How do I resolve an "Unchecked assignment" warning in my query code?

[Tim Stewart]

My pom.xml file:

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>

    <groupId>com.example</groupId>
    <artifactId>tinkerpop3-type-confusion</artifactId>
    <version>1.0-SNAPSHOT</version>


    <dependencies>
        <dependency>
            <groupId>org.apache.tinkerpop</groupId>
            <artifactId>gremlin-core</artifactId>
            <version>3.0.2-incubating</version>
        </dependency>

        <dependency>
            <groupId>com.thinkaurelius.titan</groupId>
            <artifactId>titan-cassandra</artifactId>
            <version>1.0.0</version>
        </dependency>

    </dependencies>

</project>

My one and only source file:

import com.thinkaurelius.titan.core.TitanFactory;
import com.thinkaurelius.titan.core.TitanGraph;
import com.thinkaurelius.titan.core.TitanVertex;
import org.apache.commons.configuration.BaseConfiguration;

public class Main
{
    public static void main(String[] args)
    {
        final BaseConfiguration config = new BaseConfiguration();

        config.setProperty("schema.default", "none");
        config.setProperty("storage.backend","inmemory");
        config.setProperty("cache.db-cache", Boolean.TRUE);

        final TitanGraph graph = TitanFactory.open(config);

        Iterable<TitanVertex> vertices = graph.query().has("name", "tim").vertices();
    }

} 

 

My IDE (IntelliJ v15) tells me:

Unchecked assignment: 'java.lang.Iterable' to 'java.lang.Iterable'. Reason: 'graph.query().has("name", "tim")' has raw type, so result of vertices is erased 

on this line:

 Iterable<TitanVertex> vertices = graph.query().has("name", "tim").vertices();

The recommended fix is to replace Iterable<TitanVertex> with Iterable but I don't want to use raw types if I don't have to.

Any ideas on how I can avoid raw types and eliminate (without ignoring) this warning?

Thanks!

Tim

[Stephen Mallette]

Hi Tim, if you're on Titan 1.0, I don't think there's a need to use the Titan API for queries.  Your code should be more like:

final TitanGraph graph = TitanFactory.open(config);

final GraphTraversalSource g = graph.traversal()

final Iterator<Vertex> vertices = g.V().has("name", "tim");

That works for me without type erasure issues.  I know that doesn't answer your question exactly but I'm not sure what the answer is there offhand. 

--
You received this message because you are subscribed to the Google Groups "Gremlin-users" group.
To unsubscribe from this group and stop receiving emails from it, send an email to gremlin-user...@googlegroups.com.
To view this discussion on the web visit https://groups.google.com/d/msgid/gremlin-users/8dcd8082-4df6-47a3-82a9-592a71663bc6%40googlegroups.com.
For more options, visit https://groups.google.com/d/optout.

[Tim Stewart]

Thanks Stephen!  That worked great for my query that started from a TitanGraph.  Is there a similar approach for when your search starts with a TitanVertex?

E.g. 

TitanVertex v = ....;

Iterator<TitanVertex> i = v.query()

                           .direction(Direction.OUT)

                           .labels(Schema.HAS_PET)

                           .vertices()

                           .iterator();

[Stephen Mallette]

you can't start traversals from Graph elements anymore. you need to pass them back into the Traversal as in:

g.V(v).out('hasPet")

To view this discussion on the web visit https://groups.google.com/d/msgid/gremlin-users/ac7cd0ff-041c-495e-8bd0-2aeb78fde503%40googlegroups.com.

[Tim Stewart]

Thanks!