software.amazon.neptune.cluster.CommonClusterEndpointsFetchStrategy Maven / Gradle / Ivy

Go to download

Show more of this group Show more artifacts with this name
Show all versions of gremlin-client Show documentation

A Java Gremlin client for Amazon Neptune that allows you to change the endpoints used by the client as it is running.

There is a newer version: 2.1.0

/*
Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
Licensed under the Apache License, Version 2.0 (the "License").
You may not use this file except in compliance with the License.
A copy of the License is located at
    http://www.apache.org/licenses/LICENSE-2.0
or in the "license" file accompanying this file. This file is distributed
on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either
express or implied. See the License for the specific language governing
permissions and limitations under the License.
*/

package software.amazon.neptune.cluster;

import org.apache.tinkerpop.gremlin.driver.EndpointCollection;

import java.util.Collection;
import java.util.HashMap;
import java.util.Map;

class CommonClusterEndpointsFetchStrategy implements ClusterEndpointsFetchStrategy {

    private final ClusterMetadataSupplier clusterMetadataSupplier;

    CommonClusterEndpointsFetchStrategy(ClusterMetadataSupplier clusterMetadataSupplier) {
        this.clusterMetadataSupplier = clusterMetadataSupplier;
    }

    @Override
    public ClusterMetadataSupplier clusterMetadataSupplier() {
        return clusterMetadataSupplier;
    }

    @Override
    public Map getEndpoints(Collection selectors, boolean refresh) {
        if (refresh) {
            return refreshEndpoints(selectors);
        }

        NeptuneClusterMetadata clusterMetadata = clusterMetadataSupplier().getClusterMetadata();

        if (clusterMetadata == null) {
            return refreshEndpoints(selectors);
        }

        Map results = new HashMap<>();

        for (EndpointsSelector selector : selectors) {
            results.put(selector, clusterMetadata.select(selector));
        }

        return results;
    }

    private Map refreshEndpoints(Collection selectors) {
        NeptuneClusterMetadata clusterMetadata = clusterMetadataSupplier.refreshClusterMetadata();

        Map results = new HashMap<>();

        for (EndpointsSelector selector : selectors) {
            results.put(selector, clusterMetadata.select(selector));
        }

        return results;
    }
}