com.hazelcast.client.map.impl.ClientMapPartitionIterator Maven / Gradle / Ivy
/*
* Copyright (c) 2008-2020, Hazelcast, Inc. 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.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License 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 com.hazelcast.client.map.impl;
import com.hazelcast.client.impl.clientside.HazelcastClientInstanceImpl;
import com.hazelcast.client.impl.protocol.ClientMessage;
import com.hazelcast.client.impl.protocol.codec.MapFetchEntriesCodec;
import com.hazelcast.client.impl.protocol.codec.MapFetchKeysCodec;
import com.hazelcast.client.proxy.ClientMapProxy;
import com.hazelcast.client.spi.ClientContext;
import com.hazelcast.client.spi.impl.ClientInvocation;
import com.hazelcast.client.spi.impl.ClientInvocationFuture;
import com.hazelcast.core.IMap;
import com.hazelcast.map.impl.iterator.AbstractMapPartitionIterator;
import com.hazelcast.spi.serialization.SerializationService;
import com.hazelcast.util.ExceptionUtil;
import java.util.List;
/**
* Iterator for iterating map entries in the {@code partitionId}. The values are not fetched one-by-one but rather in batches.
* NOTE
* Iterating the map should be done only when the {@link IMap} is not being
* mutated and the cluster is stable (there are no migrations or membership changes).
* In other cases, the iterator may not return some entries or may return an entry twice.
*/
public class ClientMapPartitionIterator extends AbstractMapPartitionIterator {
private final ClientMapProxy mapProxy;
private final ClientContext context;
public ClientMapPartitionIterator(ClientMapProxy mapProxy, ClientContext context, int fetchSize,
int partitionId, boolean prefetchValues) {
super(mapProxy, fetchSize, partitionId, prefetchValues);
this.mapProxy = mapProxy;
this.context = context;
}
@Override
protected List fetch() {
HazelcastClientInstanceImpl client = (HazelcastClientInstanceImpl) context.getHazelcastInstance();
if (prefetchValues) {
return fetchWithPrefetchValues(client);
} else {
return fetchWithoutPrefetchValues(client);
}
}
private List fetchWithoutPrefetchValues(HazelcastClientInstanceImpl client) {
ClientMessage request = MapFetchKeysCodec.encodeRequest(mapProxy.getName(), partitionId,
lastTableIndex, fetchSize);
ClientInvocation clientInvocation = new ClientInvocation(client, request, mapProxy.getName(), partitionId);
try {
ClientInvocationFuture f = clientInvocation.invoke();
MapFetchKeysCodec.ResponseParameters responseParameters = MapFetchKeysCodec.decodeResponse(f.get());
setLastTableIndex(responseParameters.keys, responseParameters.tableIndex);
return responseParameters.keys;
} catch (Exception e) {
throw ExceptionUtil.rethrow(e);
}
}
private List fetchWithPrefetchValues(HazelcastClientInstanceImpl client) {
ClientMessage request = MapFetchEntriesCodec.encodeRequest(mapProxy.getName(), partitionId, lastTableIndex,
fetchSize);
ClientInvocation clientInvocation = new ClientInvocation(client, request, mapProxy.getName(), partitionId);
try {
ClientInvocationFuture f = clientInvocation.invoke();
MapFetchEntriesCodec.ResponseParameters responseParameters = MapFetchEntriesCodec.decodeResponse(f.get());
setLastTableIndex(responseParameters.entries, responseParameters.tableIndex);
return responseParameters.entries;
} catch (Exception e) {
throw ExceptionUtil.rethrow(e);
}
}
@Override
protected SerializationService getSerializationService() {
return context.getSerializationService();
}
}