SDK for Java 2.x を使用した DynamoDB の例 - AWS SDK コード例

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SDK for Java 2.x を使用した DynamoDB の例

次のコード例は、DynamoDB AWS SDK for Java 2.x で を使用してアクションを実行し、一般的なシナリオを実装する方法を示しています。

アクションはより大きなプログラムからのコードの抜粋であり、コンテキスト内で実行する必要があります。アクションは個々のサービス機能を呼び出す方法を示していますが、関連するシナリオやサービス間の例ではアクションのコンテキストが確認できます。

「シナリオ」は、同じサービス内で複数の関数を呼び出して、特定のタスクを実行する方法を示すコード例です。

各例には、 へのリンクが含まれています。このリンクには GitHub、コンテキスト内でコードをセットアップして実行する方法の手順が記載されています。

開始方法

次のコード例は、DynamoDB の使用を開始する方法を示しています。

SDK for Java 2.x
注記

には他にもがあります GitHub。AWS コード例リポジトリ で全く同じ例を見つけて、設定と実行の方法を確認してください。

import software.amazon.awssdk.regions.Region; import software.amazon.awssdk.services.dynamodb.DynamoDbClient; import software.amazon.awssdk.services.dynamodb.model.DynamoDbException; import software.amazon.awssdk.services.dynamodb.model.ListTablesRequest; import software.amazon.awssdk.services.dynamodb.model.ListTablesResponse; 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 ListTables { public static void main(String[] args) { System.out.println("Listing your Amazon DynamoDB tables:\n"); Region region = Region.US_EAST_1; DynamoDbClient ddb = DynamoDbClient.builder() .region(region) .build(); listAllTables(ddb); ddb.close(); } public static void listAllTables(DynamoDbClient ddb) { boolean moreTables = true; String lastName = null; while (moreTables) { try { ListTablesResponse response = null; if (lastName == null) { ListTablesRequest request = ListTablesRequest.builder().build(); response = ddb.listTables(request); } else { ListTablesRequest request = ListTablesRequest.builder() .exclusiveStartTableName(lastName).build(); response = ddb.listTables(request); } List<String> tableNames = response.tableNames(); if (tableNames.size() > 0) { for (String curName : tableNames) { System.out.format("* %s\n", curName); } } else { System.out.println("No tables found!"); System.exit(0); } lastName = response.lastEvaluatedTableName(); if (lastName == null) { moreTables = false; } } catch (DynamoDbException e) { System.err.println(e.getMessage()); System.exit(1); } } System.out.println("\nDone!"); } }
  • API の詳細については、「 API リファレンスListTables」の「」を参照してください。 AWS SDK for Java 2.x

アクション

次の例は、BatchGetItem を使用する方法を説明しています。

SDK for Java 2.x
注記

には他にもがあります GitHub。AWS コード例リポジトリ で全く同じ例を見つけて、設定と実行の方法を確認してください。

サービスクライアントを使用してバッチアイテムを取得する方法を示します。

import software.amazon.awssdk.regions.Region; import software.amazon.awssdk.services.dynamodb.DynamoDbClient; import software.amazon.awssdk.services.dynamodb.model.AttributeValue; import software.amazon.awssdk.services.dynamodb.model.BatchGetItemRequest; import software.amazon.awssdk.services.dynamodb.model.BatchGetItemResponse; import software.amazon.awssdk.services.dynamodb.model.KeysAndAttributes; import java.util.HashMap; import java.util.List; import java.util.Map; /** * 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 BatchReadItems { public static void main(String[] args){ final String usage = """ Usage: <tableName> Where: tableName - The Amazon DynamoDB table (for example, Music).\s """; String tableName = "Music"; Region region = Region.US_EAST_1; DynamoDbClient dynamoDbClient = DynamoDbClient.builder() .region(region) .build(); getBatchItems(dynamoDbClient, tableName); } public static void getBatchItems(DynamoDbClient dynamoDbClient, String tableName) { // Define the primary key values for the items you want to retrieve. Map<String, AttributeValue> key1 = new HashMap<>(); key1.put("Artist", AttributeValue.builder().s("Artist1").build()); Map<String, AttributeValue> key2 = new HashMap<>(); key2.put("Artist", AttributeValue.builder().s("Artist2").build()); // Construct the batchGetItem request. Map<String, KeysAndAttributes> requestItems = new HashMap<>(); requestItems.put(tableName, KeysAndAttributes.builder() .keys(List.of(key1, key2)) .projectionExpression("Artist, SongTitle") .build()); BatchGetItemRequest batchGetItemRequest = BatchGetItemRequest.builder() .requestItems(requestItems) .build(); // Make the batchGetItem request. BatchGetItemResponse batchGetItemResponse = dynamoDbClient.batchGetItem(batchGetItemRequest); // Extract and print the retrieved items. Map<String, List<Map<String, AttributeValue>>> responses = batchGetItemResponse.responses(); if (responses.containsKey(tableName)) { List<Map<String, AttributeValue>> musicItems = responses.get(tableName); for (Map<String, AttributeValue> item : musicItems) { System.out.println("Artist: " + item.get("Artist").s() + ", SongTitle: " + item.get("SongTitle").s()); } } else { System.out.println("No items retrieved."); } } }

サービスクライアントおよびページネーターを使用してバッチアイテムを取得する方法を示します。

import software.amazon.awssdk.regions.Region; import software.amazon.awssdk.services.dynamodb.DynamoDbClient; import software.amazon.awssdk.services.dynamodb.model.AttributeValue; import software.amazon.awssdk.services.dynamodb.model.BatchGetItemRequest; import software.amazon.awssdk.services.dynamodb.model.KeysAndAttributes; import java.util.Collections; import java.util.HashMap; import java.util.List; import java.util.Map; public class BatchGetItemsPaginator { public static void main(String[] args){ final String usage = """ Usage: <tableName> Where: tableName - The Amazon DynamoDB table (for example, Music).\s """; String tableName = "Music"; Region region = Region.US_EAST_1; DynamoDbClient dynamoDbClient = DynamoDbClient.builder() .region(region) .build(); getBatchItemsPaginator(dynamoDbClient, tableName) ; } public static void getBatchItemsPaginator(DynamoDbClient dynamoDbClient, String tableName) { // Define the primary key values for the items you want to retrieve. Map<String, AttributeValue> key1 = new HashMap<>(); key1.put("Artist", AttributeValue.builder().s("Artist1").build()); Map<String, AttributeValue> key2 = new HashMap<>(); key2.put("Artist", AttributeValue.builder().s("Artist2").build()); // Construct the batchGetItem request. Map<String, KeysAndAttributes> requestItems = new HashMap<>(); requestItems.put(tableName, KeysAndAttributes.builder() .keys(List.of(key1, key2)) .projectionExpression("Artist, SongTitle") .build()); BatchGetItemRequest batchGetItemRequest = BatchGetItemRequest.builder() .requestItems(requestItems) .build(); // Use batchGetItemPaginator for paginated requests. dynamoDbClient.batchGetItemPaginator(batchGetItemRequest).stream() .flatMap(response -> response.responses().getOrDefault(tableName, Collections.emptyList()).stream()) .forEach(item -> { System.out.println("Artist: " + item.get("Artist").s() + ", SongTitle: " + item.get("SongTitle").s()); }); } }
  • API の詳細については、「 API リファレンスBatchGetItem」の「」を参照してください。 AWS SDK for Java 2.x

次の例は、BatchWriteItem を使用する方法を説明しています。

SDK for Java 2.x
注記

には他にもがあります GitHub。AWS コード例リポジトリ で全く同じ例を見つけて、設定と実行の方法を確認してください。

サービスクライアントを使用して、多数の項目をテーブルに挿入します。

import software.amazon.awssdk.regions.Region; import software.amazon.awssdk.services.dynamodb.DynamoDbClient; import software.amazon.awssdk.services.dynamodb.model.AttributeValue; import software.amazon.awssdk.services.dynamodb.model.BatchWriteItemRequest; import software.amazon.awssdk.services.dynamodb.model.BatchWriteItemResponse; import software.amazon.awssdk.services.dynamodb.model.DynamoDbException; import software.amazon.awssdk.services.dynamodb.model.PutRequest; import software.amazon.awssdk.services.dynamodb.model.WriteRequest; import java.util.ArrayList; import java.util.HashMap; import java.util.List; import java.util.Map; /** * 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 BatchWriteItems { public static void main(String[] args){ final String usage = """ Usage: <tableName> Where: tableName - The Amazon DynamoDB table (for example, Music).\s """; String tableName = "Music"; Region region = Region.US_EAST_1; DynamoDbClient dynamoDbClient = DynamoDbClient.builder() .region(region) .build(); addBatchItems(dynamoDbClient, tableName); } public static void addBatchItems(DynamoDbClient dynamoDbClient, String tableName) { // Specify the updates you want to perform. List<WriteRequest> writeRequests = new ArrayList<>(); // Set item 1. Map<String, AttributeValue> item1Attributes = new HashMap<>(); item1Attributes.put("Artist", AttributeValue.builder().s("Artist1").build()); item1Attributes.put("Rating", AttributeValue.builder().s("5").build()); item1Attributes.put("Comments", AttributeValue.builder().s("Great song!").build()); item1Attributes.put("SongTitle", AttributeValue.builder().s("SongTitle1").build()); writeRequests.add(WriteRequest.builder().putRequest(PutRequest.builder().item(item1Attributes).build()).build()); // Set item 2. Map<String, AttributeValue> item2Attributes = new HashMap<>(); item2Attributes.put("Artist", AttributeValue.builder().s("Artist2").build()); item2Attributes.put("Rating", AttributeValue.builder().s("4").build()); item2Attributes.put("Comments", AttributeValue.builder().s("Nice melody.").build()); item2Attributes.put("SongTitle", AttributeValue.builder().s("SongTitle2").build()); writeRequests.add(WriteRequest.builder().putRequest(PutRequest.builder().item(item2Attributes).build()).build()); try { // Create the BatchWriteItemRequest. BatchWriteItemRequest batchWriteItemRequest = BatchWriteItemRequest.builder() .requestItems(Map.of(tableName, writeRequests)) .build(); // Execute the BatchWriteItem operation. BatchWriteItemResponse batchWriteItemResponse = dynamoDbClient.batchWriteItem(batchWriteItemRequest); // Process the response. System.out.println("Batch write successful: " + batchWriteItemResponse); } catch (DynamoDbException e) { System.err.println(e.getMessage()); System.exit(1); } } }

