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package org.apache.kafka.streams;


/**
 * Represents all the query options that a user can provide to state what kind of stores it is expecting. The options would be whether a user would want to enable/disable stale stores* or whether it knows the list of partitions that it specifically wants to fetch. If this information is not provided the default behavior is to fetch the stores for all the partitions available on that instance* for that particular store name.
 * It contains a partition, which for a point queries can be populated from the  KeyQueryMetadata.
 */
public class StoreQueryParams<T> {

    private Integer partition;
    private boolean includeStaleStores;
    private final String storeName;
    private final QueryableStoreType<T> queryableStoreType;

    private StoreQueryParams(final String storeName, final QueryableStoreType<T>  queryableStoreType) {
        this.storeName = storeName;
        this.queryableStoreType = queryableStoreType;
    }

    public static <T> StoreQueryParams<T> fromNameAndType(final String storeName, final QueryableStoreType<T>  queryableStoreType) {
        return new StoreQueryParams<T> StoreQueryParams<T>(storeName, queryableStoreType);
    }

    /**
     * Get the partition to be used to fetch list of Queryable store from QueryableStoreProvider.
     * If the function returns null, it would mean that no specific partition has been requested so all the local partitions
     * for the store will be returned.
     *
     * @return Integer partition
     */
    public Integer getPartition() {
        return partition;
    }

    /**
     * Get the flag includeStaleStores. If true, include standbys and recovering stores along with running stores.
     *
     * @return boolean includeStaleStores
     */
    public boolean includeStaleStores() {
        return includeStaleStores;
    }

    /**
     * Get the {@link StoreQueryParams} with stale(standby, restoring) stores added via fetching the stores.
     *
     * @param partition   The specific integer partition to be fetched from the stores list by using {@link StoreQueryParams}.
     *
     * @return String storeName
     */
    public StoreQueryParams<T> withPartition(final Integer partition) {
        this.partition = partition;
        return this;
    }

    /**
     * Get the {@link StoreQueryParams} with stale(standby, restoring) stores added via fetching the stores.
     *
     * @return String storeName
     */
    public StoreQueryParams<T> withIncludeStaleStores() {
        this.includeStaleStores = true;
        return this;
    }

    /**
     * Get the store name for which key is queried by the user.
     *
     * @return String storeName
     */
    public String storeName() {
        return storeName;
    }

    /**
     * Get the queryable store type for which key is queried by the user.
     *
     * @return QueryableStoreType queryableStoreType
     */
    public QueryableStoreType<T> queryableStoreType() {
        return queryableStoreType;
    }
}