Esempi per Amazon Keyspaces con SDK per Java 2.x - Esempi di codice per SDK AWS

Sono disponibili altri esempi per SDK AWS nel repository GitHub della documentazione degli esempi per SDK AWS.

Esempi per Amazon Keyspaces con SDK per Java 2.x

Gli esempi di codice seguenti mostrano come eseguire operazioni e implementare scenari comuni utilizzando AWS SDK for Java 2.x con Amazon Keyspaces.

Nozioni di base: esempi di codice che mostrano come eseguire le operazioni essenziali all’interno di un servizio.

Le azioni sono estratti di codice da programmi più grandi e devono essere eseguite nel contesto. Sebbene le operazioni mostrino come richiamare le singole funzioni del servizio, è possibile visualizzarle contestualizzate negli scenari correlati.

Ogni esempio include un link al codice sorgente completo, in cui vengono fornite le istruzioni su come configurare ed eseguire il codice nel contesto.

Nozioni di base

Gli esempi di codice seguenti mostrano come iniziare a utilizzare Amazon Keyspaces.

SDK per Java 2.x
Nota

Ulteriori informazioni su GitHub. Trova l’esempio completo e scopri di più sulla configurazione e l’esecuzione nel Repository di esempi di codice AWS.

import software.amazon.awssdk.regions.Region; import software.amazon.awssdk.services.keyspaces.KeyspacesClient; import software.amazon.awssdk.services.keyspaces.model.KeyspaceSummary; import software.amazon.awssdk.services.keyspaces.model.KeyspacesException; import software.amazon.awssdk.services.keyspaces.model.ListKeyspacesRequest; import software.amazon.awssdk.services.keyspaces.model.ListKeyspacesResponse; 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 HelloKeyspaces { public static void main(String[] args) { Region region = Region.US_EAST_1; KeyspacesClient keyClient = KeyspacesClient.builder() .region(region) .build(); listKeyspaces(keyClient); } public static void listKeyspaces(KeyspacesClient keyClient) { try { ListKeyspacesRequest keyspacesRequest = ListKeyspacesRequest.builder() .maxResults(10) .build(); ListKeyspacesResponse response = keyClient.listKeyspaces(keyspacesRequest); List<KeyspaceSummary> keyspaces = response.keyspaces(); for (KeyspaceSummary keyspace : keyspaces) { System.out.println("The name of the keyspace is " + keyspace.keyspaceName()); } } catch (KeyspacesException e) { System.err.println(e.awsErrorDetails().errorMessage()); System.exit(1); } } }
  • Per informazioni dettagliate sull’API, consulta ListKeyspaces nella documentazione di riferimento dell’API AWS SDK for Java 2.x.

Nozioni di base

L’esempio di codice seguente mostra come:

  • Creare un keyspace e una tabella. Lo schema della tabella contiene i dati dei film e il recupero point-in-time (PITR) abilitato.

  • Stabilire la connessione al keyspace utilizzando una connessione TLS sicura con l’autenticazione SigV4.

  • Esegui una query sulla tabella. Aggiungere, recuperare e aggiornare i dati dei film.

  • Aggiornare la tabella. Aggiungere una colonna per monitorare i film visionati.

  • Ripristinare lo stato precedente della tabella ed eseguire la pulizia delle risorse.

SDK per Java 2.x
Nota

Ulteriori informazioni su GitHub. Trova l’esempio completo e scopri di più sulla configurazione e l’esecuzione nel Repository di esempi di codice AWS.

