kafka WrappingStoreProvider 源码

kafka WrappingStoreProvider 代码

文件路径：/streams/src/main/java/org/apache/kafka/streams/state/internals/WrappingStoreProvider.java

/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements. See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You 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 org.apache.kafka.streams.state.internals;

import org.apache.kafka.streams.StoreQueryParameters;
import org.apache.kafka.streams.errors.InvalidStateStoreException;
import org.apache.kafka.streams.errors.InvalidStateStorePartitionException;
import org.apache.kafka.streams.state.QueryableStoreType;

import java.util.ArrayList;
import java.util.Collection;
import java.util.List;

/**
 * Provides a wrapper over multiple underlying {@link StateStoreProvider}s
 */
public class WrappingStoreProvider implements StateStoreProvider {

    private final Collection<StreamThreadStateStoreProvider> storeProviders;
    private StoreQueryParameters storeQueryParameters;

    WrappingStoreProvider(final Collection<StreamThreadStateStoreProvider> storeProviders,
                          final StoreQueryParameters storeQueryParameters) {
        this.storeProviders = storeProviders;
        this.storeQueryParameters = storeQueryParameters;
    }

    //visible for testing
    public void setStoreQueryParameters(final StoreQueryParameters storeQueryParameters) {
        this.storeQueryParameters = storeQueryParameters;
    }

    @Override
    public <T> List<T> stores(final String storeName,
                              final QueryableStoreType<T> queryableStoreType) {
        final List<T> allStores = new ArrayList<>();
        for (final StreamThreadStateStoreProvider storeProvider : storeProviders) {
            final List<T> stores = storeProvider.stores(storeQueryParameters);
            if (!stores.isEmpty()) {
                allStores.addAll(stores);
                if (storeQueryParameters.partition() != null) {
                    break;
                }
            }
        }
        if (allStores.isEmpty()) {
            if (storeQueryParameters.partition() != null) {
                throw new InvalidStateStorePartitionException(
                        String.format("The specified partition %d for store %s does not exist.",
                                storeQueryParameters.partition(),
                                storeName));
            }
            throw new InvalidStateStoreException("The state store, " + storeName + ", may have migrated to another instance.");
        }
        return allStores;
    }
}

相关信息

kafka 源码目录

相关文章

kafka AbstractDualSchemaRocksDBSegmentedBytesStore 源码

kafka AbstractMergedSortedCacheStoreIterator 源码

kafka AbstractRocksDBSegmentedBytesStore 源码

kafka AbstractRocksDBTimeOrderedSegmentedBytesStore 源码

kafka AbstractSegments 源码

kafka AbstractStoreBuilder 源码

kafka BatchWritingStore 源码

kafka BlockBasedTableConfigWithAccessibleCache 源码

kafka BufferKey 源码

kafka BufferValue 源码