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 * 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,
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package org.apache.kafka.streams;

import org.apache.kafka.common.utils.Bytes;
import org.apache.kafka.streams.errors.TopologyException;
import org.apache.kafka.streams.kstream.Consumed;
import org.apache.kafka.streams.kstream.GlobalKTable;
import org.apache.kafka.streams.kstream.KGroupedStream;
import org.apache.kafka.streams.kstream.KGroupedTable;
import org.apache.kafka.streams.kstream.KStream;
import org.apache.kafka.streams.kstream.KTable;
import org.apache.kafka.streams.kstream.Materialized;
import org.apache.kafka.streams.kstream.Transformer;
import org.apache.kafka.streams.kstream.ValueTransformer;
import org.apache.kafka.streams.kstream.internals.ConsumedInternal;
import org.apache.kafka.streams.kstream.internals.InternalStreamsBuilder;
import org.apache.kafka.streams.kstream.internals.MaterializedInternal;
import org.apache.kafka.streams.processor.StateStore;
import org.apache.kafka.streams.processor.TimestampExtractor;
import org.apache.kafka.streams.processor.api.Processor;
import org.apache.kafka.streams.processor.api.ProcessorSupplier;
import org.apache.kafka.streams.processor.internals.InternalTopologyBuilder;
import org.apache.kafka.streams.processor.internals.ProcessorAdapter;
import org.apache.kafka.streams.processor.internals.ProcessorNode;
import org.apache.kafka.streams.processor.internals.SourceNode;
import org.apache.kafka.streams.state.KeyValueStore;
import org.apache.kafka.streams.state.ReadOnlyKeyValueStore;
import org.apache.kafka.streams.state.StoreBuilder;

import java.util.Collection;
import java.util.Collections;
import java.util.Objects;
import java.util.Properties;
import java.util.regex.Pattern;

/**
 * {@code StreamsBuilder} provide the high-level Kafka Streams DSL to specify a Kafka Streams topology.
 *
 * 

* It is a requirement that the processing logic ({@link Topology}) be defined in a deterministic way, * as in, the order in which all operators are added must be predictable and the same across all application * instances. * Topologies are only identical if all operators are added in the same order. * If different {@link KafkaStreams} instances of the same application build different topologies the result may be * incompatible runtime code and unexpected results or errors * * @see Topology * @see KStream * @see KTable * @see GlobalKTable */ public class StreamsBuilder { /** The actual topology that is constructed by this StreamsBuilder. */ private final Topology topology = new Topology(); /** The topology's internal builder. */ final InternalTopologyBuilder internalTopologyBuilder = topology.internalTopologyBuilder; private final InternalStreamsBuilder internalStreamsBuilder = new InternalStreamsBuilder(internalTopologyBuilder); /** * Create a {@link KStream} from the specified topic. * The default {@code "auto.offset.reset"} strategy, default {@link TimestampExtractor}, and default key and value * deserializers as specified in the {@link StreamsConfig config} are used. *

* If multiple topics are specified there is no ordering guarantee for records from different topics. *

* Note that the specified input topic must be partitioned by key. * If this is not the case it is the user's responsibility to repartition the data before any key based operation * (like aggregation or join) is applied to the returned {@link KStream}. * * @param topic the topic name; cannot be {@code null} * @return a {@link KStream} for the specified topic */ public synchronized KStream stream(final String topic) { return stream(Collections.singleton(topic)); } /** * Create a {@link KStream} from the specified topic. * The {@code "auto.offset.reset"} strategy, {@link TimestampExtractor}, key and value deserializers * are defined by the options in {@link Consumed} are used. *