/** * 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 * * Before running this Java code example, you must create a * Java keystore (JKS) file and place it in your project's resources folder. * * This file is a secure file format used to hold certificate information for * Java applications. This is required to make a connection to Amazon Keyspaces. * For more information, see the following documentation topic: * * https://docs.aws.amazon.com/keyspaces/latest/devguide/using_java_driver.html * * This Java example performs the following tasks: * * 1. Create a keyspace. * 2. Check for keyspace existence. * 3. List keyspaces using a paginator. * 4. Create a table with a simple movie data schema and enable point-in-time * recovery. * 5. Check for the table to be in an Active state. * 6. List all tables in the keyspace. * 7. Use a Cassandra driver to insert some records into the Movie table. * 8. Get all records from the Movie table. * 9. Get a specific Movie. * 10. Get a UTC timestamp for the current time. * 11. Update the table schema to add a ‘watched’ Boolean column. * 12. Update an item as watched. * 13. Query for items with watched = True. * 14. Restore the table back to the previous state using the timestamp. * 15. Check for completion of the restore action. * 16. Delete the table. * 17. Confirm that both tables are deleted. * 18. Delete the keyspace. */ public class ScenarioKeyspaces { public static final String DASHES = new String(new char[80]).replace("\0", "-"); /* * Usage: * fileName - The name of the JSON file that contains movie data. (Get this file * from the GitHub repo at resources/sample_file.) * keyspaceName - The name of the keyspace to create. */ public static void main(String[] args) throws InterruptedException, IOException { String fileName = "<Replace with the JSON file that contains movie data>"; String keyspaceName = "<Replace with the name of the keyspace to create>"; String titleUpdate = "The Family"; int yearUpdate = 2013; String tableName = "Movie"; String tableNameRestore = "MovieRestore"; Region region = Region.US_EAST_1; KeyspacesClient keyClient = KeyspacesClient.builder() .region(region) .build(); DriverConfigLoader loader = DriverConfigLoader.fromClasspath("application.conf"); CqlSession session = CqlSession.builder() .withConfigLoader(loader) .build(); System.out.println(DASHES); System.out.println("Welcome to the Amazon Keyspaces example scenario."); System.out.println(DASHES); System.out.println(DASHES); System.out.println("1. Create a keyspace."); createKeySpace(keyClient, keyspaceName); System.out.println(DASHES); System.out.println(DASHES); Thread.sleep(5000); System.out.println("2. Check for keyspace existence."); checkKeyspaceExistence(keyClient, keyspaceName); System.out.println(DASHES); System.out.println(DASHES); System.out.println("3. List keyspaces using a paginator."); listKeyspacesPaginator(keyClient); System.out.println(DASHES); System.out.println(DASHES); System.out.println("4. Create a table with a simple movie data schema and enable point-in-time recovery."); createTable(keyClient, keyspaceName, tableName); System.out.println(DASHES); System.out.println(DASHES); System.out.println("5. Check for the table to be in an Active state."); Thread.sleep(6000); checkTable(keyClient, keyspaceName, tableName); System.out.println(DASHES); System.out.println(DASHES); System.out.println("6. List all tables in the keyspace."); listTables(keyClient, keyspaceName); System.out.println(DASHES); System.out.println(DASHES); System.out.println("7. Use a Cassandra driver to insert some records into the Movie table."); Thread.sleep(6000); loadData(session, fileName, keyspaceName); System.out.println(DASHES); System.out.println(DASHES); System.out.println("8. Get all records from the Movie table."); getMovieData(session, keyspaceName); System.out.println(DASHES); System.out.println(DASHES); System.out.println("9. Get a specific Movie."); getSpecificMovie(session, keyspaceName); System.out.println(DASHES); System.out.println(DASHES); System.out.println("10. Get a UTC timestamp for the current time."); ZonedDateTime utc = ZonedDateTime.now(ZoneOffset.UTC); System.out.println("DATETIME = " + Date.from(utc.toInstant())); System.out.println(DASHES); System.out.println(DASHES); System.out.println("11. Update