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https://issues.apache.org/jira/browse/TINKERPOP-1750?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]
stephen mallette closed TINKERPOP-1750.
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Resolution: Won't Do
Will not merge per discussion on dev list:
https://lists.apache.org/thread.html/6af7b277ce435dcd71f8c921c276d96032f01a1fbe9b4cfdeaadc81d@%3Cdev.tinkerpop.apache.org%3E
This project has been released independent of TinkerPop and has been added to
the provider listings on the TinkerPop home page.
> An Object Graph Mapping Framework For Gremlin
> ---------------------------------------------
>
> Key: TINKERPOP-1750
> URL: https://issues.apache.org/jira/browse/TINKERPOP-1750
> Project: TinkerPop
> Issue Type: Improvement
> Components: structure, tinkergraph
> Affects Versions: 3.3.0
> Reporter: Karthick Sankarachary
>
> Here, we describe a framework that puts an object-oriented spin on the
> Gremlin property graph. It aims to make it much easier to specify business
> {{DSLs}} around Gremlin.
> h5. Object Model
> Every element in the property graph, whether it be a vertex (property) or an
> edge, is made up of properties, each of which is a {{String}} key and an
> arbitrary {{Java}} value. It only seems fitting then to try and represent
> that property as a strongly-typed {{Java}} field. The specific class in which
> that field is defined then becomes the vertex (property) or edge.
> Let's consider the example of the {{person}} vertex, taken from the
> {{TinkerFactory}}. In our object world, it would be defined as a {{Person}}
> class that extends a {{Vertex}} class like so:
> {code:java}
> @Data
> @Alias(label = "person")
> public class Person extends Vertex {
> public static ToVertex KnowsPeople = traversal -> traversal
> .out(Label.of(Knows.class))
> .hasLabel(Label.of(Person.class));
> @PrimaryKey
> private String name;
> @OrderingKey
> private int age;
> private Set<String> titles;
> private List<Location> locations;
> }
> {code}
> The person's {{name}} and {{age}} properties become primitive fields in the
> class. The {{KnowsPeople}} field in this class is an example of an in-line
> {{SubTraversal}}, which is just a reusable function that performs certain
> steps on a {{GraphTraversal}}.
> Its {{titles}} field, which is defined to be a {{Set}}, takes on the {{set}}
> cardinality. Similarly, the {{locations}} field gets the {{list}}
> cardinality. Since each {{location}} has it's own meta-properties, it
> deserves a {{Location}} class of it's own.
> {code:java}
> @Data
> public class Location extends Element {
> @OrderingKey
> @PropertyValue
> private String name;
> @OrderingKey
> private Instant startTime;
> private Instant endTime;
> }
> {code}
> The value of the {{location}} is stored in {{name}}, due to the placement of
> the {{@PropertyValue}} annotation. Every other field in that class becomes
> the {{location's}} meta-property.
> h5. Updating Objects
> The {{Graph}} interface lets you update the graph using {{Vertex}} or
> {{Edge}} objects. Below, a {{person}} vertex containing a list of
> {{locations}} is added, along with three outgoing edges.
> {code:java}
> graph
> .addVertex(
> Person.of("marko",
> Location.of("san diego", 1997, 2001),
> Location.of("santa cruz", 2001, 2004),
> Location.of("brussels", 2004, 2005),
> Location.of("santa fe", 2005))).as("marko")
> .addEdge(Develops.of(2010), "tinkergraph")
> .addEdge(Uses.of(Proficient), "gremlin")
> .addEdge(Uses.of(Expert), "tinkergraph")
> {code}
> Since the object being added may already exist in the graph, we provide
> various ways to resolve "merge conflicts", such as {{MERGE}}, {{REPLACE}},
> {{CREATE}}, {{IGNORE}} and {{INSERT}}.
> h5. Querying Objects
> Next, let's see how to use the {{Query}} interface. The following snippet
> queries the graph by a chain of {{SubTraversals}}, and parses the result into
> a list of {{Person}} vertices.
> {code:java}
> List<Person> friends = query
> .by(HasKeys.of(modern.marko), Person.KnowsPeople)
> .list(Person.class);
> {code}
> Below, we query by an {{AnyTraversal}} (a function on the
> {{GraphTraversalSource}}), and get a single {{Person}} back.
> {code:java}
> Person marko = Person.of("marko");
> Person actual = query
> .by(g -> g.V().hasLabel(marko.label()).has("name", marko.name()))
> .one(Person.class);
> {code}
> h5. Service Provider Interface
> To become a {{gremlin-objects}} provider, you would need to implement the
> {{GraphSystem}}, which supplies a {{GraphTraversalSource}}. And then, extend
> the {{ObjectGraph}} and {{ObjectQuery}} abstract classes, constructor
> injecting your {{GraphSystem}}.
> For more details, please see the [readme
> file|https://github.com/karthicks/tinkerpop/blob/e9b1ac506900008dd52d12754c75ecf3ddbef01c/gremlin-objects/README.asciidoc]
> in the the pull request that I'm about to submit, which also comes with a
> reference implementation based on {{TinkerGraph}}. While I also have a
> {{DataStax}} implementation, which we use at Elementum, a supply chain graph
> company, it isn't included since it depends on an older TinkerPop version.
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