* Note that the specified input topic must be partitioned by key. * If this is not the case it is the user's responsibility to repartition the data before any key based operation * (like aggregation or join) is applied to the returned {@link KStream}. * * @param topic the topic names; cannot be {@code null} * @param consumed the instance of {@link Consumed} used to define optional parameters * @return a {@link KStream} for the specified topic */ public synchronized KStream stream(final String topic, final Consumed consumed) { return stream(Collections.singleton(topic), consumed); } /** * Create a {@link KStream} from the specified topics. * The default {@code "auto.offset.reset"} strategy, default {@link TimestampExtractor}, and default key and value * deserializers as specified in the {@link StreamsConfig config} are used. *

* If multiple topics are specified there is no ordering guarantee for records from different topics. *

* Note that the specified input topics must be partitioned by key. * If this is not the case it is the user's responsibility to repartition the data before any key based operation * (like aggregation or join) is applied to the returned {@link KStream}. * * @param topics the topic names; must contain at least one topic name * @return a {@link KStream} for the specified topics */ public synchronized KStream stream(final Collection topics) { return stream(topics, Consumed.with(null, null, null, null)); } /** * Create a {@link KStream} from the specified topics. * The {@code "auto.offset.reset"} strategy, {@link TimestampExtractor}, key and value deserializers * are defined by the options in {@link Consumed} are used. *

* If multiple topics are specified there is no ordering guarantee for records from different topics. *

* Note that the specified input topics must be partitioned by key. * If this is not the case it is the user's responsibility to repartition the data before any key based operation * (like aggregation or join) is applied to the returned {@link KStream}. * * @param topics the topic names; must contain at least one topic name * @param consumed the instance of {@link Consumed} used to define optional parameters * @return a {@link KStream} for the specified topics */ public synchronized KStream stream(final Collection topics, final Consumed consumed) { Objects.requireNonNull(topics, "topics can't be null"); Objects.requireNonNull(consumed, "consumed can't be null"); return internalStreamsBuilder.stream(topics, new ConsumedInternal<>(consumed)); } /** * Create a {@link KStream} from the specified topic pattern. * The default {@code "auto.offset.reset"} strategy, default {@link TimestampExtractor}, and default key and value * deserializers as specified in the {@link StreamsConfig config} are used. *

* If multiple topics are matched by the specified pattern, the created {@link KStream} will read data from all of * them and there is no ordering guarantee between records from different topics. This also means that the work * will not be parallelized for multiple topics, and the number of tasks will scale with the maximum partition * count of any matching topic rather than the total number of partitions across all topics. *

* Note that the specified input topics must be partitioned by key. * If this is not the case it is the user's responsibility to repartition the data before any key based operation * (like aggregation or join) is applied to the returned {@link KStream}. * * @param topicPattern the pattern to match for topic names * @return a {@link KStream} for topics matching the regex pattern. */ public synchronized KStream stream(final Pattern topicPattern) { return stream(topicPattern, Consumed.with(null, null)); } /** * Create a {@link KStream} from the specified topic pattern. * The {@code "auto.offset.reset"} strategy, {@link TimestampExtractor}, key and value deserializers * are defined by the options in {@link Consumed} are used. *

* If multiple topics are matched by the specified pattern, the created {@link KStream} will read data from all of * them and there is no ordering guarantee between records from different topics. This also means that the work * will not be parallelized for multiple topics, and the number of tasks will scale with the maximum partition * count of any matching topic rather than the total number of partitions across all topics. *

* Note that the specified input topics must be partitioned by key. * If this is not the case it is the user's responsibility to repartition the data before any key based operation * (like aggregation or join) is applied to the returned {@link KStream}. * * @param topicPattern the pattern to match for topic names * @param consumed the instance of {@link Consumed} used to define optional parameters * @return a {@link KStream} for topics matching the regex pattern. */ public synchronized KStream stream(final Pattern topicPattern, final Consumed consumed) { Objects.requireNonNull(topicPattern, "topicPattern can't be null"); Objects.requireNonNull(consumed, "consumed can't be null"); return internalStreamsBuilder.stream(topicPattern, new ConsumedInternal<>(consumed)); } /** * Create a {@link KTable} for the specified topic. * The {@code "auto.offset.reset"} strategy, {@link TimestampExtractor}, key and value deserializers * are defined by the options in {@link Consumed} are used. * Input {@link KeyValue records} with {@code null} key will be dropped. *

