org.apache.kafka.streams.kstream.Consumed Maven / Gradle / Ivy
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* 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.kstream;
import org.apache.kafka.common.serialization.Serde;
import org.apache.kafka.streams.StreamsBuilder;
import org.apache.kafka.streams.Topology;
import org.apache.kafka.streams.processor.TimestampExtractor;
import java.util.Objects;
/**
* The {@code Consumed} class is used to define the optional parameters when using {@link StreamsBuilder} to
* build instances of {@link KStream}, {@link KTable}, and {@link GlobalKTable}.
*
* For example, you can read a topic as {@link KStream} with a custom timestamp extractor and specify the corresponding
* key and value serdes like:
*
{@code
* StreamsBuilder builder = new StreamsBuilder();
* KStream stream = builder.stream(
* "topicName",
* Consumed.with(Serdes.String(), Serdes.Long())
* .withTimestampExtractor(new LogAndSkipOnInvalidTimestamp()));
* }
* Similarly, you can read a topic as {@link KTable} with a custom {@code auto.offset.reset} configuration and force a
* state store {@link org.apache.kafka.streams.kstream.Materialized materialization} to access the content via
* interactive queries:
* {@code
* StreamsBuilder builder = new StreamsBuilder();
* KTable table = builder.table(
* "topicName",
* Consumed.with(AutoOffsetReset.LATEST),
* Materialized.as("queryable-store-name"));
* }
*
* @param type of record key
* @param type of record value
*/
public class Consumed implements NamedOperation> {
protected Serde keySerde;
protected Serde valueSerde;
protected TimestampExtractor timestampExtractor;
protected Topology.AutoOffsetReset resetPolicy;
protected String processorName;
private Consumed(final Serde keySerde,
final Serde valueSerde,
final TimestampExtractor timestampExtractor,
final Topology.AutoOffsetReset resetPolicy,
final String processorName) {
this.keySerde = keySerde;
this.valueSerde = valueSerde;
this.timestampExtractor = timestampExtractor;
this.resetPolicy = resetPolicy;
this.processorName = processorName;
}
/**
* Create an instance of {@link Consumed} from an existing instance.
* @param consumed the instance of {@link Consumed} to copy
*/
protected Consumed(final Consumed consumed) {
this(consumed.keySerde,
consumed.valueSerde,
consumed.timestampExtractor,
consumed.resetPolicy,
consumed.processorName
);
}
/**
* Create an instance of {@link Consumed} with the supplied arguments. {@code null} values are acceptable.
*
* @param keySerde the key serde. If {@code null} the default key serde from config will be used
* @param valueSerde the value serde. If {@code null} the default value serde from config will be used
* @param timestampExtractor the timestamp extractor to used. If {@code null} the default timestamp extractor from config will be used
* @param resetPolicy the offset reset policy to be used. If {@code null} the default reset policy from config will be used
* @param key type
* @param value type
* @return a new instance of {@link Consumed}
*/
public static Consumed with(final Serde keySerde,
final Serde valueSerde,
final TimestampExtractor timestampExtractor,
final Topology.AutoOffsetReset resetPolicy) {
return new Consumed<>(keySerde, valueSerde, timestampExtractor, resetPolicy, null);
}
/**
* Create an instance of {@link Consumed} with key and value {@link Serde}s.
*
* @param keySerde the key serde. If {@code null} the default key serde from config will be used
* @param valueSerde the value serde. If {@code null} the default value serde from config will be used
* @param key type
* @param value type
* @return a new instance of {@link Consumed}
*/
public static Consumed with(final Serde keySerde,
final Serde valueSerde) {
return new Consumed<>(keySerde, valueSerde, null, null, null);
}
/**
* Create an instance of {@link Consumed} with a {@link TimestampExtractor}.
*
* @param timestampExtractor the timestamp extractor to used. If {@code null} the default timestamp extractor from config will be used
* @param key type
* @param value type
* @return a new instance of {@link Consumed}
*/
public static Consumed with(final TimestampExtractor timestampExtractor) {
return new Consumed<>(null, null, timestampExtractor, null, null);
}
/**
* Create an instance of {@link Consumed} with a {@link org.apache.kafka.streams.Topology.AutoOffsetReset Topology.AutoOffsetReset}.
*
* @param resetPolicy the offset reset policy to be used. If {@code null} the default reset policy from config will be used
* @param key type
* @param value type
* @return a new instance of {@link Consumed}
*/
public static Consumed with(final Topology.AutoOffsetReset resetPolicy) {
return new Consumed<>(null, null, null, resetPolicy, null);
}
/**
* Create an instance of {@link Consumed} with provided processor name.
*
* @param processorName the processor name to be used. If {@code null} a default processor name will be generated
* @param key type
* @param value type
* @return a new instance of {@link Consumed}
*/
public static Consumed as(final String processorName) {
return new Consumed<>(null, null, null, null, processorName);
}
/**
* Configure the instance of {@link Consumed} with a key {@link Serde}.
*
* @param keySerde the key serde. If {@code null}the default key serde from config will be used
* @return this
*/
public Consumed withKeySerde(final Serde keySerde) {
this.keySerde = keySerde;
return this;
}
/**
* Configure the instance of {@link Consumed} with a value {@link Serde}.
*
* @param valueSerde the value serde. If {@code null} the default value serde from config will be used
* @return this
*/
public Consumed withValueSerde(final Serde valueSerde) {
this.valueSerde = valueSerde;
return this;
}
/**
* Configure the instance of {@link Consumed} with a {@link TimestampExtractor}.
*
* @param timestampExtractor the timestamp extractor to used. If {@code null} the default timestamp extractor from config will be used
* @return this
*/
public Consumed withTimestampExtractor(final TimestampExtractor timestampExtractor) {
this.timestampExtractor = timestampExtractor;
return this;
}
/**
* Configure the instance of {@link Consumed} with a {@link org.apache.kafka.streams.Topology.AutoOffsetReset Topology.AutoOffsetReset}.
*
* @param resetPolicy the offset reset policy to be used. If {@code null} the default reset policy from config will be used
* @return this
*/
public Consumed withOffsetResetPolicy(final Topology.AutoOffsetReset resetPolicy) {
this.resetPolicy = resetPolicy;
return this;
}
/**
* Configure the instance of {@link Consumed} with a processor name.
*
* @param processorName the processor name to be used. If {@code null} a default processor name will be generated
* @return this
*/
@Override
public Consumed withName(final String processorName) {
this.processorName = processorName;
return this;
}
@Override
public boolean equals(final Object o) {
if (this == o) {
return true;
}
if (o == null || getClass() != o.getClass()) {
return false;
}
final Consumed consumed = (Consumed) o;
return Objects.equals(keySerde, consumed.keySerde) &&
Objects.equals(valueSerde, consumed.valueSerde) &&
Objects.equals(timestampExtractor, consumed.timestampExtractor) &&
resetPolicy == consumed.resetPolicy;
}
@Override
public int hashCode() {
return Objects.hash(keySerde, valueSerde, timestampExtractor, resetPolicy);
}
}