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使用SDK适用于 Java 2.x 的 Kinesis 示例
以下代码示例向您展示了如何使用 Amazon SDK for Java 2.x 与 Kinesis 配合使用来执行操作和实现常见场景。
操作是大型程序的代码摘录,必须在上下文中运行。您可以通过操作了解如何调用单个服务函数,还可以通过函数相关场景的上下文查看操作。
每个示例都包含一个指向完整源代码的链接,您可以在其中找到有关如何在上下文中设置和运行代码的说明。
操作
以下代码示例演示如何使用 CreateStream
。
- SDK适用于 Java 2.x
-
注意
还有更多相关信息 GitHub。查找完整示例,学习如何在 Amazon 代码示例存储库
中进行设置和运行。 import software.amazon.awssdk.regions.Region; import software.amazon.awssdk.services.kinesis.KinesisClient; import software.amazon.awssdk.services.kinesis.model.CreateStreamRequest; import software.amazon.awssdk.services.kinesis.model.KinesisException; /** * Before running this Java V2 code example, set up your development * environment, including your credentials. * * For more information, see the following documentation topic: * * https://docs.aws.amazon.com/sdk-for-java/latest/developer-guide/get-started.html */ public class CreateDataStream { public static void main(String[] args) { final String usage = """ Usage: <streamName> Where: streamName - The Amazon Kinesis data stream (for example, StockTradeStream). """; if (args.length != 1) { System.out.println(usage); System.exit(1); } String streamName = args[0]; Region region = Region.US_EAST_1; KinesisClient kinesisClient = KinesisClient.builder() .region(region) .build(); createStream(kinesisClient, streamName); System.out.println("Done"); kinesisClient.close(); } public static void createStream(KinesisClient kinesisClient, String streamName) { try { CreateStreamRequest streamReq = CreateStreamRequest.builder() .streamName(streamName) .shardCount(1) .build(); kinesisClient.createStream(streamReq); } catch (KinesisException e) { System.err.println(e.getMessage()); System.exit(1); } } }
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有关API详细信息,请参阅 “Amazon SDK for Java 2.x API参考 CreateStream” 中的。
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以下代码示例演示如何使用 DeleteStream
。
- SDK适用于 Java 2.x
-
注意
还有更多相关信息 GitHub。查找完整示例,学习如何在 Amazon 代码示例存储库
中进行设置和运行。 import software.amazon.awssdk.regions.Region; import software.amazon.awssdk.services.kinesis.KinesisClient; import software.amazon.awssdk.services.kinesis.model.DeleteStreamRequest; import software.amazon.awssdk.services.kinesis.model.KinesisException; /** * Before running this Java V2 code example, set up your development * environment, including your credentials. * * For more information, see the following documentation topic: * * https://docs.aws.amazon.com/sdk-for-java/latest/developer-guide/get-started.html */ public class DeleteDataStream { public static void main(String[] args) { final String usage = """ Usage: <streamName> Where: streamName - The Amazon Kinesis data stream (for example, StockTradeStream) """; if (args.length != 1) { System.out.println(usage); System.exit(1); } String streamName = args[0]; Region region = Region.US_EAST_1; KinesisClient kinesisClient = KinesisClient.builder() .region(region) .build(); deleteStream(kinesisClient, streamName); kinesisClient.close(); System.out.println("Done"); } public static void deleteStream(KinesisClient kinesisClient, String streamName) { try { DeleteStreamRequest delStream = DeleteStreamRequest.builder() .streamName(streamName) .build(); kinesisClient.deleteStream(delStream); } catch (KinesisException e) { System.err.println(e.getMessage()); System.exit(1); } } }
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有关API详细信息,请参阅 “Amazon SDK for Java 2.x API参考 DeleteStream” 中的。
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以下代码示例演示如何使用 GetRecords
。
- SDK适用于 Java 2.x
-
注意
还有更多相关信息 GitHub。查找完整示例,学习如何在 Amazon 代码示例存储库
中进行设置和运行。 import software.amazon.awssdk.core.SdkBytes; import software.amazon.awssdk.regions.Region; import software.amazon.awssdk.services.kinesis.KinesisClient; import software.amazon.awssdk.services.kinesis.model.DescribeStreamResponse; import software.amazon.awssdk.services.kinesis.model.DescribeStreamRequest; import software.amazon.awssdk.services.kinesis.model.Shard; import software.amazon.awssdk.services.kinesis.model.GetShardIteratorRequest; import software.amazon.awssdk.services.kinesis.model.GetShardIteratorResponse; import software.amazon.awssdk.services.kinesis.model.Record; import software.amazon.awssdk.services.kinesis.model.GetRecordsRequest; import software.amazon.awssdk.services.kinesis.model.GetRecordsResponse; import java.util.ArrayList; import java.util.List; /** * Before running this Java