* Note that the specified input topic must be partitioned by key. * If this is not the case the returned {@link KTable} will be corrupted. *

* The resulting {@link KTable} will be materialized in a local {@link KeyValueStore} using the given * {@code Materialized} instance. * An internal changelog topic is created by default. Because the source topic can * be used for recovery, you can avoid creating the changelog topic by setting * the {@code "topology.optimization"} to {@code "all"} in the {@link StreamsConfig}. *

* You should only specify serdes in the {@link Consumed} instance as these will also be used to overwrite the * serdes in {@link Materialized}, i.e., *

 {@code
     * streamBuilder.table(topic, Consumed.with(Serde.String(), Serde.String()), Materialized.as(storeName))
     * }
     * 
* To query the local {@link ReadOnlyKeyValueStore} it must be obtained via * {@link KafkaStreams#store(StoreQueryParameters) KafkaStreams#store(...)}: *
{@code
     * KafkaStreams streams = ...
     * ReadOnlyKeyValueStore> localStore = streams.store(queryableStoreName, QueryableStoreTypes.>timestampedKeyValueStore());
     * K key = "some-key";
     * ValueAndTimestamp valueForKey = localStore.get(key); // key must be local (application state is shared over all running Kafka Streams instances)
     * }
* For non-local keys, a custom RPC mechanism must be implemented using {@link KafkaStreams#allMetadata()} to * query the value of the key on a parallel running instance of your Kafka Streams application. * * @param topic the topic name; cannot be {@code null} * @param consumed the instance of {@link Consumed} used to define optional parameters; cannot be {@code null} * @param materialized the instance of {@link Materialized} used to materialize a state store; cannot be {@code null} * @return a {@link KTable} for the specified topic */ public synchronized KTable table(final String topic, final Consumed consumed, final Materialized> materialized) { Objects.requireNonNull(topic, "topic can't be null"); Objects.requireNonNull(consumed, "consumed can't be null"); Objects.requireNonNull(materialized, "materialized can't be null"); final ConsumedInternal consumedInternal = new ConsumedInternal<>(consumed); materialized.withKeySerde(consumedInternal.keySerde()).withValueSerde(consumedInternal.valueSerde()); final MaterializedInternal> materializedInternal = new MaterializedInternal<>(materialized, internalStreamsBuilder, topic + "-"); return internalStreamsBuilder.table(topic, consumedInternal, materializedInternal); } /** * Create a {@link KTable} for the specified topic. * The default {@code "auto.offset.reset"} strategy and default key and value deserializers as specified in the * {@link StreamsConfig config} are used. * Input {@link KeyValue records} with {@code null} key will be dropped. *

* Note that the specified input topics must be partitioned by key. * If this is not the case the returned {@link KTable} will be corrupted. *

* The resulting {@link KTable} will be materialized in a local {@link KeyValueStore} with an internal * store name. Note that store name may not be queryable through Interactive Queries. * An internal changelog topic is created by default. Because the source topic can * be used for recovery, you can avoid creating the changelog topic by setting * the {@code "topology.optimization"} to {@code "all"} in the {@link StreamsConfig}. * * @param topic the topic name; cannot be {@code null} * @return a {@link KTable} for the specified topic */ public synchronized KTable table(final String topic) { return table(topic, new ConsumedInternal<>()); } /** * Create a {@link KTable} for the specified topic. * The {@code "auto.offset.reset"} strategy, {@link TimestampExtractor}, key and value deserializers * are defined by the options in {@link Consumed} are used. * Input {@link KeyValue records} with {@code null} key will be dropped. *

