com.basho.riak.client.api.commands.indexes.KeyIndexQuery Maven / Gradle / Ivy

Go to download
Show more of this group Show more artifacts with this name
Show all versions of riak-client Show documentation
HttpClient-based client for Riak
The newest version!
package com.basho.riak.client.api.commands.indexes;

import com.basho.riak.client.core.operations.SecondaryIndexQueryOperation;
import com.basho.riak.client.core.query.Namespace;
import com.basho.riak.client.core.query.indexes.IndexNames;
import com.basho.riak.client.core.util.BinaryValue;
import com.basho.riak.client.core.util.DefaultCharset;

/**
 * Performs a 2i query across the special $key index, for a known bucket & range of keys,
 * and returns the keys within that range in that bucket.
 * 
 * 
 * A KeyIndexQuery is used when you want to fetch a range of keys for a bucket. A namespace and a key range is needed.
 * 
 *  * {@code
 * Namespace ns = new Namespace("my_type", "my_bucket");
 * KeyIndexQuery q = new KeyIndexQuery.Builder(ns, "foo10", "foo19").build();
 * RawIndexquery.Response resp = client.execute(q);}
 *
 * 
 * You can also stream the results back before the operation is fully complete.
 * This reduces the time between executing the operation and seeing a result,
 * and reduces overall memory usage if the iterator is consumed quickly enough.
 * The result iterable can only be iterated once though.
 * If the thread is interrupted while the iterator is polling for more results,
 * a {@link RuntimeException} will be thrown.
 * 
 * {@code
 * Namespace ns = new Namespace("my_type", "my_bucket");
 * KeyIndexQuery q = new KeyIndexQuery.Builder(ns, "foo10", "foo19").build();
 * RiakFuture streamingFuture =
 *     client.executeAsyncStreaming(q, 200);
 * RawIndexQuery.StreamingResponse streamingResponse = streamingFuture.get();
 *
 * for (BinIndexQuery.Response.Entry e : streamingResponse)
 * {
 *     System.out.println(e.getRiakObjectLocation().getKeyAsString());
 * }
 * // Wait for the command to fully finish.
 * streamingFuture.await();
 * // The StreamingResponse will also contain the continuation, if the operation returned one.
 * streamingResponse.getContinuation(); }
 * 
 *
 * @author Alex Moore 
 * @since 2.0.7
 */
public class KeyIndexQuery extends RawIndexQuery
{
    private KeyIndexQuery(Init builder)
    {
        super(builder);
    }

    public static class Builder extends Init
    {
        public Builder(Namespace namespace, String start, String end)
        {
            this(namespace,
                 BinaryValue.unsafeCreate(start.getBytes(DefaultCharset.get())),
                 BinaryValue.unsafeCreate(end.getBytes(DefaultCharset.get())));
        }

        public Builder(Namespace namespace, BinaryValue start, BinaryValue end)
        {
            super(namespace, IndexNames.KEY, start, end);
        }

        @Override
        protected Builder self()
        {
            return this;
        }

        public KeyIndexQuery build()
        {
            return new KeyIndexQuery(this);
        }
    }
}