V2 code example, set up your development * environment, including your credentials. * * For more information, see the following documentation topic: * * https://docs.aws.amazon.com/sdk-for-java/latest/developer-guide/get-started.html */ public class GetRecords { public static void main(String[] args) { final String usage = """ Usage: <streamName> Where: streamName - The Amazon Kinesis data stream to read from (for example, StockTradeStream). """; if (args.length != 1) { System.out.println(usage); System.exit(1); } String streamName = args[0]; Region region = Region.US_EAST_1; KinesisClient kinesisClient = KinesisClient.builder() .region(region) .build(); getStockTrades(kinesisClient, streamName); kinesisClient.close(); } public static void getStockTrades(KinesisClient kinesisClient, String streamName) { String shardIterator; String lastShardId = null; DescribeStreamRequest describeStreamRequest = DescribeStreamRequest.builder() .streamName(streamName) .build(); List<Shard> shards = new ArrayList<>(); DescribeStreamResponse streamRes; do { streamRes = kinesisClient.describeStream(describeStreamRequest); shards.addAll(streamRes.streamDescription().shards()); if (shards.size() > 0) { lastShardId = shards.get(shards.size() - 1).shardId(); } } while (streamRes.streamDescription().hasMoreShards()); GetShardIteratorRequest itReq = GetShardIteratorRequest.builder() .streamName(streamName) .shardIteratorType("TRIM_HORIZON") .shardId(lastShardId) .build(); GetShardIteratorResponse shardIteratorResult = kinesisClient.getShardIterator(itReq); shardIterator = shardIteratorResult.shardIterator(); // Continuously read data records from shard. List<Record> records; // Create new GetRecordsRequest with existing shardIterator. // Set maximum records to return to 1000. GetRecordsRequest recordsRequest = GetRecordsRequest.builder() .shardIterator(shardIterator) .limit(1000) .build(); GetRecordsResponse result = kinesisClient.getRecords(recordsRequest); // Put result into record list. Result may be empty. records = result.records(); // Print records for (Record record : records) { SdkBytes byteBuffer = record.data(); System.out.printf("Seq No: %s - %s%n", record.sequenceNumber(), new String(byteBuffer.asByteArray())); } } }
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有关API详细信息,请参阅 “Amazon SDK for Java 2.x API参考 GetRecords” 中的。
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以下代码示例演示如何使用 PutRecord
。
- SDK适用于 Java 2.x
-
注意
还有更多相关信息 GitHub。查找完整示例,学习如何在 Amazon 代码示例存储库
中进行设置和运行。 import software.amazon.awssdk.core.SdkBytes; import software.amazon.awssdk.regions.Region; import software.amazon.awssdk.services.kinesis.KinesisClient; import software.amazon.awssdk.services.kinesis.model.PutRecordRequest; import software.amazon.awssdk.services.kinesis.model.KinesisException; import software.amazon.awssdk.services.kinesis.model.DescribeStreamRequest; import software.amazon.awssdk.services.kinesis.model.DescribeStreamResponse; /** * Before running this Java V2 code example, set up your development * environment, including your credentials. * * For more information, see the following documentation topic: * * https://docs.aws.amazon.com/sdk-for-java/latest/developer-guide/get-started.html */ public class StockTradesWriter { public static void main(String[] args) { final String usage = """ Usage: <streamName> Where: streamName - The Amazon Kinesis data stream to which records are written (for example, StockTradeStream) """; if (args.length != 1) { System.out.println(usage); System.exit(1); } String streamName = args[0]; Region region = Region.US_EAST_1; KinesisClient kinesisClient = KinesisClient.builder() .region(region) .build(); // Ensure that the Kinesis Stream is valid. validateStream(kinesisClient, streamName); setStockData(kinesisClient, streamName); kinesisClient.close(); } public static void setStockData(KinesisClient kinesisClient, String streamName) { try { // Repeatedly send stock trades with a 100 milliseconds wait in between. StockTradeGenerator stockTradeGenerator = new StockTradeGenerator(); // Put in 50 Records for this example. int index = 50; for (int x = 0; x < index; x++) { StockTrade trade = stockTradeGenerator.getRandomTrade(); sendStockTrade(trade, kinesisClient, streamName); Thread.sleep(100); } } catch (KinesisException | InterruptedException e) { System.err.println(e.getMessage()); System.exit(1); } System.out.println("Done"); } private static void