* Note that the specified input topics must be partitioned by key. * If this is not the case the returned {@link KTable} will be corrupted. *

* The resulting {@link KTable} will be materialized in a local {@link KeyValueStore} with an internal * store name. Note that store name may not be queryable through Interactive Queries. * An internal changelog topic is created by default. Because the source topic can * be used for recovery, you can avoid creating the changelog topic by setting * the {@code "topology.optimization"} to {@code "all"} in the {@link StreamsConfig}. * * @param topic the topic name; cannot be {@code null} * @param consumed the instance of {@link Consumed} used to define optional parameters; cannot be {@code null} * @return a {@link KTable} for the specified topic */ public synchronized KTable table(final String topic, final Consumed consumed) { Objects.requireNonNull(topic, "topic can't be null"); Objects.requireNonNull(consumed, "consumed can't be null"); final ConsumedInternal consumedInternal = new ConsumedInternal<>(consumed); final MaterializedInternal> materializedInternal = new MaterializedInternal<>( Materialized.with(consumedInternal.keySerde(), consumedInternal.valueSerde()), internalStreamsBuilder, topic + "-"); return internalStreamsBuilder.table(topic, consumedInternal, materializedInternal); } /** * Create a {@link KTable} for the specified topic. * The default {@code "auto.offset.reset"} strategy as specified in the {@link StreamsConfig config} are used. * Key and value deserializers as defined by the options in {@link Materialized} are used. * Input {@link KeyValue records} with {@code null} key will be dropped. *

* Note that the specified input topics must be partitioned by key. * If this is not the case the returned {@link KTable} will be corrupted. *

* The resulting {@link KTable} will be materialized in a local {@link KeyValueStore} using the {@link Materialized} instance. * An internal changelog topic is created by default. Because the source topic can * be used for recovery, you can avoid creating the changelog topic by setting * the {@code "topology.optimization"} to {@code "all"} in the {@link StreamsConfig}. * * @param topic the topic name; cannot be {@code null} * @param materialized the instance of {@link Materialized} used to materialize a state store; cannot be {@code null} * @return a {@link KTable} for the specified topic */ public synchronized KTable table(final String topic, final Materialized> materialized) { Objects.requireNonNull(topic, "topic can't be null"); Objects.requireNonNull(materialized, "materialized can't be null"); final MaterializedInternal> materializedInternal = new MaterializedInternal<>(materialized, internalStreamsBuilder, topic + "-"); final ConsumedInternal consumedInternal = new ConsumedInternal<>(Consumed.with(materializedInternal.keySerde(), materializedInternal.valueSerde())); return internalStreamsBuilder.table(topic, consumedInternal, materializedInternal); } /** * Create a {@link GlobalKTable} for the specified topic. * Input {@link KeyValue records} with {@code null} key will be dropped. *

* The resulting {@link GlobalKTable} will be materialized in a local {@link KeyValueStore} with an internal * store name. Note that store name may not be queryable through Interactive Queries. * No internal changelog topic is created since the original input topic can be used for recovery (cf. * methods of {@link KGroupedStream} and {@link KGroupedTable} that return a {@link KTable}). *

* Note that {@link GlobalKTable} always applies {@code "auto.offset.reset"} strategy {@code "earliest"} * regardless of the specified value in {@link StreamsConfig} or {@link Consumed}. * * @param topic the topic name; cannot be {@code null} * @param consumed the instance of {@link Consumed} used to define optional parameters * @return a {@link GlobalKTable} for the specified topic */ public synchronized GlobalKTable globalTable(final String topic, final Consumed consumed) { Objects.requireNonNull(topic, "topic can't be null"); Objects.requireNonNull(consumed, "consumed can't be null"); final ConsumedInternal consumedInternal = new ConsumedInternal<>(consumed); final MaterializedInternal> materializedInternal = new MaterializedInternal<>( Materialized.with(consumedInternal.keySerde(), consumedInternal.valueSerde()), internalStreamsBuilder, topic + "-"); return internalStreamsBuilder.globalTable(topic, consumedInternal, materializedInternal); } /** * Create a {@link GlobalKTable} for the specified topic. * The default key and value deserializers as specified in the {@link StreamsConfig config} are used. * Input {@link KeyValue records} with {@code null} key will be dropped. *