the table schema to add a watched Boolean column."); updateTable(keyClient, keyspaceName, tableName); System.out.println(DASHES); System.out.println(DASHES); System.out.println("12. Update an item as watched."); Thread.sleep(10000); // Wait 10 secs for the update. updateRecord(session, keyspaceName, titleUpdate, yearUpdate); System.out.println(DASHES); System.out.println(DASHES); System.out.println("13. Query for items with watched = True."); getWatchedData(session, keyspaceName); System.out.println(DASHES); System.out.println(DASHES); System.out.println("14. Restore the table back to the previous state using the timestamp."); System.out.println("Note that the restore operation can take up to 20 minutes."); restoreTable(keyClient, keyspaceName, utc); System.out.println(DASHES); System.out.println(DASHES); System.out.println("15. Check for completion of the restore action."); Thread.sleep(5000); checkRestoredTable(keyClient, keyspaceName, "MovieRestore"); System.out.println(DASHES); System.out.println(DASHES); System.out.println("16. Delete both tables."); deleteTable(keyClient, keyspaceName, tableName); deleteTable(keyClient, keyspaceName, tableNameRestore); System.out.println(DASHES); System.out.println(DASHES); System.out.println("17. Confirm that both tables are deleted."); checkTableDelete(keyClient, keyspaceName, tableName); checkTableDelete(keyClient, keyspaceName, tableNameRestore); System.out.println(DASHES); System.out.println(DASHES); System.out.println("18. Delete the keyspace."); deleteKeyspace(keyClient, keyspaceName); System.out.println(DASHES); System.out.println(DASHES); System.out.println("The scenario has completed successfully."); System.out.println(DASHES); } public static void deleteKeyspace(KeyspacesClient keyClient, String keyspaceName) { try { DeleteKeyspaceRequest deleteKeyspaceRequest = DeleteKeyspaceRequest.builder() .keyspaceName(keyspaceName) .build(); keyClient.deleteKeyspace(deleteKeyspaceRequest); } catch (KeyspacesException e) { System.err.println(e.awsErrorDetails().errorMessage()); System.exit(1); } } public static void checkTableDelete(KeyspacesClient keyClient, String keyspaceName, String tableName) throws InterruptedException { try { String status; GetTableResponse response; GetTableRequest tableRequest = GetTableRequest.builder() .keyspaceName(keyspaceName) .tableName(tableName) .build(); // Keep looping until table cannot be found and a ResourceNotFoundException is // thrown. while (true) { response = keyClient.getTable(tableRequest); status = response.statusAsString(); System.out.println(". The table status is " + status); Thread.sleep(500); } } catch (ResourceNotFoundException e) { System.err.println(e.awsErrorDetails().errorMessage()); } System.out.println("The table is deleted"); } public static void deleteTable(KeyspacesClient keyClient, String keyspaceName, String tableName) { try { DeleteTableRequest tableRequest = DeleteTableRequest.builder() .keyspaceName(keyspaceName) .tableName(tableName) .build(); keyClient.deleteTable(tableRequest); } catch (KeyspacesException e) { System.err.println(e.awsErrorDetails().errorMessage()); System.exit(1); } } public static void checkRestoredTable(KeyspacesClient keyClient, String keyspaceName, String tableName) throws InterruptedException { try { boolean tableStatus = false; String status; GetTableResponse response = null; GetTableRequest tableRequest = GetTableRequest.builder() .keyspaceName(keyspaceName) .tableName(tableName) .build(); while (!tableStatus) { response = keyClient.getTable(tableRequest); status = response.statusAsString(); System.out.println("The table status is " + status); if (status.compareTo("ACTIVE") == 0) { tableStatus = true; } Thread.sleep(500); } List<ColumnDefinition> cols = response.schemaDefinition().allColumns(); for (ColumnDefinition def : cols) { System.out.println("The column name is " + def.name()); System.out.println("The column type is " + def.type()); } } catch (KeyspacesException e) { System.err.println(e.awsErrorDetails().errorMessage()); System.exit(1); } } public static void restoreTable(KeyspacesClient keyClient, String keyspaceName, ZonedDateTime utc) { try { Instant myTime = utc.toInstant(); RestoreTableRequest