拡張クライアントを使用して、多数の項目をテーブルに挿入します。

import com.example.dynamodb.Customer; import com.example.dynamodb.Music; import software.amazon.awssdk.enhanced.dynamodb.DynamoDbEnhancedClient; import software.amazon.awssdk.enhanced.dynamodb.DynamoDbTable; import software.amazon.awssdk.enhanced.dynamodb.Key; import software.amazon.awssdk.enhanced.dynamodb.TableSchema; import software.amazon.awssdk.enhanced.dynamodb.model.BatchWriteItemEnhancedRequest; import software.amazon.awssdk.enhanced.dynamodb.model.WriteBatch; import software.amazon.awssdk.regions.Region; import software.amazon.awssdk.services.dynamodb.DynamoDbClient; import software.amazon.awssdk.services.dynamodb.model.DynamoDbException; import java.time.Instant; import java.time.LocalDate; import java.time.LocalDateTime; import java.time.ZoneOffset; /* * Before running this code example, create an Amazon DynamoDB table named Customer with these columns: * - id - the id of the record that is the key * - custName - the customer name * - email - the email value * - registrationDate - an instant value when the item was added to the table * * Also, ensure that you have set up your development environment, including your credentials. * * For information, see this documentation topic: * * https://docs.aws.amazon.com/sdk-for-java/latest/developer-guide/get-started.html */ public class EnhancedBatchWriteItems { public static void main(String[] args) { Region region = Region.US_EAST_1; DynamoDbClient ddb = DynamoDbClient.builder() .region(region) .build(); DynamoDbEnhancedClient enhancedClient = DynamoDbEnhancedClient.builder() .dynamoDbClient(ddb) .build(); putBatchRecords(enhancedClient); ddb.close(); } public static void putBatchRecords(DynamoDbEnhancedClient enhancedClient) { try { DynamoDbTable<Customer> customerMappedTable = enhancedClient.table("Customer", TableSchema.fromBean(Customer.class)); DynamoDbTable<Music> musicMappedTable = enhancedClient.table("Music", TableSchema.fromBean(Music.class)); LocalDate localDate = LocalDate.parse("2020-04-07"); LocalDateTime localDateTime = localDate.atStartOfDay(); Instant instant = localDateTime.toInstant(ZoneOffset.UTC); Customer record2 = new Customer(); record2.setCustName("Fred Pink"); record2.setId("id110"); record2.setEmail("fredp@noserver.com"); record2.setRegistrationDate(instant); Customer record3 = new Customer(); record3.setCustName("Susan Pink"); record3.setId("id120"); record3.setEmail("spink@noserver.com"); record3.setRegistrationDate(instant); Customer record4 = new Customer(); record4.setCustName("Jerry orange"); record4.setId("id101"); record4.setEmail("jorange@noserver.com"); record4.setRegistrationDate(instant); BatchWriteItemEnhancedRequest batchWriteItemEnhancedRequest = BatchWriteItemEnhancedRequest .builder() .writeBatches( WriteBatch.builder(Customer.class) // add items to the Customer // table .mappedTableResource(customerMappedTable) .addPutItem(builder -> builder.item(record2)) .addPutItem(builder -> builder.item(record3)) .addPutItem(builder -> builder.item(record4)) .build(), WriteBatch.builder(Music.class) // delete an item from the Music // table .mappedTableResource(musicMappedTable) .addDeleteItem(builder -> builder.key( Key.builder().partitionValue( "Famous Band") .build())) .build()) .build(); // Add three items to the Customer table and delete one item from the Music // table. enhancedClient.batchWriteItem(batchWriteItemEnhancedRequest); System.out.println("done"); } catch (DynamoDbException e) { System.err.println(e.getMessage()); System.exit(1); } } }
  • API の詳細については、「 API リファレンスBatchWriteItem」の「」を参照してください。 AWS SDK for Java 2.x

次の例は、CreateTable を使用する方法を説明しています。

SDK for Java 2.x
注記

には他にもがあります GitHub。AWS コード例リポジトリ で全く同じ例を見つけて、設定と実行の方法を確認してください。

import software.amazon.awssdk.core.waiters.WaiterResponse; import software.amazon.awssdk.regions.Region; import software.amazon.awssdk.services.dynamodb.DynamoDbClient; import software.amazon.awssdk.services.dynamodb.model.AttributeDefinition; import software.amazon.awssdk.services.dynamodb.model.CreateTableRequest; import software.amazon.awssdk.services.dynamodb.model.CreateTableResponse; import software.amazon.awssdk.services.dynamodb.model.DescribeTableRequest; import software.amazon.awssdk.services.dynamodb.model.DescribeTableResponse; import software.amazon.awssdk.services.dynamodb.model.DynamoDbException; import software.amazon.awssdk.services.dynamodb.model.KeySchemaElement; import software.amazon.awssdk.services.dynamodb.model.KeyType; import software.amazon.awssdk.services.dynamodb.model.ProvisionedThroughput; import software.amazon.awssdk.services.dynamodb.model.ScalarAttributeType; import software.amazon.awssdk.services.dynamodb.waiters.DynamoDbWaiter; /** * 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 CreateTable { public static void main(String[] args) { final String usage = """ Usage: <tableName> <key> Where: tableName - The Amazon DynamoDB table to create (for example, Music3). key - The key for the Amazon DynamoDB table (for example, Artist). """; if (args.length != 2) { System.out.println(usage); System.exit(1); } String tableName = args[0]; String key = args[1]; System.out.println("Creating an Amazon DynamoDB table " + tableName + " with a simple primary key: " + key); Region region = Region.US_EAST_1; DynamoDbClient ddb = DynamoDbClient.builder() .region(region) .build(); String result = createTable(ddb, tableName, key); System.out.println("New table is " + result); ddb.close(); } public static String createTable(DynamoDbClient ddb, String tableName, String key) { DynamoDbWaiter dbWaiter = ddb.waiter(); CreateTableRequest request = CreateTableRequest.builder() .attributeDefinitions(AttributeDefinition.builder() .attributeName(key) .attributeType(ScalarAttributeType.S) .build()) .keySchema(KeySchemaElement.builder() .attributeName(key) .keyType(KeyType.HASH) .build()) .provisionedThroughput(ProvisionedThroughput.builder() .readCapacityUnits(10L) .writeCapacityUnits(10L) .build()) .tableName(tableName) .build(); String newTable; try { CreateTableResponse response = ddb.createTable(request); DescribeTableRequest tableRequest = DescribeTableRequest.builder() .tableName(tableName) .build(); // Wait until the Amazon DynamoDB table is created. WaiterResponse<DescribeTableResponse> waiterResponse = dbWaiter.waitUntilTableExists(tableRequest); waiterResponse.matched().response().ifPresent(System.out::println); newTable = response.tableDescription().tableName(); return newTable; } catch (DynamoDbException e) { System.err.println(e.getMessage()); System.exit(1); } return ""; } }
  • API の詳細については、「 API リファレンスCreateTable」の「」を参照してください。 AWS SDK for Java 2.x

次の例は、DeleteItem を使用する方法を説明しています。

SDK for Java 2.x
注記

には他にもがあります GitHub。AWS コード例リポジトリ で全く同じ例を見つけて、設定と実行の方法を確認してください。

import software.amazon.awssdk.regions.Region; import software.amazon.awssdk.services.dynamodb.DynamoDbClient; import software.amazon.awssdk.services.dynamodb.model.AttributeValue; import software.amazon.awssdk.services.dynamodb.model.DeleteItemRequest; import software.amazon.awssdk.services.dynamodb.model.DynamoDbException; import java.util.HashMap; /** * 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 DeleteItem { public static void main(String[] args) { final String usage = """ Usage: <tableName> <key> <keyval> Where: tableName - The Amazon DynamoDB table to delete the item from (for example, Music3). key - The key used in the Amazon DynamoDB table (for example, Artist).\s keyval - The key value that represents the item to delete (for example, Famous Band). """; if (args.length != 3) { System.out.println(usage); System.exit(1); } String tableName = args[0]; String key = args[1]; String keyVal = args[2]; System.out.format("Deleting item \"%s\" from %s\n", keyVal, tableName); Region region = Region.US_EAST_1; DynamoDbClient ddb = DynamoDbClient.builder() .region(region) .build(); deleteDynamoDBItem(ddb, tableName, key, keyVal); ddb.close(); } public static void deleteDynamoDBItem(DynamoDbClient ddb, String tableName, String key, String keyVal) { HashMap<String, AttributeValue> keyToGet = new HashMap<>(); keyToGet.put(key, AttributeValue.builder() .s(keyVal) .build()); DeleteItemRequest deleteReq = DeleteItemRequest.builder() .tableName(tableName) .key(keyToGet) .build(); try { ddb.deleteItem(deleteReq); } catch (DynamoDbException e) { System.err.println(e.getMessage()); System.exit(1); } } }
  • API の詳細については、「 API リファレンスDeleteItem」の「」を参照してください。 AWS SDK for Java 2.x