* The resulting {@link GlobalKTable} will be materialized in a local {@link KeyValueStore} with an internal * store name. Note that store name may not be queryable through Interactive Queries. * No internal changelog topic is created since the original input topic can be used for recovery (cf. * methods of {@link KGroupedStream} and {@link KGroupedTable} that return a {@link KTable}). *

* Note that {@link GlobalKTable} always applies {@code "auto.offset.reset"} strategy {@code "earliest"} * regardless of the specified value in {@link StreamsConfig}. * * @param topic the topic name; cannot be {@code null} * @return a {@link GlobalKTable} for the specified topic */ public synchronized GlobalKTable globalTable(final String topic) { return globalTable(topic, Consumed.with(null, null)); } /** * Create a {@link GlobalKTable} for the specified topic. * * Input {@link KeyValue} pairs with {@code null} key will be dropped. *

* The resulting {@link GlobalKTable} will be materialized in a local {@link KeyValueStore} configured with * the provided instance of {@link Materialized}. * However, no internal changelog topic is created since the original input topic can be used for recovery (cf. * methods of {@link KGroupedStream} and {@link KGroupedTable} that return a {@link KTable}). *

* You should only specify serdes in the {@link Consumed} instance as these will also be used to overwrite the * serdes in {@link Materialized}, i.e., *

 {@code
     * streamBuilder.globalTable(topic, Consumed.with(Serde.String(), Serde.String()), Materialized.as(storeName))
     * }
     * 
* To query the local {@link ReadOnlyKeyValueStore} it must be obtained via * {@link KafkaStreams#store(StoreQueryParameters) KafkaStreams#store(...)}: *
{@code
     * KafkaStreams streams = ...
     * ReadOnlyKeyValueStore> localStore = streams.store(queryableStoreName, QueryableStoreTypes.>timestampedKeyValueStore());
     * K key = "some-key";
     * ValueAndTimestamp valueForKey = localStore.get(key);
     * }
* Note that {@link GlobalKTable} always applies {@code "auto.offset.reset"} strategy {@code "earliest"} * regardless of the specified value in {@link StreamsConfig} or {@link Consumed}. * * @param topic the topic name; cannot be {@code null} * @param consumed the instance of {@link Consumed} used to define optional parameters; can't be {@code null} * @param materialized the instance of {@link Materialized} used to materialize a state store; cannot be {@code null} * @return a {@link GlobalKTable} for the specified topic */ public synchronized GlobalKTable globalTable(final String topic, final Consumed consumed, final Materialized> materialized) { Objects.requireNonNull(topic, "topic can't be null"); Objects.requireNonNull(consumed, "consumed can't be null"); Objects.requireNonNull(materialized, "materialized can't be null"); final ConsumedInternal consumedInternal = new ConsumedInternal<>(consumed); // always use the serdes from consumed materialized.withKeySerde(consumedInternal.keySerde()).withValueSerde(consumedInternal.valueSerde()); final MaterializedInternal> materializedInternal = new MaterializedInternal<>(materialized, internalStreamsBuilder, topic + "-"); return internalStreamsBuilder.globalTable(topic, consumedInternal, materializedInternal); } /** * Create a {@link GlobalKTable} for the specified topic. * * Input {@link KeyValue} pairs with {@code null} key will be dropped. *

* The resulting {@link GlobalKTable} will be materialized in a local {@link KeyValueStore} configured with * the provided instance of {@link Materialized}. * However, no internal changelog topic is created since the original input topic can be used for recovery (cf. * methods of {@link KGroupedStream} and {@link KGroupedTable} that return a {@link KTable}). *