restoreTableRequest = RestoreTableRequest.builder() .restoreTimestamp(myTime) .sourceTableName("Movie") .targetKeyspaceName(keyspaceName) .targetTableName("MovieRestore") .sourceKeyspaceName(keyspaceName) .build(); RestoreTableResponse response = keyClient.restoreTable(restoreTableRequest); System.out.println("The ARN of the restored table is " + response.restoredTableARN()); } catch (KeyspacesException e) { System.err.println(e.awsErrorDetails().errorMessage()); System.exit(1); } } public static void getWatchedData(CqlSession session, String keyspaceName) { ResultSet resultSet = session .execute("SELECT * FROM \"" + keyspaceName + "\".\"Movie\" WHERE watched = true ALLOW FILTERING;"); resultSet.forEach(item -> { System.out.println("The Movie title is " + item.getString("title")); System.out.println("The Movie year is " + item.getInt("year")); System.out.println("The plot is " + item.getString("plot")); }); } public static void updateRecord(CqlSession session, String keySpace, String titleUpdate, int yearUpdate) { String sqlStatement = "UPDATE \"" + keySpace + "\".\"Movie\" SET watched=true WHERE title = :k0 AND year = :k1;"; BatchStatementBuilder builder = BatchStatement.builder(DefaultBatchType.UNLOGGED); builder.setConsistencyLevel(ConsistencyLevel.LOCAL_QUORUM); PreparedStatement preparedStatement = session.prepare(sqlStatement); builder.addStatement(preparedStatement.boundStatementBuilder() .setString("k0", titleUpdate) .setInt("k1", yearUpdate) .build()); BatchStatement batchStatement = builder.build(); session.execute(batchStatement); } public static void updateTable(KeyspacesClient keyClient, String keySpace, String tableName) { try { ColumnDefinition def = ColumnDefinition.builder() .name("watched") .type("boolean") .build(); UpdateTableRequest tableRequest = UpdateTableRequest.builder() .keyspaceName(keySpace) .tableName(tableName) .addColumns(def) .build(); keyClient.updateTable(tableRequest); } catch (KeyspacesException e) { System.err.println(e.awsErrorDetails().errorMessage()); System.exit(1); } } public static void getSpecificMovie(CqlSession session, String keyspaceName) { ResultSet resultSet = session.execute( "SELECT * FROM \"" + keyspaceName + "\".\"Movie\" WHERE title = 'The Family' ALLOW FILTERING ;"); resultSet.forEach(item -> { System.out.println("The Movie title is " + item.getString("title")); System.out.println("The Movie year is " + item.getInt("year")); System.out.println("The plot is " + item.getString("plot")); }); } // Get records from the Movie table. public static void getMovieData(CqlSession session, String keyspaceName) { ResultSet resultSet = session.execute("SELECT * FROM \"" + keyspaceName + "\".\"Movie\";"); resultSet.forEach(item -> { System.out.println("The Movie title is " + item.getString("title")); System.out.println("The Movie year is " + item.getInt("year")); System.out.println("The plot is " + item.getString("plot")); }); } // Load data into the table. public static void loadData(CqlSession session, String fileName, String keySpace) throws IOException { String sqlStatement = "INSERT INTO \"" + keySpace + "\".\"Movie\" (title, year, plot) values (:k0, :k1, :k2)"; 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()) { // Add 20 movies to the table. if (t == 20) break; currentNode = (ObjectNode) iter.next(); int year = currentNode.path("year").asInt(); String title = currentNode.path("title").asText(); String plot = currentNode.path("info").path("plot").toString(); // Insert the data into the Amazon Keyspaces table. BatchStatementBuilder builder = BatchStatement.builder(DefaultBatchType.UNLOGGED); builder.setConsistencyLevel(ConsistencyLevel.LOCAL_QUORUM); PreparedStatement preparedStatement = session.prepare(sqlStatement); builder.addStatement(preparedStatement.boundStatementBuilder() .setString("k0", title) .setInt("k1", year) .setString("k2", plot) .build()); BatchStatement batchStatement = builder.build(); session.execute(batchStatement); t++; } System.out.println("You have added " + t + " records successfully!"); } public static void listTables(KeyspacesClient keyClient, String keyspaceName) { try { ListTablesRequest tablesRequest = ListTablesRequest.builder() .keyspaceName(keyspaceName) .build(); ListTablesIterable