// Get the edges from a mesh feature
public static EdgeCollection getEdgesFromMeshFeature(Feature feature)
{
    // Check if the feature is a mesh feature
    if (feature.getGeometryType() == GeometryType.MESH)   
    {
        // Get the MeshGeometry form the feature and return the edges from it
        return feature.getGeometryAsMesh().getEdges();
    }

    // The Feature is not a Mesh, so return nothing
    return null;
}