次の例は、DeleteTable を使用する方法を説明しています。

SDK for Java 2.x
注記

には他にもがあります GitHub。AWS コード例リポジトリ で全く同じ例を見つけて、設定と実行の方法を確認してください。

import software.amazon.awssdk.regions.Region; import software.amazon.awssdk.services.dynamodb.model.DynamoDbException; import software.amazon.awssdk.services.dynamodb.DynamoDbClient; import software.amazon.awssdk.services.dynamodb.model.DeleteTableRequest; /** * 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 DeleteTable { public static void main(String[] args) { final String usage = """ Usage: <tableName> Where: tableName - The Amazon DynamoDB table to delete (for example, Music3). **Warning** This program will delete the table that you specify! """; if (args.length != 1) { System.out.println(usage); System.exit(1); } String tableName = args[0]; System.out.format("Deleting the Amazon DynamoDB table %s...\n", tableName); Region region = Region.US_EAST_1; DynamoDbClient ddb = DynamoDbClient.builder() .region(region) .build(); deleteDynamoDBTable(ddb, tableName); ddb.close(); } public static void deleteDynamoDBTable(DynamoDbClient ddb, String tableName) { DeleteTableRequest request = DeleteTableRequest.builder() .tableName(tableName) .build(); try { ddb.deleteTable(request); } catch (DynamoDbException e) { System.err.println(e.getMessage()); System.exit(1); } System.out.println(tableName + " was successfully deleted!"); } }
  • API の詳細については、「 API リファレンスDeleteTable」の「」を参照してください。 AWS SDK for Java 2.x

次の例は、DescribeTable を使用する方法を説明しています。

SDK for Java 2.x
注記

には他にもがあります GitHub。AWS コード例リポジトリ で全く同じ例を見つけて、設定と実行の方法を確認してください。

import software.amazon.awssdk.regions.Region; import software.amazon.awssdk.services.dynamodb.model.DynamoDbException; import software.amazon.awssdk.services.dynamodb.DynamoDbClient; import software.amazon.awssdk.services.dynamodb.model.AttributeDefinition; import software.amazon.awssdk.services.dynamodb.model.DescribeTableRequest; import software.amazon.awssdk.services.dynamodb.model.ProvisionedThroughputDescription; import software.amazon.awssdk.services.dynamodb.model.TableDescription; 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 DescribeTable { public static void main(String[] args) { final String usage = """ Usage: <tableName> Where: tableName - The Amazon DynamoDB table to get information about (for example, Music3). """; if (args.length != 1) { System.out.println(usage); System.exit(1); } String tableName = args[0]; System.out.format("Getting description for %s\n\n", tableName); Region region = Region.US_EAST_1; DynamoDbClient ddb = DynamoDbClient.builder() .region(region) .build(); describeDymamoDBTable(ddb, tableName); ddb.close(); } public static void describeDymamoDBTable(DynamoDbClient ddb, String tableName) { DescribeTableRequest request = DescribeTableRequest.builder() .tableName(tableName) .build(); try { TableDescription tableInfo = ddb.describeTable(request).table(); if (tableInfo != null) { System.out.format("Table name : %s\n", tableInfo.tableName()); System.out.format("Table ARN : %s\n", tableInfo.tableArn()); System.out.format("Status : %s\n", tableInfo.tableStatus()); System.out.format("Item count : %d\n", tableInfo.itemCount()); System.out.format("Size (bytes): %d\n", tableInfo.tableSizeBytes()); ProvisionedThroughputDescription throughputInfo = tableInfo.provisionedThroughput(); System.out.println("Throughput"); System.out.format(" Read Capacity : %d\n", throughputInfo.readCapacityUnits()); System.out.format(" Write Capacity: %d\n", throughputInfo.writeCapacityUnits()); List<AttributeDefinition> attributes = tableInfo.attributeDefinitions(); System.out.println("Attributes"); for (AttributeDefinition a : attributes) { System.out.format(" %s (%s)\n", a.attributeName(), a.attributeType()); } } } catch (DynamoDbException e) { System.err.println(e.getMessage()); System.exit(1); } System.out.println("\nDone!"); } }
  • API の詳細については、「 API リファレンスDescribeTable」の「」を参照してください。 AWS SDK for Java 2.x

次の例は、GetItem を使用する方法を説明しています。

SDK for Java 2.x
注記

には他にもがあります GitHub。AWS コード例リポジトリ で全く同じ例を見つけて、設定と実行の方法を確認してください。

を使用して、テーブルから項目を取得します DynamoDbClient。

import software.amazon.awssdk.regions.Region; import software.amazon.awssdk.services.dynamodb.model.DynamoDbException; import software.amazon.awssdk.services.dynamodb.DynamoDbClient; import software.amazon.awssdk.services.dynamodb.model.AttributeValue; import software.amazon.awssdk.services.dynamodb.model.GetItemRequest; import java.util.HashMap; import java.util.Map; import java.util.Set; /** * 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 * * To get an item from an Amazon DynamoDB table using the AWS SDK for Java V2, * its better practice to use the * Enhanced Client, see the EnhancedGetItem example. */ public class GetItem { public static void main(String[] args) { final String usage = """ Usage: <tableName> <key> <keyVal> Where: tableName - The Amazon DynamoDB table from which an item is retrieved (for example, Music3).\s key - The key used in the Amazon DynamoDB table (for example, Artist).\s keyval - The key value that represents the item to get (for example, Famous Band). """; if (args.length != 3) { System.out.println(usage); System.exit(1); } String tableName = args[0]; String key = args[1]; String keyVal = args[2]; System.out.format("Retrieving item \"%s\" from \"%s\"\n", keyVal, tableName); Region region = Region.US_EAST_1; DynamoDbClient ddb = DynamoDbClient.builder() .region(region) .build(); getDynamoDBItem(ddb, tableName, key, keyVal); ddb.close(); } public static void getDynamoDBItem(DynamoDbClient ddb, String tableName, String key, String keyVal) { HashMap<String, AttributeValue> keyToGet = new HashMap<>(); keyToGet.put(key, AttributeValue.builder() .s(keyVal) .build()); GetItemRequest request = GetItemRequest.builder() .key(keyToGet) .tableName(tableName) .build(); try { // If there is no matching item, GetItem does not return any data. Map<String, AttributeValue> returnedItem = ddb.getItem(request).item(); if (returnedItem.isEmpty()) System.out.format("No item found with the key %s!\n", key); else { Set<String> keys = returnedItem.keySet(); System.out.println("Amazon DynamoDB table attributes: \n"); for (String key1 : keys) { System.out.format("%s: %s\n", key1, returnedItem.get(key1).toString()); } } } catch (DynamoDbException e) { System.err.println(e.getMessage()); System.exit(1); } } }
  • API の詳細については、「 API リファレンスGetItem」の「」を参照してください。 AWS SDK for Java 2.x

次の例は、ListTables を使用する方法を説明しています。

SDK for Java 2.x
注記

には他にもがあります GitHub。AWS コード例リポジトリ で全く同じ例を見つけて、設定と実行の方法を確認してください。

import software.amazon.awssdk.regions.Region; import software.amazon.awssdk.services.dynamodb.DynamoDbClient; import software.amazon.awssdk.services.dynamodb.model.DynamoDbException; import software.amazon.awssdk.services.dynamodb.model.ListTablesRequest; import software.amazon.awssdk.services.dynamodb.model.ListTablesResponse; 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 ListTables { public static void main(String[] args) { System.out.println("Listing your Amazon DynamoDB tables:\n"); Region region = Region.US_EAST_1; DynamoDbClient ddb = DynamoDbClient.builder() .region(region) .build(); listAllTables(ddb); ddb.close(); } public static void listAllTables(DynamoDbClient ddb) { boolean moreTables = true; String lastName = null; while (moreTables) { try { ListTablesResponse response = null; if (lastName == null) { ListTablesRequest request = ListTablesRequest.builder().build(); response = ddb.listTables(request); } else { ListTablesRequest request = ListTablesRequest.builder() .exclusiveStartTableName(lastName).build(); response = ddb.listTables(request); } List<String> tableNames = response.tableNames(); if (tableNames.size() > 0) { for (String curName : tableNames) { System.out.format("* %s\n", curName); } } else { System.out.println("No tables found!"); System.exit(0); } lastName = response.lastEvaluatedTableName(); if (lastName == null) { moreTables = false; } } catch (DynamoDbException e) { System.err.println(e.getMessage()); System.exit(1); } } System.out.println("\nDone!"); } }
  • API の詳細については、「 API リファレンスListTables」の「」を参照してください。 AWS SDK for Java 2.x

