UnorderedDistinctMap.java

// Copyright (c) Microsoft Corporation. All rights reserved.
// Licensed under the MIT License.
package com.azure.cosmos.implementation.query;

import com.azure.cosmos.implementation.Resource;
import com.azure.cosmos.implementation.Utils;
import com.azure.cosmos.implementation.routing.UInt128;

import java.io.IOException;
import java.util.Collections;
import java.util.Set;
import java.util.concurrent.ConcurrentHashMap;

public class UnorderedDistinctMap extends DistinctMap {
    // This is intended to be used as a concurrent hash set only
    private final Set<UInt128> resultSet;

    public UnorderedDistinctMap() {
        resultSet = Collections.newSetFromMap(new ConcurrentHashMap<>());
    }

    @Override
    public boolean add(Object resource, Utils.ValueHolder<UInt128> outHash) {
        try {
            if (resource instanceof Resource) {
                // We do this to ensure the property order in document should not effect the hash
                resource = getSortedJsonStringValueFromResource((Resource)resource);
            }
            outHash.v = DistinctHash.getHash(resource);
            return resultSet.add(outHash.v);
        } catch (IOException e) {
            throw new IllegalStateException("Failed to add value to distinct map", e);
        }
    }
}