listRes = keyClient.listTablesPaginator(tablesRequest); listRes.stream() .flatMap(r -> r.tables().stream()) .forEach(content -> System.out.println(" ARN: " + content.resourceArn() + " Table name: " + content.tableName())); } catch (KeyspacesException e) { System.err.println(e.awsErrorDetails().errorMessage()); System.exit(1); } } public static void checkTable(KeyspacesClient keyClient, String keyspaceName, String tableName) throws InterruptedException { try { boolean tableStatus = false; String status; GetTableResponse response = null; GetTableRequest tableRequest = GetTableRequest.builder() .keyspaceName(keyspaceName) .tableName(tableName) .build(); while (!tableStatus) { response = keyClient.getTable(tableRequest); status = response.statusAsString(); System.out.println(". The table status is " + status); if (status.compareTo("ACTIVE") == 0) { tableStatus = true; } Thread.sleep(500); } List<ColumnDefinition> cols = response.schemaDefinition().allColumns(); for (ColumnDefinition def : cols) { System.out.println("The column name is " + def.name()); System.out.println("The column type is " + def.type()); } } catch (KeyspacesException e) { System.err.println(e.awsErrorDetails().errorMessage()); System.exit(1); } } public static void createTable(KeyspacesClient keyClient, String keySpace, String tableName) { try { // Set the columns. ColumnDefinition defTitle = ColumnDefinition.builder() .name("title") .type("text") .build(); ColumnDefinition defYear = ColumnDefinition.builder() .name("year") .type("int") .build(); ColumnDefinition defReleaseDate = ColumnDefinition.builder() .name("release_date") .type("timestamp") .build(); ColumnDefinition defPlot = ColumnDefinition.builder() .name("plot") .type("text") .build(); List<ColumnDefinition> colList = new ArrayList<>(); colList.add(defTitle); colList.add(defYear); colList.add(defReleaseDate); colList.add(defPlot); // Set the keys. PartitionKey yearKey = PartitionKey.builder() .name("year") .build(); PartitionKey titleKey = PartitionKey.builder() .name("title") .build(); List<PartitionKey> keyList = new ArrayList<>(); keyList.add(yearKey); keyList.add(titleKey); SchemaDefinition schemaDefinition = SchemaDefinition.builder() .partitionKeys(keyList) .allColumns(colList) .build(); PointInTimeRecovery timeRecovery = PointInTimeRecovery.builder() .status(PointInTimeRecoveryStatus.ENABLED) .build(); CreateTableRequest tableRequest = CreateTableRequest.builder() .keyspaceName(keySpace) .tableName(tableName) .schemaDefinition(schemaDefinition) .pointInTimeRecovery(timeRecovery) .build(); CreateTableResponse response = keyClient.createTable(tableRequest); System.out.println("The table ARN is " + response.resourceArn()); } catch (KeyspacesException e) { System.err.println(e.awsErrorDetails().errorMessage()); System.exit(1); } } public static void listKeyspacesPaginator(KeyspacesClient keyClient) { try { ListKeyspacesRequest keyspacesRequest = ListKeyspacesRequest.builder() .maxResults(10) .build(); ListKeyspacesIterable listRes = keyClient.listKeyspacesPaginator(keyspacesRequest); listRes.stream() .flatMap(r -> r.keyspaces().stream()) .forEach(content -> System.out.println(" Name: " + content.keyspaceName())); } catch (KeyspacesException e) { System.err.println(e.awsErrorDetails().errorMessage()); System.exit(1); } } public static void checkKeyspaceExistence(KeyspacesClient keyClient, String keyspaceName) { try { GetKeyspaceRequest keyspaceRequest = GetKeyspaceRequest.builder() .keyspaceName(keyspaceName) .build(); GetKeyspaceResponse response = keyClient.getKeyspace(keyspaceRequest); String name = response.keyspaceName(); System.out.println("The " + name + " KeySpace is ready"); } catch (KeyspacesException e) { System.err.println(e.awsErrorDetails().errorMessage()); System.exit(1); } } public static void createKeySpace(KeyspacesClient keyClient, String keyspaceName) { try { CreateKeyspaceRequest keyspaceRequest = CreateKeyspaceRequest.builder() .keyspaceName(keyspaceName) .build(); CreateKeyspaceResponse response = keyClient.createKeyspace(keyspaceRequest); System.out.println("The ARN of the KeySpace is " + response.resourceArn()); } catch (KeyspacesException e) { System.err.println(e.awsErrorDetails().errorMessage()); System.exit(1); } } }

