```
public interface GraphComputer
```
The GraphComputer is responsible for the execution of a VertexProgram and then a set of MapReduce jobs over the vertices in the Graph. It is up to the GraphComputer implementation to determine the appropriate memory structures given the computing substrate.

Author:

Marko A. Rodriguez (http://markorodriguez.com), Matthias Broecheler (me@matthiasb.com)

Nested Class Summary

Nested Classes
Modifier and Type	Interface	Description
`static class`	`GraphComputer.Exceptions`
`static interface`	`GraphComputer.Features`
`static class`	`GraphComputer.Persist`
`static class`	`GraphComputer.ResultGraph`

Method Summary

All Methods Instance Methods Abstract Methods Default Methods
Modifier and Type	Method	Description
`default GraphComputer`	`configure(String key, Object value)`	Set an arbitrary configuration key/value for the underlying `Configuration` in the `GraphComputer`.
`GraphComputer`	`edges(Traversal<Vertex,Edge> edgeFilter)`	Add a filter that will limit which edges of the vertices are loaded from the graph source.
`default GraphComputer.Features`	`features()`
`GraphComputer`	`mapReduce(MapReduce mapReduce)`	Add a `MapReduce` job to the set of MapReduce jobs to be executed by the `GraphComputer`.
`GraphComputer`	`persist(GraphComputer.Persist persist)`	Set the `GraphComputer.Persist` level of the computation.
`GraphComputer`	`program(VertexProgram vertexProgram)`	Set the `VertexProgram` to be executed by the `GraphComputer`.
`GraphComputer`	`result(GraphComputer.ResultGraph resultGraph)`	Set the `GraphComputer.ResultGraph` of the computation.
`Future<ComputerResult>`	`submit()`	Submit the `VertexProgram` and the set of `MapReduce` jobs for execution by the `GraphComputer`.
`GraphComputer`	`vertices(Traversal<Vertex,Vertex> vertexFilter)`	Add a filter that will limit which vertices are loaded from the graph source.
`GraphComputer`	`workers(int workers)`	Set the desired number of workers to execute the `VertexProgram` and `MapReduce` jobs.

- Method Detail
  - result
```
GraphComputer result(GraphComputer.ResultGraph resultGraph)
```
    Set the GraphComputer.ResultGraph of the computation. If this is not set explicitly by the user, then the VertexProgram can choose the most efficient result for its intended use. If there is no declared vertex program, then the GraphComputer defaults to GraphComputer.ResultGraph.ORIGINAL.
    
    Parameters:
    
    resultGraph - the type of graph to be returned by ComputerResult.graph()
    
    Returns:
    
    the updated GraphComputer with newly set result graph
  - persist
```
GraphComputer persist(GraphComputer.Persist persist)
```
    Set the GraphComputer.Persist level of the computation. If this is not set explicitly by the user, then the\ VertexProgram can choose the most efficient persist for the its intended use. If there is no declared vertex program, then the GraphComputer defaults to GraphComputer.Persist.NOTHING.
    
    Parameters:
    
    persist - the persistence level of the resultant computation
    
    Returns:
    
    the updated GraphComputer with newly set persist
  - program
```
GraphComputer program(VertexProgram vertexProgram)
```
    Set the VertexProgram to be executed by the GraphComputer. There can only be one VertexProgram for the GraphComputer.
    
    Parameters:
    
    vertexProgram - the VertexProgram to be executed
    
    Returns:
    
    the updated GraphComputer with newly set VertexProgram
  - mapReduce
```
GraphComputer mapReduce(MapReduce mapReduce)
```
    Add a MapReduce job to the set of MapReduce jobs to be executed by the GraphComputer. There can be any number of MapReduce jobs.
    
    Parameters:
    
    mapReduce - the MapReduce job to add to the computation
    
    Returns:
    
    the updated GraphComputer with newly added MapReduce job
  - workers
```
GraphComputer workers(int workers)
```
    Set the desired number of workers to execute the VertexProgram and MapReduce jobs. This is a recommendation to the underlying GraphComputer implementation and is allowed to deviate accordingly by the implementation.
    
    Parameters:
    
    workers - the number of workers to execute the submission
    
    Returns:
    
    the updated GraphComputer with newly set worker count
  - vertices
```
GraphComputer vertices(Traversal<Vertex,Vertex> vertexFilter)
                throws IllegalArgumentException
```
    Add a filter that will limit which vertices are loaded from the graph source. The provided Traversal can only check the vertex, its vertex properties, and the vertex property properties. The loaded graph will only have those vertices that pass through the provided filter.
    
    Parameters:
    
    vertexFilter - the traversal to verify whether or not to load the current vertex
    
    Returns:
    
    the updated GraphComputer with newly set vertex filter
    
    Throws:
    
    IllegalArgumentException - if the provided traversal attempts to access vertex edges
  - edges
```
GraphComputer edges(Traversal<Vertex,Edge> edgeFilter)
             throws IllegalArgumentException
```
    Add a filter that will limit which edges of the vertices are loaded from the graph source. The provided Traversal can only check the local star graph of the vertex and thus, can not access properties/labels of the adjacent vertices. The vertices of the loaded graph will only have those edges that pass through the provided filter.
    
    Parameters:
    
    edgeFilter - the traversal that determines which edges are loaded for each vertex
    
    Returns:
    
    the updated GraphComputer with newly set edge filter
    
    Throws:
    
    IllegalArgumentException - if the provided traversal attempts to access adjacent vertices
  - configure
```
default GraphComputer configure(String key,
                                Object value)
```
    Set an arbitrary configuration key/value for the underlying Configuration in the GraphComputer. Typically, the other fluent methods in GraphComputer should be used to configure the computation. However, for some custom configuration in the underlying engine, this method should be used. Different GraphComputer implementations will have different key/values and thus, parameters placed here are generally not universal to all GraphComputer implementations. The default implementation simply does nothing and returns the GraphComputer unchanged.
    
    Parameters:
    
    key - the key of the configuration
    
    value - the value of the configuration
    
    Returns:
    
    the updated GraphComputer with newly set key/value configuration
  - submit
```
Future<ComputerResult> submit()
```
    Submit the VertexProgram and the set of MapReduce jobs for execution by the GraphComputer.
    
    Returns:
    
    a Future denoting a reference to the asynchronous computation and where to get the DefaultComputerResult when its is complete.
  - features
```
default GraphComputer.Features features()
```

Interface GraphComputer

Nested Class Summary

Method Summary

Method Detail

result

persist

program

mapReduce

workers

vertices

edges

configure

submit

features