次の例は、PutItem を使用する方法を説明しています。

SDK for Java 2.x
注記

には他にもがあります GitHub。AWS コード例リポジトリ で全く同じ例を見つけて、設定と実行の方法を確認してください。

を使用してテーブルに項目を配置しますDynamoDbClient

import software.amazon.awssdk.regions.Region; import software.amazon.awssdk.services.dynamodb.DynamoDbClient; import software.amazon.awssdk.services.dynamodb.model.AttributeValue; import software.amazon.awssdk.services.dynamodb.model.DynamoDbException; import software.amazon.awssdk.services.dynamodb.model.PutItemRequest; import software.amazon.awssdk.services.dynamodb.model.PutItemResponse; import software.amazon.awssdk.services.dynamodb.model.ResourceNotFoundException; import java.util.HashMap; /** * 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 * * To place items into an Amazon DynamoDB table using the AWS SDK for Java V2, * its better practice to use the * Enhanced Client. See the EnhancedPutItem example. */ public class PutItem { public static void main(String[] args) { final String usage = """ Usage: <tableName> <key> <keyVal> <albumtitle> <albumtitleval> <awards> <awardsval> <Songtitle> <songtitleval> Where: tableName - The Amazon DynamoDB table in which an item is placed (for example, Music3). key - The key used in the Amazon DynamoDB table (for example, Artist). keyval - The key value that represents the item to get (for example, Famous Band). albumTitle - The Album title (for example, AlbumTitle). AlbumTitleValue - The name of the album (for example, Songs About Life ). Awards - The awards column (for example, Awards). AwardVal - The value of the awards (for example, 10). SongTitle - The song title (for example, SongTitle). SongTitleVal - The value of the song title (for example, Happy Day). **Warning** This program will place an item that you specify into a table! """; if (args.length != 9) { System.out.println(usage); System.exit(1); } String tableName = args[0]; String key = args[1]; String keyVal = args[2]; String albumTitle = args[3]; String albumTitleValue = args[4]; String awards = args[5]; String awardVal = args[6]; String songTitle = args[7]; String songTitleVal = args[8]; Region region = Region.US_EAST_1; DynamoDbClient ddb = DynamoDbClient.builder() .region(region) .build(); putItemInTable(ddb, tableName, key, keyVal, albumTitle, albumTitleValue, awards, awardVal, songTitle, songTitleVal); System.out.println("Done!"); ddb.close(); } public static void putItemInTable(DynamoDbClient ddb, String tableName, String key, String keyVal, String albumTitle, String albumTitleValue, String awards, String awardVal, String songTitle, String songTitleVal) { HashMap<String, AttributeValue> itemValues = new HashMap<>(); itemValues.put(key, AttributeValue.builder().s(keyVal).build()); itemValues.put(songTitle, AttributeValue.builder().s(songTitleVal).build()); itemValues.put(albumTitle, AttributeValue.builder().s(albumTitleValue).build()); itemValues.put(awards, AttributeValue.builder().s(awardVal).build()); PutItemRequest request = PutItemRequest.builder() .tableName(tableName) .item(itemValues) .build(); try { PutItemResponse response = ddb.putItem(request); System.out.println(tableName + " was successfully updated. The request id is " + response.responseMetadata().requestId()); } catch (ResourceNotFoundException e) { System.err.format("Error: The Amazon DynamoDB table \"%s\" can't be found.\n", tableName); System.err.println("Be sure that it exists and that you've typed its name correctly!"); System.exit(1); } catch (DynamoDbException e) { System.err.println(e.getMessage()); System.exit(1); } } }
  • API の詳細については、「 API リファレンスPutItem」の「」を参照してください。 AWS SDK for Java 2.x

次の例は、Query を使用する方法を説明しています。

SDK for Java 2.x
注記

には他にもがあります GitHub。AWS コード例リポジトリ で全く同じ例を見つけて、設定と実行の方法を確認してください。

を使用してテーブルにクエリを実行しますDynamoDbClient

import software.amazon.awssdk.regions.Region; import software.amazon.awssdk.services.dynamodb.DynamoDbClient; import software.amazon.awssdk.services.dynamodb.model.AttributeValue; import software.amazon.awssdk.services.dynamodb.model.DynamoDbException; import software.amazon.awssdk.services.dynamodb.model.QueryRequest; import software.amazon.awssdk.services.dynamodb.model.QueryResponse; import java.util.HashMap; /** * 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 * * To query items from an Amazon DynamoDB table using the AWS SDK for Java V2, * its better practice to use the * Enhanced Client. See the EnhancedQueryRecords example. */ public class Query { public static void main(String[] args) { final String usage = """ Usage: <tableName> <partitionKeyName> <partitionKeyVal> Where: tableName - The Amazon DynamoDB table to put the item in (for example, Music3). partitionKeyName - The partition key name of the Amazon DynamoDB table (for example, Artist). partitionKeyVal - The value of the partition key that should match (for example, Famous Band). """; if (args.length != 3) { System.out.println(usage); System.exit(1); } String tableName = args[0]; String partitionKeyName = args[1]; String partitionKeyVal = args[2]; // For more information about an alias, see: // https://docs.aws.amazon.com/amazondynamodb/latest/developerguide/Expressions.ExpressionAttributeNames.html String partitionAlias = "#a"; System.out.format("Querying %s", tableName); System.out.println(""); Region region = Region.US_EAST_1; DynamoDbClient ddb = DynamoDbClient.builder() .region(region) .build(); int count = queryTable(ddb, tableName, partitionKeyName, partitionKeyVal, partitionAlias); System.out.println("There were " + count + " record(s) returned"); ddb.close(); } public static int queryTable(DynamoDbClient ddb, String tableName, String partitionKeyName, String partitionKeyVal, String partitionAlias) { // Set up an alias for the partition key name in case it's a reserved word. HashMap<String, String> attrNameAlias = new HashMap<String, String>(); attrNameAlias.put(partitionAlias, partitionKeyName); // Set up mapping of the partition name with the value. HashMap<String, AttributeValue> attrValues = new HashMap<>(); attrValues.put(":" + partitionKeyName, AttributeValue.builder() .s(partitionKeyVal) .build()); QueryRequest queryReq = QueryRequest.builder() .tableName(tableName) .keyConditionExpression(partitionAlias + " = :" + partitionKeyName) .expressionAttributeNames(attrNameAlias) .expressionAttributeValues(attrValues) .build(); try { QueryResponse response = ddb.query(queryReq); return response.count(); } catch (DynamoDbException e) { System.err.println(e.getMessage()); System.exit(1); } return -1; } }

DynamoDbClient とセカンダリインデックスを使用してテーブルに対してクエリを実行します。

import software.amazon.awssdk.regions.Region; import software.amazon.awssdk.services.dynamodb.DynamoDbClient; import software.amazon.awssdk.services.dynamodb.model.AttributeValue; import software.amazon.awssdk.services.dynamodb.model.DynamoDbException; import software.amazon.awssdk.services.dynamodb.model.QueryRequest; import software.amazon.awssdk.services.dynamodb.model.QueryResponse; import java.util.HashMap; import java.util.Map; /** * 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 * * Create the Movies table by running the Scenario example and loading the Movie * data from the JSON file. Next create a secondary * index for the Movies table that uses only the year column. Name the index * **year-index**. For more information, see: * * https://docs.aws.amazon.com/amazondynamodb/latest/developerguide/GSI.html */ public class QueryItemsUsingIndex { public static void main(String[] args) { String tableName = "Movies"; Region region = Region.US_EAST_1; DynamoDbClient ddb = DynamoDbClient.builder() .region(region) .build(); queryIndex(ddb, tableName); ddb.close(); } public static void queryIndex(DynamoDbClient ddb, String tableName) { try { Map<String, String> expressionAttributesNames = new HashMap<>(); expressionAttributesNames.put("#year", "year"); Map<String, AttributeValue> expressionAttributeValues = new HashMap<>(); expressionAttributeValues.put(":yearValue", AttributeValue.builder().n("2013").build()); QueryRequest request = QueryRequest.builder() .tableName(tableName) .indexName("year-index") .keyConditionExpression("#year = :yearValue") .expressionAttributeNames(expressionAttributesNames) .expressionAttributeValues(expressionAttributeValues) .build(); System.out.println("=== Movie Titles ==="); QueryResponse response = ddb.query(request); response.items() .forEach(movie -> System.out.println(movie.get("title").s())); } catch (DynamoDbException e) { System.err.println(e.getMessage()); System.exit(1); } } }
  • API の詳細については、「AWS SDK for Java 2.x API リファレンス」の「Query」を参照してください。

次の例は、Scan を使用する方法を説明しています。

SDK for Java 2.x
注記

には他にもがあります GitHub。AWS コード例リポジトリ で全く同じ例を見つけて、設定と実行の方法を確認してください。

を使用して Amazon DynamoDB テーブルをスキャンしますDynamoDbClient

import software.amazon.awssdk.regions.Region; import software.amazon.awssdk.services.dynamodb.DynamoDbClient; import software.amazon.awssdk.services.dynamodb.model.AttributeValue; import software.amazon.awssdk.services.dynamodb.model.DynamoDbException; import software.amazon.awssdk.services.dynamodb.model.ScanRequest; import software.amazon.awssdk.services.dynamodb.model.ScanResponse; import java.util.Map; import java.util.Set; /** * 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 * * To scan items from an Amazon DynamoDB table using the AWS SDK for Java V2, * its better practice to use the * Enhanced Client, See the EnhancedScanRecords example. */ public class DynamoDBScanItems { public static void main(String[] args) { final String usage = """ Usage: <tableName> Where: tableName - The Amazon DynamoDB table to get information from (for example, Music3). """; if (args.length != 1) { System.out.println(usage); System.exit(1); } String tableName = args[0]; Region region = Region.US_EAST_1; DynamoDbClient ddb = DynamoDbClient.builder() .region(region) .build(); scanItems(ddb, tableName); ddb.close(); } public static void scanItems(DynamoDbClient ddb, String tableName) { try { ScanRequest scanRequest = ScanRequest.builder() .tableName(tableName) .build(); ScanResponse response = ddb.scan(scanRequest); for (Map<String, AttributeValue> item : response.items()) { Set<String> keys = item.keySet(); for (String key : keys) { System.out.println("The key name is " + key + "\n"); System.out.println("The value is " + item.get(key).s()); } } } catch (DynamoDbException e) { e.printStackTrace(); System.exit(1); } } }
  • API の詳細については、「AWS SDK for Java 2.x API リファレンス」の「Scan」を参照してください。

