EmptyGraph (Apache TinkerPop 3.4.4-SNAPSHOT API)

java.lang.Object
- org.apache.tinkerpop.gremlin.structure.util.empty.EmptyGraph

All Implemented Interfaces:

AutoCloseable, Graph, Host
```
public final class EmptyGraph
extends Object
implements Graph
```
Author:

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

Nested Class Summary

Nested Classes
Modifier and Type	Class and Description
`static class`	`EmptyGraph.EmptyGraphFactory` `EmptyGraph` doesn't have a standard `open()` method because it is a singleton.
`static class`	`EmptyGraph.EmptyGraphFeatures` Features defined such that they support immutability but allow all other possibilities.

Nested classes/interfaces inherited from interface org.apache.tinkerpop.gremlin.structure.Graph
Graph.Exceptions, Graph.Features, Graph.Hidden, Graph.OptIn, Graph.OptIns, Graph.OptOut, Graph.OptOuts, Graph.Variables

Field Summary
- Fields inherited from interface org.apache.tinkerpop.gremlin.structure.Graph
  GRAPH

Method Summary

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`Vertex`	`addVertex(Object... keyValues)` Add a `Vertex` to the graph given an optional series of key/value pairs.
`void`	`close()` Closing a `Graph` is equivalent to "shutdown" and implies that no further operations can be executed on the instance.
`GraphComputer`	`compute()` Generate a `GraphComputer` using the default engine of the underlying graph system.
`<C extends GraphComputer> C`	`compute(Class<C> graphComputerClass)` Declare the `GraphComputer` to use for OLAP operations on the graph.
`Configuration`	`configuration()` Get the `org.apache.commons.configuration.Configuration` associated with the construction of this graph.
`Iterator<Edge>`	`edges(Object... edgeIds)` Get the `Edge` objects in this graph with the provided edge ids or `Edge` objects.
`Graph.Features`	`features()` Gets the `Graph.Features` exposed by the underlying `Graph` implementation.
`static Graph`	`instance()`
`String`	`toString()`
`Transaction`	`tx()` Configure and control the transactions for those graphs that support this feature.
`Graph.Variables`	`variables()` A collection of global `Graph.Variables` associated with the graph.
`Iterator<Vertex>`	`vertices(Object... vertexIds)` Get the `Vertex` objects in this graph with the provided vertex ids or `Vertex` objects themselves.

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Methods inherited from interface org.apache.tinkerpop.gremlin.structure.Graph
addVertex, io, traversal, traversal

Methods inherited from interface org.apache.tinkerpop.gremlin.structure.util.Host
getHostingVertex

- Method Detail
  - instance
```
public static Graph instance()
```
  - features
```
public Graph.Features features()
```
    Description copied from interface: Graph
    
    Gets the Graph.Features exposed by the underlying Graph implementation.
    
    Specified by:
    
    features in interface Graph
  - addVertex
```
public Vertex addVertex(Object... keyValues)
```
    Description copied from interface: Graph
    
    Add a Vertex to the graph given an optional series of key/value pairs. These key/values must be provided in an even number where the odd numbered arguments are String property keys and the even numbered arguments are the related property values.
    
    Specified by:
    
    addVertex in interface Graph
    
    Parameters:
    
    keyValues - The key/value pairs to turn into vertex properties
    
    Returns:
    
    The newly created vertex
  - compute
```
public <C extends GraphComputer> C compute(Class<C> graphComputerClass)
```
    Description copied from interface: Graph
    
    Declare the GraphComputer to use for OLAP operations on the graph. If the graph does not support graph computer then an UnsupportedOperationException is thrown.
    
    Specified by:
    
    compute in interface Graph
    
    Parameters:
    
    graphComputerClass - The graph computer class to use.
    
    Returns:
    
    A graph computer for processing this graph
  - compute
```
public GraphComputer compute()
```
    Description copied from interface: Graph
    
    Generate a GraphComputer using the default engine of the underlying graph system. This is a shorthand method for the more involved method that uses Graph.compute(Class).
    
    Specified by:
    
    compute in interface Graph
    
    Returns:
    
    A default graph computer
  - tx
```
public Transaction tx()
```
    Description copied from interface: Graph
    
    Configure and control the transactions for those graphs that support this feature. Note that this method does not indicate the creation of a "transaction" object. A Transaction in the TinkerPop context is a transaction "factory" or "controller" that helps manage transactions owned by the underlying graph database.
    
    Specified by:
    
    tx in interface Graph
  - variables
```
public Graph.Variables variables()
```
    Description copied from interface: Graph
    
    A collection of global Graph.Variables associated with the graph. Variables are used for storing metadata about the graph.
    