Azioni

L’esempio di codice seguente mostra come utilizzare CreateKeyspace.

SDK per Java 2.x
Nota

Ulteriori informazioni su GitHub. Trova l’esempio completo e scopri di più sulla configurazione e l’esecuzione nel Repository di esempi di codice AWS.

public static void createKeySpace(KeyspacesClient keyClient, String keyspaceName) { try { CreateKeyspaceRequest keyspaceRequest = CreateKeyspaceRequest.builder() .keyspaceName(keyspaceName) .build(); CreateKeyspaceResponse response = keyClient.createKeyspace(keyspaceRequest); System.out.println("The ARN of the KeySpace is " + response.resourceArn()); } catch (KeyspacesException e) { System.err.println(e.awsErrorDetails().errorMessage()); System.exit(1); } }
  • Per informazioni dettagliate sull’API, consulta CreateKeyspace nella documentazione di riferimento dell’API AWS SDK for Java 2.x.

L’esempio di codice seguente mostra come utilizzare CreateTable.

SDK per Java 2.x
Nota

Ulteriori informazioni su GitHub. Trova l’esempio completo e scopri di più sulla configurazione e l’esecuzione nel Repository di esempi di codice AWS.

public static void createTable(KeyspacesClient keyClient, String keySpace, String tableName) { try { // Set the columns. ColumnDefinition defTitle = ColumnDefinition.builder() .name("title") .type("text") .build(); ColumnDefinition defYear = ColumnDefinition.builder() .name("year") .type("int") .build(); ColumnDefinition defReleaseDate = ColumnDefinition.builder() .name("release_date") .type("timestamp") .build(); ColumnDefinition defPlot = ColumnDefinition.builder() .name("plot") .type("text") .build(); List<ColumnDefinition> colList = new ArrayList<>(); colList.add(defTitle); colList.add(defYear); colList.add(defReleaseDate); colList.add(defPlot); // Set the keys. PartitionKey yearKey = PartitionKey.builder() .name("year") .build(); PartitionKey titleKey = PartitionKey.builder() .name("title") .build(); List<PartitionKey> keyList = new ArrayList<>(); keyList.add(yearKey); keyList.add(titleKey); SchemaDefinition schemaDefinition = SchemaDefinition.builder() .partitionKeys(keyList) .allColumns(colList) .build(); PointInTimeRecovery timeRecovery = PointInTimeRecovery.builder() .status(PointInTimeRecoveryStatus.ENABLED) .build(); CreateTableRequest tableRequest = CreateTableRequest.builder() .keyspaceName(keySpace) .tableName(tableName) .schemaDefinition(schemaDefinition) .pointInTimeRecovery(timeRecovery) .build(); CreateTableResponse response = keyClient.createTable(tableRequest); System.out.println("The table ARN is " + response.resourceArn()); } catch (KeyspacesException e) { System.err.println(e.awsErrorDetails().errorMessage()); System.exit(1); } }
  • Per informazioni dettagliate sull’API, consulta CreateTable nella documentazione di riferimento dell’API AWS SDK for Java 2.x.

