Vertex to a Host object.

Throws:

IOException

readVertex

public Vertex readVertex(InputStream inputStream,
 Function<Attachable<Vertex>,Vertex> vertexAttachMethod,
 Function<Attachable<Edge>,Edge> edgeAttachMethod,
 Direction attachEdgesOfThisDirection)
                  throws IOException

Read a Vertex from output generated by any of the GraphSONWriter writeVertex or writeVertices methods or by GraphSONWriter.writeGraph(OutputStream, Graph).

Specified by:

readVertex in interface GraphReader

Parameters:

inputStream - a stream containing at least one Vertex as defined by the accompanying GraphWriter.writeVertices(OutputStream, Iterator, Direction) method.

vertexAttachMethod - a function that creates re-attaches a Vertex to a Host object.

edgeAttachMethod - a function that creates re-attaches a Edge to a Host object.

attachEdgesOfThisDirection - only edges of this direction are passed to the edgeMaker.

Throws:

IOException

readEdge

public Edge readEdge(InputStream inputStream,
 Function<Attachable<Edge>,Edge> edgeAttachMethod)
              throws IOException

Read an Edge from output generated by GraphSONWriter.writeEdge(OutputStream, Edge) or via an Edge passed to GraphSONWriter.writeObject(OutputStream, Object).

Specified by:

readEdge in interface GraphReader

Parameters:

inputStream - a stream containing at least one Edge as defined by the accompanying GraphWriter.writeEdge(OutputStream, Edge) method.

edgeAttachMethod - a function that creates re-attaches a Edge to a Host object.

Throws:

IOException

readVertexProperty

public VertexProperty readVertexProperty(InputStream inputStream,
 Function<Attachable<VertexProperty>,VertexProperty> vertexPropertyAttachMethod)
                                  throws IOException

Read a VertexProperty from output generated by GraphSONWriter.writeVertexProperty(OutputStream, VertexProperty) or via an VertexProperty passed to GraphSONWriter.writeObject(OutputStream, Object).

Specified by:

readVertexProperty in interface GraphReader

Parameters:

inputStream - a stream containing at least one VertexProperty as written by the accompanying GraphWriter.writeVertexProperty(OutputStream, VertexProperty) method.

vertexPropertyAttachMethod - a function that creates re-attaches a VertexProperty to a Host object.

Returns:

the value returned by the attach method.

Throws:

IOException

readProperty

public Property readProperty(InputStream inputStream,
 Function<Attachable<Property>,Property> propertyAttachMethod)
                      throws IOException

Read a Property from output generated by GraphSONWriter.writeProperty(OutputStream, Property) or via an Property passed to GraphSONWriter.writeObject(OutputStream, Object).

Specified by:

readProperty in interface GraphReader

Parameters:

inputStream - a stream containing at least one Property as written by the accompanying GraphWriter.writeProperty(OutputStream, Property) method.

propertyAttachMethod - a function that creates re-attaches a Property to a Host object.

Returns:

the value returned by the attach method.

Throws:

IOException

readObject

public <C> C readObject(InputStream inputStream,
 Class<? extends C> clazz)
                 throws IOException

Reads an arbitrary object using the registered serializers.

Specified by:

readObject in interface GraphReader

Parameters:

inputStream - a stream containing an object.

clazz - the class expected to be in the stream - may or may not be used by the underlying implementation.

Throws:

IOException

build

public static GraphSONReader.Builder build()