次の例は、UpdateItem を使用する方法を説明しています。

SDK for Java 2.x
注記

には他にもがあります GitHub。AWS コード例リポジトリ で全く同じ例を見つけて、設定と実行の方法を確認してください。

を使用してテーブル内の項目を更新しますDynamoDbClient

import software.amazon.awssdk.regions.Region; import software.amazon.awssdk.services.dynamodb.model.DynamoDbException; import software.amazon.awssdk.services.dynamodb.model.AttributeAction; import software.amazon.awssdk.services.dynamodb.model.AttributeValue; import software.amazon.awssdk.services.dynamodb.model.AttributeValueUpdate; import software.amazon.awssdk.services.dynamodb.model.UpdateItemRequest; import software.amazon.awssdk.services.dynamodb.DynamoDbClient; import java.util.HashMap; /** * 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 * * To update an Amazon DynamoDB table using the AWS SDK for Java V2, its better * practice to use the * Enhanced Client, See the EnhancedModifyItem example. */ public class UpdateItem { public static void main(String[] args) { final String usage = """ Usage: <tableName> <key> <keyVal> <name> <updateVal> Where: tableName - The Amazon DynamoDB table (for example, Music3). key - The name of the key in the table (for example, Artist). keyVal - The value of the key (for example, Famous Band). name - The name of the column where the value is updated (for example, Awards). updateVal - The value used to update an item (for example, 14). Example: UpdateItem Music3 Artist Famous Band Awards 14 """; if (args.length != 5) { System.out.println(usage); System.exit(1); } String tableName = args[0]; String key = args[1]; String keyVal = args[2]; String name = args[3]; String updateVal = args[4]; Region region = Region.US_EAST_1; DynamoDbClient ddb = DynamoDbClient.builder() .region(region) .build(); updateTableItem(ddb, tableName, key, keyVal, name, updateVal); ddb.close(); } public static void updateTableItem(DynamoDbClient ddb, String tableName, String key, String keyVal, String name, String updateVal) { HashMap<String, AttributeValue> itemKey = new HashMap<>(); itemKey.put(key, AttributeValue.builder() .s(keyVal) .build()); HashMap<String, AttributeValueUpdate> updatedValues = new HashMap<>(); updatedValues.put(name, AttributeValueUpdate.builder() .value(AttributeValue.builder().s(updateVal).build()) .action(AttributeAction.PUT) .build()); UpdateItemRequest request = UpdateItemRequest.builder() .tableName(tableName) .key(itemKey) .attributeUpdates(updatedValues) .build(); try { ddb.updateItem(request); } catch (DynamoDbException e) { System.err.println(e.getMessage()); System.exit(1); } System.out.println("The Amazon DynamoDB table was updated!"); } }
  • API の詳細については、「 API リファレンスUpdateItem」の「」を参照してください。 AWS SDK for Java 2.x

シナリオ

次のコードサンプルは、以下の操作方法を示しています。

  • 映画データを保持できるテーブルを作成する。

  • テーブルに 1 つの映画を入れ、取得して更新する。

  • サンプル JSON ファイルから映画データをテーブルに書き込む。

  • 特定の年にリリースされた映画を照会する。

  • 何年もの間にリリースされた映画をスキャンする。

  • テーブルからムービーを削除し、テーブルを削除します。

SDK for Java 2.x
注記

には他にもがあります GitHub。AWS コード例リポジトリ で全く同じ例を見つけて、設定と実行の方法を確認してください。

DynamoDB テーブルを作成します。

// Create a table with a Sort key. public static void createTable(DynamoDbClient ddb, String tableName) { DynamoDbWaiter dbWaiter = ddb.waiter(); ArrayList<AttributeDefinition> attributeDefinitions = new ArrayList<>(); // Define attributes. attributeDefinitions.add(AttributeDefinition.builder() .attributeName("year") .attributeType("N") .build()); attributeDefinitions.add(AttributeDefinition.builder() .attributeName("title") .attributeType("S") .build()); ArrayList<KeySchemaElement> tableKey = new ArrayList<>(); KeySchemaElement key = KeySchemaElement.builder() .attributeName("year") .keyType(KeyType.HASH) .build(); KeySchemaElement key2 = KeySchemaElement.builder() .attributeName("title") .keyType(KeyType.RANGE) .build(); // Add KeySchemaElement objects to the list. tableKey.add(key); tableKey.add(key2); CreateTableRequest request = CreateTableRequest.builder() .keySchema(tableKey) .provisionedThroughput(ProvisionedThroughput.builder() .readCapacityUnits(10L) .writeCapacityUnits(10L) .build()) .attributeDefinitions(attributeDefinitions) .tableName(tableName) .build(); try { CreateTableResponse response = ddb.createTable(request); DescribeTableRequest tableRequest = DescribeTableRequest.builder() .tableName(tableName) .build(); // Wait until the Amazon DynamoDB table is created. WaiterResponse<DescribeTableResponse> waiterResponse = dbWaiter.waitUntilTableExists(tableRequest); waiterResponse.matched().response().ifPresent(System.out::println); String newTable = response.tableDescription().tableName(); System.out.println("The " + newTable + " was successfully created."); } catch (DynamoDbException e) { System.err.println(e.getMessage()); System.exit(1); } }

サンプルの JSON ファイルをダウンロードして抽出するヘルパー関数を作成します。

// Load data into the table. public static void loadData(DynamoDbClient ddb, String tableName, String fileName) throws IOException { DynamoDbEnhancedClient enhancedClient = DynamoDbEnhancedClient.builder() .dynamoDbClient(ddb) .build(); DynamoDbTable<Movies> mappedTable = enhancedClient.table("Movies", TableSchema.fromBean(Movies.class)); JsonParser parser = new JsonFactory().createParser(new File(fileName)); com.fasterxml.jackson.databind.JsonNode rootNode = new ObjectMapper().readTree(parser); Iterator<JsonNode> iter = rootNode.iterator(); ObjectNode currentNode; int t = 0; while (iter.hasNext()) { // Only add 200 Movies to the table. if (t == 200) break; currentNode = (ObjectNode) iter.next(); int year = currentNode.path("year").asInt(); String title = currentNode.path("title").asText(); String info = currentNode.path("info").toString(); Movies movies = new Movies(); movies.setYear(year); movies.setTitle(title); movies.setInfo(info); // Put the data into the Amazon DynamoDB Movie table. mappedTable.putItem(movies); t++; } }

テーブルから項目を取得します。

public static void getItem(DynamoDbClient ddb) { HashMap<String, AttributeValue> keyToGet = new HashMap<>(); keyToGet.put("year", AttributeValue.builder() .n("1933") .build()); keyToGet.put("title", AttributeValue.builder() .s("King Kong") .build()); GetItemRequest request = GetItemRequest.builder() .key(keyToGet) .tableName("Movies") .build(); try { Map<String, AttributeValue> returnedItem = ddb.getItem(request).item(); if (returnedItem != null) { Set<String> keys = returnedItem.keySet(); System.out.println("Amazon DynamoDB table attributes: \n"); for (String key1 : keys) { System.out.format("%s: %s\n", key1, returnedItem.get(key1).toString()); } } else { System.out.format("No item found with the key %s!\n", "year"); } } catch (DynamoDbException e) { System.err.println(e.getMessage()); System.exit(1); } }