sendStockTrade(StockTrade trade, KinesisClient kinesisClient, String streamName) { byte[] bytes = trade.toJsonAsBytes(); // The bytes could be null if there is an issue with the JSON serialization by // the Jackson JSON library. if (bytes == null) { System.out.println("Could not get JSON bytes for stock trade"); return; } System.out.println("Putting trade: " + trade); PutRecordRequest request = PutRecordRequest.builder() .partitionKey(trade.getTickerSymbol()) // We use the ticker symbol as the partition key, explained in // the Supplemental Information section below. .streamName(streamName) .data(SdkBytes.fromByteArray(bytes)) .build(); try { kinesisClient.putRecord(request); } catch (KinesisException e) { System.err.println(e.getMessage()); } } private static void validateStream(KinesisClient kinesisClient, String streamName) { try { DescribeStreamRequest describeStreamRequest = DescribeStreamRequest.builder() .streamName(streamName) .build(); DescribeStreamResponse describeStreamResponse = kinesisClient.describeStream(describeStreamRequest); if (!describeStreamResponse.streamDescription().streamStatus().toString().equals("ACTIVE")) { System.err.println("Stream " + streamName + " is not active. Please wait a few moments and try again."); System.exit(1); } } catch (KinesisException e) { System.err.println("Error found while describing the stream " + streamName); System.err.println(e); System.exit(1); } } }
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有关API详细信息,请参阅 “Amazon SDK for Java 2.x API参考 PutRecord” 中的。
-
无服务器示例
以下代码示例展示了如何实现一个 Lambda 函数,该函数接收因接收来自 Kinesis 流的记录而触发的事件。该函数检索 Kinesis 有效负载,将 Base64 解码,并记录下记录内容。
- SDK适用于 Java 2.x
-
注意
还有更多相关信息 GitHub。在无服务器示例
存储库中查找完整示例,并了解如何进行设置和运行。 使用 Java 将 Kinesis 事件与 Lambda 结合使用。
// Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved. // SPDX-License-Identifier: Apache-2.0 package example; import com.amazonaws.services.lambda.runtime.Context; import com.amazonaws.services.lambda.runtime.LambdaLogger; import com.amazonaws.services.lambda.runtime.RequestHandler; import com.amazonaws.services.lambda.runtime.events.KinesisEvent; public class Handler implements RequestHandler<KinesisEvent, Void> { @Override public Void handleRequest(final KinesisEvent event, final Context context) { LambdaLogger logger = context.getLogger(); if (event.getRecords().isEmpty()) { logger.log("Empty Kinesis Event received"); return null; } for (KinesisEvent.KinesisEventRecord record : event.getRecords()) { try { logger.log("Processed Event with EventId: "+record.getEventID()); String data = new String(record.getKinesis().getData().array()); logger.log("Data:"+ data); // TODO: Do interesting work based on the new data } catch (Exception ex) { logger.log("An error occurred:"+ex.getMessage()); throw ex; } } logger.log("Successfully processed:"+event.getRecords().size()+" records"); return null; } }
以下代码示例展示了如何为接收来自 Kinesis 流的事件的 Lambda 函数实现部分批处理响应。该函数在响应中报告批处理项目失败,并指示 Lambda 稍后重试这些消息。
- SDK适用于 Java 2.x
-
注意
还有更多相关信息 GitHub。在无服务器示例
存储库中查找完整示例,并了解如何进行设置和运行。 报告使用 Java 进行 Lambda Kinesis 批处理项目失败。
// Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved. // SPDX-License-Identifier: Apache-2.0 import com.amazonaws.services.lambda.runtime.Context; import com.amazonaws.services.lambda.runtime.RequestHandler; import com.amazonaws.services.lambda.runtime.events.KinesisEvent; import com.amazonaws.services.lambda.runtime.events.StreamsEventResponse; import java.io.Serializable; import java.util.ArrayList; import java.util.List; public class ProcessKinesisRecords implements RequestHandler<KinesisEvent, StreamsEventResponse> { @Override public StreamsEventResponse handleRequest(KinesisEvent input, Context context) { List<StreamsEventResponse.BatchItemFailure> batchItemFailures = new ArrayList<>(); String curRecordSequenceNumber = ""; for (KinesisEvent.KinesisEventRecord kinesisEventRecord : input.getRecords()) { try { //Process your record KinesisEvent.Record kinesisRecord = kinesisEventRecord.getKinesis(); curRecordSequenceNumber = kinesisRecord.getSequenceNumber(); } catch (Exception e) { /* Since we are working with streams, we can return the failed item immediately. Lambda will immediately begin to retry processing from this failed item onwards. */ batchItemFailures.add(new StreamsEventResponse.BatchItemFailure(curRecordSequenceNumber)); return new StreamsEventResponse(batchItemFailures); } } return new StreamsEventResponse(batchItemFailures); } }