L’esempio di codice seguente mostra come utilizzare DeleteKeyspace.

SDK per Java 2.x
Nota

Ulteriori informazioni su GitHub. Trova l’esempio completo e scopri di più sulla configurazione e l’esecuzione nel Repository di esempi di codice AWS.

public static void deleteKeyspace(KeyspacesClient keyClient, String keyspaceName) { try { DeleteKeyspaceRequest deleteKeyspaceRequest = DeleteKeyspaceRequest.builder() .keyspaceName(keyspaceName) .build(); keyClient.deleteKeyspace(deleteKeyspaceRequest); } catch (KeyspacesException e) { System.err.println(e.awsErrorDetails().errorMessage()); System.exit(1); } }
  • Per informazioni dettagliate sull’API, consulta DeleteKeyspace nella documentazione di riferimento dell’API AWS SDK for Java 2.x.

L’esempio di codice seguente mostra come utilizzare DeleteTable.

SDK per Java 2.x
Nota

Ulteriori informazioni su GitHub. Trova l’esempio completo e scopri di più sulla configurazione e l’esecuzione nel Repository di esempi di codice AWS.

public static void deleteTable(KeyspacesClient keyClient, String keyspaceName, String tableName) { try { DeleteTableRequest tableRequest = DeleteTableRequest.builder() .keyspaceName(keyspaceName) .tableName(tableName) .build(); keyClient.deleteTable(tableRequest); } catch (KeyspacesException e) { System.err.println(e.awsErrorDetails().errorMessage()); System.exit(1); } }
  • Per informazioni dettagliate sull’API, consulta DeleteTable nella documentazione di riferimento dell’API AWS SDK for Java 2.x.

L’esempio di codice seguente mostra come utilizzare GetKeyspace.

SDK per Java 2.x
Nota

Ulteriori informazioni su GitHub. Trova l’esempio completo e scopri di più sulla configurazione e l’esecuzione nel Repository di esempi di codice AWS.

public static void checkKeyspaceExistence(KeyspacesClient keyClient, String keyspaceName) { try { GetKeyspaceRequest keyspaceRequest = GetKeyspaceRequest.builder() .keyspaceName(keyspaceName) .build(); GetKeyspaceResponse response = keyClient.getKeyspace(keyspaceRequest); String name = response.keyspaceName(); System.out.println("The " + name + " KeySpace is ready"); } catch (KeyspacesException e) { System.err.println(e.awsErrorDetails().errorMessage()); System.exit(1); } }
  • Per informazioni dettagliate sull’API, consulta GetKeyspace nella documentazione di riferimento dell’API AWS SDK for Java 2.x.

L’esempio di codice seguente mostra come utilizzare GetTable.

SDK per Java 2.x
Nota

Ulteriori informazioni su GitHub. Trova l’esempio completo e scopri di più sulla configurazione e l’esecuzione nel Repository di esempi di codice AWS.

public static void checkTable(KeyspacesClient keyClient, String keyspaceName, String tableName) throws InterruptedException { try { boolean tableStatus = false; String status; GetTableResponse response = null; GetTableRequest tableRequest = GetTableRequest.builder() .keyspaceName(keyspaceName) .tableName(tableName) .build(); while (!tableStatus) { response = keyClient.getTable(tableRequest); status = response.statusAsString(); System.out.println(". The table status is " + status); if (status.compareTo("ACTIVE") == 0) { tableStatus = true; } Thread.sleep(500); } List<ColumnDefinition> cols = response.schemaDefinition().allColumns(); for (ColumnDefinition def : cols) { System.out.println("The column name is " + def.name()); System.out.println("The column type is " + def.type()); } } catch (KeyspacesException e) { System.err.println(e.awsErrorDetails().errorMessage()); System.exit(1); } }
  • Per informazioni dettagliate sull’API, consulta GetTable nella documentazione di riferimento dell’API AWS SDK for Java 2.x.

L’esempio di codice seguente mostra come utilizzare ListKeyspaces.

