graphdb/src/main/java/com/tinkerpop/blueprints/impls/orient/OrientBaseGraph.java
public OrientEdgeType createEdgeType(final String iClassName, final int clusters) {
    makeActive();
    return createEdgeType(iClassName, (String) null, clusters);
  }
public OrientEdgeType createEdgeType(final String iClassName, final int clusters) {
    makeActive();
    return createEdgeType(iClassName, (String) null, clusters);
  }
Creates a new Edge persistent class.

@param iClassName Edge class name
@param clusters   The number of clusters to create for the new class. By default the MINIMUMCLUSTERS database setting is used.
In v2.2 and later, the number of clusters are proportioned to the amount of cores found on the machine

@return OrientEdgeType instance representing the persistent class