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SDK适用于 Java 2.x 的 Amazon Keyspaces 示例
以下代码示例向您展示了如何使用 Amazon SDK for Java 2.x 与 Amazon Keyspaces 配合使用来执行操作和实现常见场景。
基础知识是向您展示如何在服务中执行基本操作的代码示例。
操作是大型程序的代码摘录,必须在上下文中运行。您可以通过操作了解如何调用单个服务函数,还可以通过函数相关场景的上下文查看操作。
每个示例都包含一个指向完整源代码的链接,您可以在其中找到有关如何在上下文中设置和运行代码的说明。
开始使用
以下代码示例展示了如何开始使用 Amazon Keyspaces。
- SDK适用于 Java 2.x
-
注意
还有更多相关信息 GitHub。查找完整示例,学习如何在 Amazon 代码示例存储库
中进行设置和运行。 import software.amazon.awssdk.regions.Region; import software.amazon.awssdk.services.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); } } }
-
有关API详细信息,请参阅 “Amazon SDK for Java 2.x API参考 ListKeyspaces” 中的。
-
基础知识
以下代码示例展示了如何:
创建密钥空间和表。表架构保存电影数据并启用了 point-in-time恢复。
使用带有 Sigv4 身份验证的安全TLS连接连接到密钥空间。
查询表。添加、检索和更新电影数据。
更新表。添加一列来跟踪观看的电影。
将表还原到以前的状态并清理资源。
- SDK适用于 Java 2.x
-
注意
还有更多相关信息 GitHub。查找完整示例,学习如何在 Amazon 代码示例存储库
中进行设置和运行。 /** * 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); } } }
-
有关API详细信息,请参阅 “参Amazon SDK for Java 2.x API考” 中的以下主题。
-
操作
以下代码示例演示如何使用 CreateKeyspace
。
- SDK适用于 Java 2.x
-
注意
还有更多相关信息 GitHub。查找完整示例,学习如何在 Amazon 代码示例存储库
中进行设置和运行。 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); } }
-
有关API详细信息,请参阅 “Amazon SDK for Java 2.x API参考 CreateKeyspace” 中的。
-
以下代码示例演示如何使用 CreateTable
。
- SDK适用于 Java 2.x
-
注意
还有更多相关信息 GitHub。查找完整示例,学习如何在 Amazon 代码示例存储库
中进行设置和运行。 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); } }
-
有关API详细信息,请参阅 “Amazon SDK for Java 2.x API参考 CreateTable” 中的。
-
以下代码示例演示如何使用 DeleteKeyspace
。
- SDK适用于 Java 2.x
-
注意
还有更多相关信息 GitHub。查找完整示例,学习如何在 Amazon 代码示例存储库
中进行设置和运行。 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); } }
-
有关API详细信息,请参阅 “Amazon SDK for Java 2.x API参考 DeleteKeyspace” 中的。
-
以下代码示例演示如何使用 DeleteTable
。
- SDK适用于 Java 2.x
-
注意
还有更多相关信息 GitHub。查找完整示例,学习如何在 Amazon 代码示例存储库
中进行设置和运行。 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); } }
-
有关API详细信息,请参阅 “Amazon SDK for Java 2.x API参考 DeleteTable” 中的。
-
以下代码示例演示如何使用 GetKeyspace
。
- SDK适用于 Java 2.x
-
注意
还有更多相关信息 GitHub。查找完整示例,学习如何在 Amazon 代码示例存储库
中进行设置和运行。 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); } }
-
有关API详细信息,请参阅 “Amazon SDK for Java 2.x API参考 GetKeyspace” 中的。
-
以下代码示例演示如何使用 GetTable
。
- SDK适用于 Java 2.x
-
注意
还有更多相关信息 GitHub。查找完整示例,学习如何在 Amazon 代码示例存储库
中进行设置和运行。 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); } }
-
有关API详细信息,请参阅 “Amazon SDK for Java 2.x API参考 GetTable” 中的。
-
以下代码示例演示如何使用 ListKeyspaces
。
- SDK适用于 Java 2.x
-
注意
还有更多相关信息 GitHub。查找完整示例,学习如何在 Amazon 代码示例存储库
中进行设置和运行。 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); } }
-
有关API详细信息,请参阅 “Amazon SDK for Java 2.x API参考 ListKeyspaces” 中的。
-
以下代码示例演示如何使用 ListTables
。
- SDK适用于 Java 2.x
-
注意
还有更多相关信息 GitHub。查找完整示例,学习如何在 Amazon 代码示例存储库
中进行设置和运行。 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); } }
-
有关API详细信息,请参阅 “Amazon SDK for Java 2.x API参考 ListTables” 中的。
-
以下代码示例演示如何使用 RestoreTable
。
- SDK适用于 Java 2.x
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注意
还有更多相关信息 GitHub。查找完整示例,学习如何在 Amazon 代码示例存储库
中进行设置和运行。 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); } }
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有关API详细信息,请参阅 “Amazon SDK for Java 2.x API参考 RestoreTable” 中的。
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以下代码示例演示如何使用 UpdateTable
。
- SDK适用于 Java 2.x
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注意
还有更多相关信息 GitHub。查找完整示例,学习如何在 Amazon 代码示例存储库
中进行设置和运行。 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); } }
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有关API详细信息,请参阅 “Amazon SDK for Java 2.x API参考 UpdateTable” 中的。
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