* To query the local {@link ReadOnlyKeyValueStore} it must be obtained via * {@link KafkaStreams#store(StoreQueryParameters) KafkaStreams#store(...)}: *

{@code
     * KafkaStreams streams = ...
     * ReadOnlyKeyValueStore> localStore = streams.store(queryableStoreName, QueryableStoreTypes.>timestampedKeyValueStore());
     * K key = "some-key";
     * ValueAndTimestamp valueForKey = localStore.get(key);
     * }
* Note that {@link GlobalKTable} always applies {@code "auto.offset.reset"} strategy {@code "earliest"} * regardless of the specified value in {@link StreamsConfig}. * * @param topic the topic name; cannot be {@code null} * @param materialized the instance of {@link Materialized} used to materialize a state store; cannot be {@code null} * @return a {@link GlobalKTable} for the specified topic */ public synchronized GlobalKTable globalTable(final String topic, final Materialized> materialized) { Objects.requireNonNull(topic, "topic can't be null"); Objects.requireNonNull(materialized, "materialized can't be null"); final MaterializedInternal> materializedInternal = new MaterializedInternal<>(materialized, internalStreamsBuilder, topic + "-"); return internalStreamsBuilder.globalTable(topic, new ConsumedInternal<>(Consumed.with(materializedInternal.keySerde(), materializedInternal.valueSerde())), materializedInternal); } /** * Adds a state store to the underlying {@link Topology}. *

* It is required to connect state stores to {@link org.apache.kafka.streams.processor.Processor Processors}, {@link Transformer Transformers}, * or {@link ValueTransformer ValueTransformers} before they can be used. * * @param builder the builder used to obtain this state store {@link StateStore} instance * @return itself * @throws TopologyException if state store supplier is already added */ public synchronized StreamsBuilder addStateStore(final StoreBuilder builder) { Objects.requireNonNull(builder, "builder can't be null"); internalStreamsBuilder.addStateStore(builder); return this; } /** * @deprecated Use {@link #addGlobalStore(StoreBuilder, String, Consumed, ProcessorSupplier)} instead. */ @Deprecated public synchronized StreamsBuilder addGlobalStore(final StoreBuilder storeBuilder, final String topic, final String sourceName, final Consumed consumed, final String processorName, final org.apache.kafka.streams.processor.ProcessorSupplier stateUpdateSupplier) { Objects.requireNonNull(storeBuilder, "storeBuilder can't be null"); Objects.requireNonNull(consumed, "consumed can't be null"); internalStreamsBuilder.addGlobalStore( storeBuilder, sourceName, topic, new ConsumedInternal<>(consumed), processorName, () -> ProcessorAdapter.adapt(stateUpdateSupplier.get()) ); return this; } /** * Adds a global {@link StateStore} to the topology. * The {@link StateStore} sources its data from all partitions of the provided input topic. * There will be exactly one instance of this {@link StateStore} per Kafka Streams instance. *

* A {@link SourceNode} with the provided sourceName will be added to consume the data arriving from the partitions * of the input topic. *

* The provided {@link org.apache.kafka.streams.processor.ProcessorSupplier} will be used to create an {@link ProcessorNode} that will receive all * records forwarded from the {@link SourceNode}. NOTE: you should not use the {@code Processor} to insert transformed records into * the global state store. This store uses the source topic as changelog and during restore will insert records directly * from the source. * This {@link ProcessorNode} should be used to keep the {@link StateStore} up-to-date. * The default {@link TimestampExtractor} as specified in the {@link StreamsConfig config} is used. *

* It is not required to connect a global store to {@link org.apache.kafka.streams.processor.Processor Processors}, {@link Transformer Transformers}, * or {@link ValueTransformer ValueTransformer}; those have read-only access to all global stores by default. *