完全な例です。

/** * 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 * * This Java example performs these tasks: * * 1. Creates the Amazon DynamoDB Movie table with partition and sort key. * 2. Puts data into the Amazon DynamoDB table from a JSON document using the * Enhanced client. * 3. Gets data from the Movie table. * 4. Adds a new item. * 5. Updates an item. * 6. Uses a Scan to query items using the Enhanced client. * 7. Queries all items where the year is 2013 using the Enhanced Client. * 8. Deletes the table. */ public class Scenario { public static final String DASHES = new String(new char[80]).replace("\0", "-"); public static void main(String[] args) throws IOException { final String usage = """ Usage: <fileName> Where: fileName - The path to the moviedata.json file that you can download from the Amazon DynamoDB Developer Guide. """; if (args.length != 1) { System.out.println(usage); System.exit(1); } String tableName = "Movies"; String fileName = args[0]; Region region = Region.US_EAST_1; DynamoDbClient ddb = DynamoDbClient.builder() .region(region) .build(); System.out.println(DASHES); System.out.println("Welcome to the Amazon DynamoDB example scenario."); System.out.println(DASHES); System.out.println(DASHES); System.out.println( "1. Creating an Amazon DynamoDB table named Movies with a key named year and a sort key named title."); createTable(ddb, tableName); System.out.println(DASHES); System.out.println(DASHES); System.out.println("2. Loading data into the Amazon DynamoDB table."); loadData(ddb, tableName, fileName); System.out.println(DASHES); System.out.println(DASHES); System.out.println("3. Getting data from the Movie table."); getItem(ddb); System.out.println(DASHES); System.out.println(DASHES); System.out.println("4. Putting a record into the Amazon DynamoDB table."); putRecord(ddb); System.out.println(DASHES); System.out.println(DASHES); System.out.println("5. Updating a record."); updateTableItem(ddb, tableName); System.out.println(DASHES); System.out.println(DASHES); System.out.println("6. Scanning the Amazon DynamoDB table."); scanMovies(ddb, tableName); System.out.println(DASHES); System.out.println(DASHES); System.out.println("7. Querying the Movies released in 2013."); queryTable(ddb); System.out.println(DASHES); System.out.println(DASHES); System.out.println("8. Deleting the Amazon DynamoDB table."); deleteDynamoDBTable(ddb, tableName); System.out.println(DASHES); ddb.close(); } // Create a table with a Sort key. public static void createTable(DynamoDbClient ddb, String tableName) { DynamoDbWaiter dbWaiter = ddb.waiter(); ArrayList<AttributeDefinition> attributeDefinitions = new ArrayList<>(); // Define attributes. attributeDefinitions.add(AttributeDefinition.builder() .attributeName("year") .attributeType("N") .build()); attributeDefinitions.add(AttributeDefinition.builder() .attributeName("title") .attributeType("S") .build()); ArrayList<KeySchemaElement> tableKey = new ArrayList<>(); KeySchemaElement key = KeySchemaElement.builder() .attributeName("year") .keyType(KeyType.HASH) .build(); KeySchemaElement key2 = KeySchemaElement.builder() .attributeName("title") .keyType(KeyType.RANGE) .build(); // Add KeySchemaElement objects to the list. tableKey.add(key); tableKey.add(key2); CreateTableRequest request = CreateTableRequest.builder() .keySchema(tableKey) .provisionedThroughput(ProvisionedThroughput.builder() .readCapacityUnits(10L) .writeCapacityUnits(10L) .build()) .attributeDefinitions(attributeDefinitions) .tableName(tableName) .build(); try { CreateTableResponse response = ddb.createTable(request); DescribeTableRequest tableRequest = DescribeTableRequest.builder() .tableName(tableName) .build(); // Wait until the Amazon DynamoDB table is created. WaiterResponse<DescribeTableResponse> waiterResponse = dbWaiter.waitUntilTableExists(tableRequest); waiterResponse.matched().response().ifPresent(System.out::println); String newTable = response.tableDescription().tableName(); System.out.println("The " + newTable + " was successfully created."); } catch (DynamoDbException e) { System.err.println(e.getMessage()); System.exit(1); } } // Query the table. public static void queryTable(DynamoDbClient ddb) { try { DynamoDbEnhancedClient enhancedClient = DynamoDbEnhancedClient.builder() .dynamoDbClient(ddb) .build(); DynamoDbTable<Movies> custTable = enhancedClient.table("Movies", TableSchema.fromBean(Movies.class)); QueryConditional queryConditional = QueryConditional .keyEqualTo(Key.builder() .partitionValue(2013) .build()); // Get items in the table and write out the ID value. Iterator<Movies> results = custTable.query(queryConditional).items().iterator(); String result = ""; while (results.hasNext()) { Movies rec = results.next(); System.out.println("The title of the movie is " + rec.getTitle()); System.out.println("The movie information is " + rec.getInfo()); } } catch (DynamoDbException e) { System.err.println(e.getMessage()); System.exit(1); } } // Scan the table. public static void scanMovies(DynamoDbClient ddb, String tableName) { System.out.println("******* Scanning all movies.\n"); try { DynamoDbEnhancedClient enhancedClient = DynamoDbEnhancedClient.builder() .dynamoDbClient(ddb) .build(); DynamoDbTable<Movies> custTable = enhancedClient.table("Movies", TableSchema.fromBean(Movies.class)); Iterator<Movies> results = custTable.scan().items().iterator(); while (results.hasNext()) { Movies rec = results.next(); System.out.println("The movie title is " + rec.getTitle()); System.out.println("The movie year is " + rec.getYear()); } } catch (DynamoDbException e) { System.err.println(e.getMessage()); System.exit(1); } } // Load data into the table. public static void loadData(DynamoDbClient ddb, String tableName, String fileName) throws IOException { DynamoDbEnhancedClient enhancedClient = DynamoDbEnhancedClient.builder() .dynamoDbClient(ddb) .build(); DynamoDbTable<Movies> mappedTable = enhancedClient.table("Movies", TableSchema.fromBean(Movies.class)); JsonParser parser = new JsonFactory().createParser(new File(fileName)); com.fasterxml.jackson.databind.JsonNode rootNode = new ObjectMapper().readTree(parser); Iterator<JsonNode> iter = rootNode.iterator(); ObjectNode currentNode; int t = 0; while (iter.hasNext()) { // Only add 200 Movies to the table. if (t == 200) break; currentNode = (ObjectNode) iter.next(); int year = currentNode.path("year").asInt(); String title = currentNode.path("title").asText(); String info = currentNode.path("info").toString(); Movies movies = new Movies(); movies.setYear(year); movies.setTitle(title); movies.setInfo(info); // Put the data into the Amazon DynamoDB Movie table. mappedTable.putItem(movies); t++; } } // Update the record to include show only directors. public static void updateTableItem(DynamoDbClient ddb, String tableName) { HashMap<String, AttributeValue> itemKey = new HashMap<>(); itemKey.put("year", AttributeValue.builder().n("1933").build()); itemKey.put("title", AttributeValue.builder().s("King Kong").build()); HashMap<String, AttributeValueUpdate> updatedValues = new HashMap<>(); updatedValues.put("info", AttributeValueUpdate.builder() .value(AttributeValue.builder().s("{\"directors\":[\"Merian C. Cooper\",\"Ernest B. Schoedsack\"]") .build()) .action(AttributeAction.PUT) .build()); UpdateItemRequest request = UpdateItemRequest.builder() .tableName(tableName) .key(itemKey) .attributeUpdates(updatedValues) .build(); try { ddb.updateItem(request); } catch (ResourceNotFoundException e) { System.err.println(e.getMessage()); System.exit(1); } catch (DynamoDbException e) { System.err.println(e.getMessage()); System.exit(1); } System.out.println("Item was updated!"); } public static void deleteDynamoDBTable(DynamoDbClient ddb, String tableName) { DeleteTableRequest request = DeleteTableRequest.builder() .tableName(tableName) .build(); try { ddb.deleteTable(request); } catch (DynamoDbException e) { System.err.println(e.getMessage()); System.exit(1); } System.out.println(tableName + " was successfully deleted!"); } public static void putRecord(DynamoDbClient ddb) { try { DynamoDbEnhancedClient enhancedClient = DynamoDbEnhancedClient.builder() .dynamoDbClient(ddb) .build(); DynamoDbTable<Movies> table = enhancedClient.table("Movies", TableSchema.fromBean(Movies.class)); // Populate the Table. Movies record = new Movies(); record.setYear(2020); record.setTitle("My Movie2"); record.setInfo("no info"); table.putItem(record); } catch (DynamoDbException e) { System.err.println(e.getMessage()); System.exit(1); } System.out.println("Added a new movie to the table."); } public static void getItem(DynamoDbClient ddb) { HashMap<String, AttributeValue> keyToGet = new HashMap<>(); keyToGet.put("year", AttributeValue.builder() .n("1933") .build()); keyToGet.put("title", AttributeValue.builder() .s("King Kong") .build()); GetItemRequest request = GetItemRequest.builder() .key(keyToGet) .tableName("Movies") .build(); try { Map<String, AttributeValue> returnedItem = ddb.getItem(request).item(); if (returnedItem != null) { Set<String> keys = returnedItem.keySet(); System.out.println("Amazon DynamoDB table attributes: \n"); for (String key1 : keys) { System.out.format("%s: %s\n", key1, returnedItem.get(key1).toString()); } } else { System.out.format("No item found with the key %s!\n", "year"); } } catch (DynamoDbException e) { System.err.println(e.getMessage()); System.exit(1); } } }

