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

Class GryoReader

java.lang.Object

org.apache.tinkerpop.gremlin.structure.io.gryo.GryoReader

All Implemented Interfaces:

GraphReader

public final class GryoReader
extends Object
implements GraphReader

The GraphReader for the Gremlin Structure serialization format based on Kryo. The format is meant to be non-lossy in terms of Gremlin Structure to Gremlin Structure migrations (assuming both structure implementations support the same graph features).

This implementation is not thread-safe. Have one GryoReader instance per thread.

Author:

Stephen Mallette (http://stephen.genoprime.com), Marko A. Rodriguez (http://markorodriguez.com)

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static final class	GryoReader.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 GryoReader.Builder	build()
Edge	readEdge(InputStream inputStream, Function<Attachable<Edge>,Edge> edgeAttachMethod)	Read an Edge from output generated by GryoWriter.writeEdge(OutputStream, Edge) or via an Edge passed to GryoWriter.writeObject(OutputStream, Object).
void	readGraph(InputStream inputStream, Graph graphToWriteTo)	Read data into a Graph from output generated by any of the GryoWriter 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 GryoWriter.writeProperty(OutputStream, Property) or via an Property passed to GryoWriter.writeObject(OutputStream, Object).
Vertex	readVertex(InputStream inputStream, Function<Attachable<Vertex>,Vertex> vertexAttachMethod)	Read a Vertex from output generated by any of the GryoWriter writeVertex or writeVertices methods or by GryoWriter.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 GryoWriter writeVertex or writeVertices methods or by GryoWriter.writeGraph(OutputStream, Graph).
Optional<Vertex>	readVertex(InputStream inputStream, GraphFilter graphFilter)	Reads a single vertex from an InputStream.
VertexProperty	readVertexProperty(InputStream inputStream, Function<Attachable<VertexProperty>,VertexProperty> vertexPropertyAttachMethod)	Read a VertexProperty from output generated by GryoWriter.writeVertexProperty(OutputStream, VertexProperty) or via an VertexProperty passed to GryoWriter.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 GryoWriter writeVertex or writeVertices methods or by GryoWriter.writeGraph(OutputStream, Graph).

Methods inherited from class java.lang.Object

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

Method Details

readGraph

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

Read data into a Graph from output generated by any of the GryoWriter 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 GraphWriter.writeGraph(OutputStream, Graph).

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

Throws:

IOException

readVertex

public Optional<Vertex> readVertex(InputStream inputStream,
 GraphFilter graphFilter)
                            throws IOException

Description copied from interface: GraphReader

Reads a single vertex from an InputStream. This method will filter the read the read vertex by the provided GraphFilter. If the graph filter will filter the vertex itself, then the returned Optional is empty.

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).

graphFilter - The GraphFilter to filter the vertex and its associated edges by.

Returns:

the vertex with filtered edges or Optional.empty() if the vertex itself was filtered.

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 GryoWriter writeVertex or writeVertices methods or by GryoWriter.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 GryoWriter writeVertex or writeVertices methods or by GryoWriter.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 GryoWriter writeVertex or writeVertices methods or by GryoWriter.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 GryoWriter.writeEdge(OutputStream, Edge) or via an Edge passed to GryoWriter.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 GryoWriter.writeVertexProperty(OutputStream, VertexProperty) or via an VertexProperty passed to GryoWriter.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 GryoWriter.writeProperty(OutputStream, Property) or via an Property passed to GryoWriter.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 GryoReader.Builder build()