* The supplier should always generate a new instance each time {@link ProcessorSupplier#get()} gets called. Creating * a single {@link Processor} object and returning the same object reference in {@link ProcessorSupplier#get()} would be * a violation of the supplier pattern and leads to runtime exceptions. * * @param storeBuilder user defined {@link StoreBuilder}; can't be {@code null} * @param topic the topic to source the data from * @param consumed the instance of {@link Consumed} used to define optional parameters; can't be {@code null} * @param stateUpdateSupplier the instance of {@link org.apache.kafka.streams.processor.ProcessorSupplier} * @return itself * @throws TopologyException if the processor of state is already registered * @deprecated Since 2.7.0; use {@link #addGlobalStore(StoreBuilder, String, Consumed, ProcessorSupplier)} instead. */ @Deprecated public synchronized StreamsBuilder addGlobalStore(final StoreBuilder storeBuilder, final String topic, final Consumed consumed, final org.apache.kafka.streams.processor.ProcessorSupplier stateUpdateSupplier) { Objects.requireNonNull(storeBuilder, "storeBuilder can't be null"); Objects.requireNonNull(consumed, "consumed can't be null"); internalStreamsBuilder.addGlobalStore( storeBuilder, topic, new ConsumedInternal<>(consumed), () -> ProcessorAdapter.adapt(stateUpdateSupplier.get()) ); return this; } /** * Adds a global {@link StateStore} to the topology. * The {@link StateStore} sources its data from all partitions of the provided input topic. * There will be exactly one instance of this {@link StateStore} per Kafka Streams instance. *

* A {@link SourceNode} with the provided sourceName will be added to consume the data arriving from the partitions * of the input topic. *

* The provided {@link ProcessorSupplier}} will be used to create an * {@link Processor} that will receive all records forwarded from the {@link SourceNode}. * The supplier should always generate a new instance. Creating a single {@link Processor} object * and returning the same object reference in {@link ProcessorSupplier#get()} is a * violation of the supplier pattern and leads to runtime exceptions. * NOTE: you should not use the {@link Processor} to insert transformed records into * the global state store. This store uses the source topic as changelog and during restore will insert records directly * from the source. * This {@link Processor} should be used to keep the {@link StateStore} up-to-date. * The default {@link TimestampExtractor} as specified in the {@link StreamsConfig config} is used. *

* It is not required to connect a global store to the {@link Processor Processors}, * {@link Transformer Transformers}, or {@link ValueTransformer ValueTransformer}; those have read-only access to all global stores by default. * * @param storeBuilder user defined {@link StoreBuilder}; can't be {@code null} * @param topic the topic to source the data from * @param consumed the instance of {@link Consumed} used to define optional parameters; can't be {@code null} * @param stateUpdateSupplier the instance of {@link ProcessorSupplier} * @return itself * @throws TopologyException if the processor of state is already registered */ public synchronized StreamsBuilder addGlobalStore(final StoreBuilder storeBuilder, final String topic, final Consumed consumed, final ProcessorSupplier stateUpdateSupplier) { Objects.requireNonNull(storeBuilder, "storeBuilder can't be null"); Objects.requireNonNull(consumed, "consumed can't be null"); internalStreamsBuilder.addGlobalStore( storeBuilder, topic, new ConsumedInternal<>(consumed), stateUpdateSupplier ); return this; } /** * Returns the {@link Topology} that represents the specified processing logic. * Note that using this method means no optimizations are performed. * * @return the {@link Topology} that represents the specified processing logic */ public synchronized Topology build() { return build(null); } /** * Returns the {@link Topology} that represents the specified processing logic and accepts * a {@link Properties} instance used to indicate whether to optimize topology or not. * * @param props the {@link Properties} used for building possibly optimized topology * @return the {@link Topology} that represents the specified processing logic */ public synchronized Topology build(final Properties props) { internalStreamsBuilder.buildAndOptimizeTopology(props); return topology; } }





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