次のコードサンプルは、以下の操作方法を示しています。

  • 複数の SELECT ステートメントを実行して、項目のバッチを取得する。

  • 複数の INSERT ステートメントを実行して、項目のバッチを追加する。

  • 複数の UPDATE ステートメントを実行して、項目のバッチを更新する。

  • 複数の DELETE ステートメントを実行して、項目のバッチを削除する。

SDK for Java 2.x
注記

には他にもがあります GitHub。AWS コード例リポジトリ で全く同じ例を見つけて、設定と実行の方法を確認してください。

public class ScenarioPartiQLBatch { public static void main(String[] args) throws IOException { String tableName = "MoviesPartiQBatch"; Region region = Region.US_EAST_1; DynamoDbClient ddb = DynamoDbClient.builder() .region(region) .build(); System.out.println("******* Creating an Amazon DynamoDB table named " + tableName + " with a key named year and a sort key named title."); createTable(ddb, tableName); System.out.println("******* Adding multiple records into the " + tableName + " table using a batch command."); putRecordBatch(ddb); System.out.println("******* Updating multiple records using a batch command."); updateTableItemBatch(ddb); System.out.println("******* Deleting multiple records using a batch command."); deleteItemBatch(ddb); System.out.println("******* Deleting the Amazon DynamoDB table."); deleteDynamoDBTable(ddb, tableName); ddb.close(); } public static void createTable(DynamoDbClient ddb, String tableName) { DynamoDbWaiter dbWaiter = ddb.waiter(); ArrayList<AttributeDefinition> attributeDefinitions = new ArrayList<>(); // Define attributes. attributeDefinitions.add(AttributeDefinition.builder() .attributeName("year") .attributeType("N") .build()); attributeDefinitions.add(AttributeDefinition.builder() .attributeName("title") .attributeType("S") .build()); ArrayList<KeySchemaElement> tableKey = new ArrayList<>(); KeySchemaElement key = KeySchemaElement.builder() .attributeName("year") .keyType(KeyType.HASH) .build(); KeySchemaElement key2 = KeySchemaElement.builder() .attributeName("title") .keyType(KeyType.RANGE) // Sort .build(); // Add KeySchemaElement objects to the list. tableKey.add(key); tableKey.add(key2); CreateTableRequest request = CreateTableRequest.builder() .keySchema(tableKey) .provisionedThroughput(ProvisionedThroughput.builder() .readCapacityUnits(new Long(10)) .writeCapacityUnits(new Long(10)) .build()) .attributeDefinitions(attributeDefinitions) .tableName(tableName) .build(); try { CreateTableResponse response = ddb.createTable(request); DescribeTableRequest tableRequest = DescribeTableRequest.builder() .tableName(tableName) .build(); // Wait until the Amazon DynamoDB table is created. WaiterResponse<DescribeTableResponse> waiterResponse = dbWaiter .waitUntilTableExists(tableRequest); waiterResponse.matched().response().ifPresent(System.out::println); String newTable = response.tableDescription().tableName(); System.out.println("The " + newTable + " was successfully created."); } catch (DynamoDbException e) { System.err.println(e.getMessage()); System.exit(1); } } public static void putRecordBatch(DynamoDbClient ddb) { String sqlStatement = "INSERT INTO MoviesPartiQBatch VALUE {'year':?, 'title' : ?, 'info' : ?}"; try { // Create three movies to add to the Amazon DynamoDB table. // Set data for Movie 1. List<AttributeValue> parameters = new ArrayList<>(); AttributeValue att1 = AttributeValue.builder() .n(String.valueOf("2022")) .build(); AttributeValue att2 = AttributeValue.builder() .s("My Movie 1") .build(); AttributeValue att3 = AttributeValue.builder() .s("No Information") .build(); parameters.add(att1); parameters.add(att2); parameters.add(att3); BatchStatementRequest statementRequestMovie1 = BatchStatementRequest.builder() .statement(sqlStatement) .parameters(parameters) .build(); // Set data for Movie 2. List<AttributeValue> parametersMovie2 = new ArrayList<>(); AttributeValue attMovie2 = AttributeValue.builder() .n(String.valueOf("2022")) .build(); AttributeValue attMovie2A = AttributeValue.builder() .s("My Movie 2") .build(); AttributeValue attMovie2B = AttributeValue.builder() .s("No Information") .build(); parametersMovie2.add(attMovie2); parametersMovie2.add(attMovie2A); parametersMovie2.add(attMovie2B); BatchStatementRequest statementRequestMovie2 = BatchStatementRequest.builder() .statement(sqlStatement) .parameters(parametersMovie2) .build(); // Set data for Movie 3. List<AttributeValue> parametersMovie3 = new ArrayList<>(); AttributeValue attMovie3 = AttributeValue.builder() .n(String.valueOf("2022")) .build(); AttributeValue attMovie3A = AttributeValue.builder() .s("My Movie 3") .build(); AttributeValue attMovie3B = AttributeValue.builder() .s("No Information") .build(); parametersMovie3.add(attMovie3); parametersMovie3.add(attMovie3A); parametersMovie3.add(attMovie3B); BatchStatementRequest statementRequestMovie3 = BatchStatementRequest.builder() .statement(sqlStatement) .parameters(parametersMovie3) .build(); // Add all three movies to the list. List<BatchStatementRequest> myBatchStatementList = new ArrayList<>(); myBatchStatementList.add(statementRequestMovie1); myBatchStatementList.add(statementRequestMovie2); myBatchStatementList.add(statementRequestMovie3); BatchExecuteStatementRequest batchRequest = BatchExecuteStatementRequest.builder() .statements(myBatchStatementList) .build(); BatchExecuteStatementResponse response = ddb.batchExecuteStatement(batchRequest); System.out.println("ExecuteStatement successful: " + response.toString()); System.out.println("Added new movies using a batch command."); } catch (DynamoDbException e) { System.err.println(e.getMessage()); System.exit(1); } } public static void updateTableItemBatch(DynamoDbClient ddb) { String sqlStatement = "UPDATE MoviesPartiQBatch SET info = 'directors\":[\"Merian C. Cooper\",\"Ernest B. Schoedsack' where year=? and title=?"; List<AttributeValue> parametersRec1 = new ArrayList<>(); // Update three records. AttributeValue att1 = AttributeValue.builder() .n(String.valueOf("2022")) .build(); AttributeValue att2 = AttributeValue.builder() .s("My Movie 1") .build(); parametersRec1.add(att1); parametersRec1.add(att2); BatchStatementRequest statementRequestRec1 = BatchStatementRequest.builder() .statement(sqlStatement) .parameters(parametersRec1) .build(); // Update record 2. List<AttributeValue> parametersRec2 = new ArrayList<>(); AttributeValue attRec2 = AttributeValue.builder() .n(String.valueOf("2022")) .build(); AttributeValue attRec2a = AttributeValue.builder() .s("My Movie 2") .build(); parametersRec2.add(attRec2); parametersRec2.add(attRec2a); BatchStatementRequest statementRequestRec2 = BatchStatementRequest.builder() .statement(sqlStatement) .parameters(parametersRec2) .build(); // Update record 3. List<AttributeValue> parametersRec3 = new ArrayList<>(); AttributeValue attRec3 = AttributeValue.builder() .n(String.valueOf("2022")) .build(); AttributeValue attRec3a = AttributeValue.builder() .s("My Movie 3") .build(); parametersRec3.add(attRec3); parametersRec3.add(attRec3a); BatchStatementRequest statementRequestRec3 = BatchStatementRequest.builder() .statement(sqlStatement) .parameters(parametersRec3) .build(); // Add all three movies to the list. List<BatchStatementRequest> myBatchStatementList = new ArrayList<>(); myBatchStatementList.add(statementRequestRec1); myBatchStatementList.add(statementRequestRec2); myBatchStatementList.add(statementRequestRec3); BatchExecuteStatementRequest batchRequest = BatchExecuteStatementRequest.builder() .statements(myBatchStatementList) .build(); try { BatchExecuteStatementResponse response = ddb.batchExecuteStatement(batchRequest); System.out.println("ExecuteStatement successful: " + response.toString()); System.out.println("Updated three movies using a batch command."); } catch (DynamoDbException e) { System.err.println(e.getMessage()); System.exit(1); } System.out.println("Item was updated!"); } public static void deleteItemBatch(DynamoDbClient ddb) { String sqlStatement = "DELETE FROM MoviesPartiQBatch WHERE year = ? and title=?"; List<AttributeValue> parametersRec1 = new ArrayList<>(); // Specify three records to delete. AttributeValue att1 = AttributeValue.builder() .n(String.valueOf("2022")) .build(); AttributeValue att2 = AttributeValue.builder() .s("My Movie 1") .build(); parametersRec1.add(att1); parametersRec1.add(att2); BatchStatementRequest statementRequestRec1 = BatchStatementRequest.builder() .statement(sqlStatement) .parameters(parametersRec1) .build(); // Specify record 2. List<AttributeValue> parametersRec2 = new ArrayList<>(); AttributeValue attRec2 = AttributeValue.builder() .n(String.valueOf("2022")) .build(); AttributeValue attRec2a = AttributeValue.builder() .s("My Movie 2") .build(); parametersRec2.add(attRec2); parametersRec2.add(attRec2a); BatchStatementRequest statementRequestRec2 = BatchStatementRequest.builder() .statement(sqlStatement) .parameters(parametersRec2) .build(); // Specify record 3. List<AttributeValue> parametersRec3 = new ArrayList<>(); AttributeValue attRec3 = AttributeValue.builder() .n(String.valueOf("2022")) .build(); AttributeValue attRec3a = AttributeValue.builder() .s("My Movie 3") .build(); parametersRec3.add(attRec3); parametersRec3.add(attRec3a); BatchStatementRequest statementRequestRec3 = BatchStatementRequest.builder() .statement(sqlStatement) .parameters(parametersRec3) .build(); // Add all three movies to the list. List<BatchStatementRequest> myBatchStatementList = new ArrayList<>(); myBatchStatementList.add(statementRequestRec1); myBatchStatementList.add(statementRequestRec2); myBatchStatementList.add(statementRequestRec3); BatchExecuteStatementRequest batchRequest = BatchExecuteStatementRequest.builder() .statements(myBatchStatementList) .build(); try { ddb.batchExecuteStatement(batchRequest); System.out.println("Deleted three movies using a batch command."); } catch (DynamoDbException e) { System.err.println(e.getMessage()); System.exit(1); } } public static void deleteDynamoDBTable(DynamoDbClient ddb, String tableName) { DeleteTableRequest request = DeleteTableRequest.builder() .tableName(tableName) .build(); try { ddb.deleteTable(request); } catch (DynamoDbException e) { System.err.println(e.getMessage()); System.exit(1); } System.out.println(tableName + " was successfully deleted!"); } private static ExecuteStatementResponse executeStatementRequest(DynamoDbClient ddb, String statement, List<AttributeValue> parameters) { ExecuteStatementRequest request = ExecuteStatementRequest.builder() .statement(statement) .parameters(parameters) .build(); return ddb.executeStatement(request); } }
  • API の詳細については、「 API リファレンスBatchExecuteStatement」の「」を参照してください。 AWS SDK for Java 2.x