SDK per Java 2.x
Nota

Ulteriori informazioni su GitHub. Trova l’esempio completo e scopri di più sulla configurazione e l’esecuzione nel Repository di esempi di codice AWS.

public static void listKeyspacesPaginator(KeyspacesClient keyClient) { try { ListKeyspacesRequest keyspacesRequest = ListKeyspacesRequest.builder() .maxResults(10) .build(); ListKeyspacesIterable listRes = keyClient.listKeyspacesPaginator(keyspacesRequest); listRes.stream() .flatMap(r -> r.keyspaces().stream()) .forEach(content -> System.out.println(" Name: " + content.keyspaceName())); } catch (KeyspacesException e) { System.err.println(e.awsErrorDetails().errorMessage()); System.exit(1); } }
  • Per informazioni dettagliate sull’API, consulta ListKeyspaces nella documentazione di riferimento dell’API AWS SDK for Java 2.x.

L’esempio di codice seguente mostra come utilizzare ListTables.

SDK per Java 2.x
Nota

Ulteriori informazioni su GitHub. Trova l’esempio completo e scopri di più sulla configurazione e l’esecuzione nel Repository di esempi di codice AWS.

public static void listTables(KeyspacesClient keyClient, String keyspaceName) { try { ListTablesRequest tablesRequest = ListTablesRequest.builder() .keyspaceName(keyspaceName) .build(); ListTablesIterable listRes = keyClient.listTablesPaginator(tablesRequest); listRes.stream() .flatMap(r -> r.tables().stream()) .forEach(content -> System.out.println(" ARN: " + content.resourceArn() + " Table name: " + content.tableName())); } catch (KeyspacesException e) { System.err.println(e.awsErrorDetails().errorMessage()); System.exit(1); } }
  • Per informazioni dettagliate sull’API, consulta ListTables nella documentazione di riferimento dell’API AWS SDK for Java 2.x.

L’esempio di codice seguente mostra come utilizzare RestoreTable.

SDK per Java 2.x
Nota

Ulteriori informazioni su GitHub. Trova l’esempio completo e scopri di più sulla configurazione e l’esecuzione nel Repository di esempi di codice AWS.

public static void restoreTable(KeyspacesClient keyClient, String keyspaceName, ZonedDateTime utc) { try { Instant myTime = utc.toInstant(); RestoreTableRequest restoreTableRequest = RestoreTableRequest.builder() .restoreTimestamp(myTime) .sourceTableName("Movie") .targetKeyspaceName(keyspaceName) .targetTableName("MovieRestore") .sourceKeyspaceName(keyspaceName) .build(); RestoreTableResponse response = keyClient.restoreTable(restoreTableRequest); System.out.println("The ARN of the restored table is " + response.restoredTableARN()); } catch (KeyspacesException e) { System.err.println(e.awsErrorDetails().errorMessage()); System.exit(1); } }
  • Per informazioni dettagliate sull’API, consulta RestoreTable nella documentazione di riferimento dell’API AWS SDK for Java 2.x.

L’esempio di codice seguente mostra come utilizzare UpdateTable.

SDK per Java 2.x
Nota

Ulteriori informazioni su GitHub. Trova l’esempio completo e scopri di più sulla configurazione e l’esecuzione nel Repository di esempi di codice AWS.

public static void updateTable(KeyspacesClient keyClient, String keySpace, String tableName) { try { ColumnDefinition def = ColumnDefinition.builder() .name("watched") .type("boolean") .build(); UpdateTableRequest tableRequest = UpdateTableRequest.builder() .keyspaceName(keySpace) .tableName(tableName) .addColumns(def) .build(); keyClient.updateTable(tableRequest); } catch (KeyspacesException e) { System.err.println(e.awsErrorDetails().errorMessage()); System.exit(1); } }
  • Per informazioni dettagliate sull’API, consulta UpdateTable nella documentazione di riferimento dell’API AWS SDK for Java 2.x.