    Specified by:
    
    variables in interface Graph
    
    Returns:
    
    The variables associated with this graph
  - configuration
```
public Configuration configuration()
```
    Description copied from interface: Graph
    
    Get the org.apache.commons.configuration.Configuration associated with the construction of this graph. Whatever configuration was passed to GraphFactory#open(org.apache.commons.configuration.Configuration) is what should be returned by this method.
    
    Specified by:
    
    configuration in interface Graph
    
    Returns:
    
    the configuration used during graph construction.
  - close
```
public void close()
           throws Exception
```
    Description copied from interface: Graph
    
    Closing a Graph is equivalent to "shutdown" and implies that no further operations can be executed on the instance. Users should consult the documentation of the underlying graph database implementation for what this "shutdown" will mean in general and, if supported, how open transactions are handled. It will typically be the end user's responsibility to synchronize the thread that calls close() with other threads that are accessing open transactions. In other words, be sure that all work performed on the Graph instance is complete prior to calling this method.
    TinkerPop does not enforce any particular semantics with respect to "shutdown". It is up to the graph provider to decide what this method will do.
    
    Specified by:
    
    close in interface AutoCloseable
    
    Specified by:
    
    close in interface Graph
    
    Throws:
    
    Exception
  - vertices
```
public Iterator<Vertex> vertices(Object... vertexIds)
```
    Description copied from interface: Graph
    Get the Vertex objects in this graph with the provided vertex ids or Vertex objects themselves. If no ids are provided, get all vertices. Note that a vertex identifier does not need to correspond to the actual id used in the graph. It needs to be a bit more flexible than that in that given the Graph.Features around id support, multiple arguments might be applicable here.
    If the graph return true for Graph.Features.ElementFeatures.supportsNumericIds() then it should support filters as with:
    - g.vertices(v)
    - g.vertices(v.id())
    - g.vertices(1)
    - g.vertices(1L)
    - g.vertices(1.0d)
    - g.vertices(1.0f)
    - g.vertices("1")
    If the graph return true for Graph.Features.ElementFeatures.supportsCustomIds() ()} then it should support filters as with:
    - g.vertices(v)
    - g.vertices(v.id())
    - g.vertices(v.id().toString())
    If the graph return true for Graph.Features.ElementFeatures.supportsAnyIds() ()} then it should support filters as with:
    - g.vertices(v)
    - g.vertices(v.id())
    If the graph return true for Graph.Features.ElementFeatures.supportsStringIds() ()} then it should support filters as with:
    - g.vertices(v)
    - g.vertices(v.id().toString())
    - g.vertices("id")
    If the graph return true for Graph.Features.ElementFeatures.supportsStringIds() ()} then it should support filters as with:
    - g.vertices(v)
    - g.vertices(v.id().toString())
    - g.vertices("id")
    Specified by:
    
    vertices in interface Graph
    
    Parameters:
    
    vertexIds - the ids of the vertices to get
    
    Returns:
    
    an Iterator of vertices that match the provided vertex ids
  - edges
```
public Iterator<Edge> edges(Object... edgeIds)
```
    Description copied from interface: Graph
    Get the Edge objects in this graph with the provided edge ids or Edge objects. If no ids are provided, get all edges. Note that an edge identifier does not need to correspond to the actual id used in the graph. It needs to be a bit more flexible than that in that given the Graph.Features around id support, multiple arguments might be applicable here.
    If the graph return true for Graph.Features.ElementFeatures.supportsNumericIds() then it should support filters as with:
    - g.edges(e)
    - g.edges(e.id())
    - g.edges(1)
    - g.edges(1L)
    - g.edges(1.0d)
    - g.edges(1.0f)
    - g.edges("1")
    If the graph return true for Graph.Features.ElementFeatures.supportsCustomIds() ()} then it should support filters as with:
    - g.edges(e)
    - g.edges(e.id())
    - g.edges(e.id().toString())
    If the graph return true for Graph.Features.ElementFeatures.supportsAnyIds() ()} then it should support filters as with:
    - g.edges(e)
    - g.edges(e.id())
    If the graph return true for Graph.Features.ElementFeatures.supportsStringIds() ()} then it should support filters as with:
    - g.edges(e)
    - g.edges(e.id().toString())
    - g.edges("id")
    Specified by:
    
    edges in interface Graph
    
    Parameters:
    
    edgeIds - the ids of the edges to get
    
    Returns:
    
    an Iterator of edges that match the provided edge ids
  - toString
```
public String toString()
```
    Overrides:
    
    toString in class Object

Class EmptyGraph

Nested Class Summary

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

Field Summary

Fields inherited from interface org.apache.tinkerpop.gremlin.structure.Graph

Method Summary

Methods inherited from class java.lang.Object

Methods inherited from interface org.apache.tinkerpop.gremlin.structure.Graph

Methods inherited from interface org.apache.tinkerpop.gremlin.structure.util.Host

Method Detail

instance

features

addVertex

compute

compute

tx

variables

configuration

close

vertices

edges

toString