次のコードサンプルは、以下の操作方法を示しています。

  • SELECT ステートメントを実行して項目を取得する。

  • INSERT 文を実行して項目を追加する。

  • UPDATE ステートメントを使用して項目を更新する。

  • DELETE ステートメントを実行して項目を削除する。

SDK for Java 2.x
注記

には他にもがあります GitHub。AWS コード例リポジトリ で全く同じ例を見つけて、設定と実行の方法を確認してください。

public class ScenarioPartiQ { public static void main(String[] args) throws IOException { final String usage = """ Usage: <fileName> Where: fileName - The path to the moviedata.json file that you can download from the Amazon DynamoDB Developer Guide. """; if (args.length != 1) { System.out.println(usage); System.exit(1); } String fileName = args[0]; String tableName = "MoviesPartiQ"; Region region = Region.US_EAST_1; DynamoDbClient ddb = DynamoDbClient.builder() .region(region) .build(); System.out.println( "******* Creating an Amazon DynamoDB table named MoviesPartiQ with a key named year and a sort key named title."); createTable(ddb, tableName); System.out.println("******* Loading data into the MoviesPartiQ table."); loadData(ddb, fileName); System.out.println("******* Getting data from the MoviesPartiQ table."); getItem(ddb); System.out.println("******* Putting a record into the MoviesPartiQ table."); putRecord(ddb); System.out.println("******* Updating a record."); updateTableItem(ddb); System.out.println("******* Querying the movies released in 2013."); queryTable(ddb); System.out.println("******* Deleting the Amazon DynamoDB table."); deleteDynamoDBTable(ddb, tableName); ddb.close(); } public static void createTable(DynamoDbClient ddb, String tableName) { DynamoDbWaiter dbWaiter = ddb.waiter(); ArrayList<AttributeDefinition> attributeDefinitions = new ArrayList<>(); // Define attributes. attributeDefinitions.add(AttributeDefinition.builder() .attributeName("year") .attributeType("N") .build()); attributeDefinitions.add(AttributeDefinition.builder() .attributeName("title") .attributeType("S") .build()); ArrayList<KeySchemaElement> tableKey = new ArrayList<>(); KeySchemaElement key = KeySchemaElement.builder() .attributeName("year") .keyType(KeyType.HASH) .build(); KeySchemaElement key2 = KeySchemaElement.builder() .attributeName("title") .keyType(KeyType.RANGE) // Sort .build(); // Add KeySchemaElement objects to the list. tableKey.add(key); tableKey.add(key2); CreateTableRequest request = CreateTableRequest.builder() .keySchema(tableKey) .provisionedThroughput(ProvisionedThroughput.builder() .readCapacityUnits(new Long(10)) .writeCapacityUnits(new Long(10)) .build()) .attributeDefinitions(attributeDefinitions) .tableName(tableName) .build(); try { CreateTableResponse response = ddb.createTable(request); DescribeTableRequest tableRequest = DescribeTableRequest.builder() .tableName(tableName) .build(); // Wait until the Amazon DynamoDB table is created. WaiterResponse<DescribeTableResponse> waiterResponse = dbWaiter.waitUntilTableExists(tableRequest); waiterResponse.matched().response().ifPresent(System.out::println); String newTable = response.tableDescription().tableName(); System.out.println("The " + newTable + " was successfully created."); } catch (DynamoDbException e) { System.err.println(e.getMessage()); System.exit(1); } } // Load data into the table. public static void loadData(DynamoDbClient ddb, String fileName) throws IOException { String sqlStatement = "INSERT INTO MoviesPartiQ VALUE {'year':?, 'title' : ?, 'info' : ?}"; JsonParser parser = new JsonFactory().createParser(new File(fileName)); com.fasterxml.jackson.databind.JsonNode rootNode = new ObjectMapper().readTree(parser); Iterator<JsonNode> iter = rootNode.iterator(); ObjectNode currentNode; int t = 0; List<AttributeValue> parameters = new ArrayList<>(); while (iter.hasNext()) { // Add 200 movies to the table. if (t == 200) break; currentNode = (ObjectNode) iter.next(); int year = currentNode.path("year").asInt(); String title = currentNode.path("title").asText(); String info = currentNode.path("info").toString(); AttributeValue att1 = AttributeValue.builder() .n(String.valueOf(year)) .build(); AttributeValue att2 = AttributeValue.builder() .s(title) .build(); AttributeValue att3 = AttributeValue.builder() .s(info) .build(); parameters.add(att1); parameters.add(att2); parameters.add(att3); // Insert the movie into the Amazon DynamoDB table. executeStatementRequest(ddb, sqlStatement, parameters); System.out.println("Added Movie " + title); parameters.remove(att1); parameters.remove(att2); parameters.remove(att3); t++; } } public static void getItem(DynamoDbClient ddb) { String sqlStatement = "SELECT * FROM MoviesPartiQ where year=? and title=?"; List<AttributeValue> parameters = new ArrayList<>(); AttributeValue att1 = AttributeValue.builder() .n("2012") .build(); AttributeValue att2 = AttributeValue.builder() .s("The Perks of Being a Wallflower") .build(); parameters.add(att1); parameters.add(att2); try { ExecuteStatementResponse response = executeStatementRequest(ddb, sqlStatement, parameters); System.out.println("ExecuteStatement successful: " + response.toString()); } catch (DynamoDbException e) { System.err.println(e.getMessage()); System.exit(1); } } public static void putRecord(DynamoDbClient ddb) { String sqlStatement = "INSERT INTO MoviesPartiQ VALUE {'year':?, 'title' : ?, 'info' : ?}"; try { List<AttributeValue> parameters = new ArrayList<>(); AttributeValue att1 = AttributeValue.builder() .n(String.valueOf("2020")) .build(); AttributeValue att2 = AttributeValue.builder() .s("My Movie") .build(); AttributeValue att3 = AttributeValue.builder() .s("No Information") .build(); parameters.add(att1); parameters.add(att2); parameters.add(att3); executeStatementRequest(ddb, sqlStatement, parameters); System.out.println("Added new movie."); } catch (DynamoDbException e) { System.err.println(e.getMessage()); System.exit(1); } } public static void updateTableItem(DynamoDbClient ddb) { String sqlStatement = "UPDATE MoviesPartiQ SET info = 'directors\":[\"Merian C. Cooper\",\"Ernest B. Schoedsack' where year=? and title=?"; List<AttributeValue> parameters = new ArrayList<>(); AttributeValue att1 = AttributeValue.builder() .n(String.valueOf("2013")) .build(); AttributeValue att2 = AttributeValue.builder() .s("The East") .build(); parameters.add(att1); parameters.add(att2); try { executeStatementRequest(ddb, sqlStatement, parameters); } catch (DynamoDbException e) { System.err.println(e.getMessage()); System.exit(1); } System.out.println("Item was updated!"); } // Query the table where the year is 2013. public static void queryTable(DynamoDbClient ddb) { String sqlStatement = "SELECT * FROM MoviesPartiQ where year = ? ORDER BY year"; try { List<AttributeValue> parameters = new ArrayList<>(); AttributeValue att1 = AttributeValue.builder() .n(String.valueOf("2013")) .build(); parameters.add(att1); // Get items in the table and write out the ID value. ExecuteStatementResponse response = executeStatementRequest(ddb, sqlStatement, parameters); System.out.println("ExecuteStatement successful: " + response.toString()); } catch (DynamoDbException e) { System.err.println(e.getMessage()); System.exit(1); } } public static void deleteDynamoDBTable(DynamoDbClient ddb, String tableName) { DeleteTableRequest request = DeleteTableRequest.builder() .tableName(tableName) .build(); try { ddb.deleteTable(request); } catch (DynamoDbException e) { System.err.println(e.getMessage()); System.exit(1); } System.out.println(tableName + " was successfully deleted!"); } private static ExecuteStatementResponse executeStatementRequest(DynamoDbClient ddb, String statement, List<AttributeValue> parameters) { ExecuteStatementRequest request = ExecuteStatementRequest.builder() .statement(statement) .parameters(parameters) .build(); return ddb.executeStatement(request); } private static void processResults(ExecuteStatementResponse executeStatementResult) { System.out.println("ExecuteStatement successful: " + executeStatementResult.toString()); } }
  • API の詳細については、「 API リファレンスExecuteStatement」の「」を参照してください。 AWS SDK for Java 2.x

サーバーレスサンプル

次のコード例は、DynamoDB ストリームからイベントを受信する Lambda 関数の部分的なバッチレスポンスを実装する方法を示しています。この関数は、レスポンスとしてバッチアイテムの失敗を報告し、対象のメッセージを後で再試行するよう Lambda に伝えます。

SDK for Java 2.x
注記

の詳細については、「」を参照してください GitHub。サーバーレスサンプルリポジトリで完全な例を検索し、設定および実行の方法を確認してください。

Java を使用して Lambda で DynamoDB のバッチアイテム失敗のレポート。

// 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.DynamodbEvent; import com.amazonaws.services.lambda.runtime.events.StreamsEventResponse; import com.amazonaws.services.lambda.runtime.events.models.dynamodb.StreamRecord; import java.io.Serializable; import java.util.ArrayList; import java.util.List; public class ProcessDynamodbRecords implements RequestHandler<DynamodbEvent, Serializable> { @Override public StreamsEventResponse handleRequest(DynamodbEvent input, Context context) { List<StreamsEventResponse.BatchItemFailure> batchItemFailures = new ArrayList<>(); String curRecordSequenceNumber = ""; for (DynamodbEvent.DynamodbStreamRecord dynamodbStreamRecord : input.getRecords()) { try { //Process your record StreamRecord dynamodbRecord = dynamodbStreamRecord.getDynamodb(); curRecordSequenceNumber = dynamodbRecord.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(); } }