使用 SDK for Java 2.x 的 Amazon Keyspaces 示例

以下代码示例演示如何将 AWS SDK for Java 2.x 与 Amazon Keyspaces 结合使用来执行操作和实现常见场景。

操作是大型程序的代码摘录，必须在上下文中运行。您可以通过操作了解如何调用单个服务函数，还可以通过函数相关场景和跨服务示例的上下文查看操作。

场景是指显示如何通过在同一服务中调用多个函数来完成特定任务的代码示例。

每个示例都包含一个指向的链接 GitHub，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

开始使用 Amazon Keyspaces

以下代码示例演示如何开始使用 Amazon Keyspaces。

适用于 Java 2.x 的 SDK

注意

还有更多相关信息 GitHub。在 AWS 代码示例存储库中查找完整示例，了解如何进行设置和运行。

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 的详细信息，请参阅 AWS SDK for Java 2.xAPI 参考ListKeyspaces中的。

操作

创建键空间

以下代码示例演示如何创建 Amazon Keyspaces 键空间。

适用于 Java 2.x 的 SDK

注意

还有更多相关信息 GitHub。在 AWS 代码示例存储库中查找完整示例，了解如何进行设置和运行。

    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 的详细信息，请参阅 AWS SDK for Java 2.xAPI 参考CreateKeyspace中的。

创建表

以下代码示例演示如何创建 Amazon Keyspaces 表。

适用于 Java 2.x 的 SDK

注意

还有更多相关信息 GitHub。在 AWS 代码示例存储库中查找完整示例，了解如何进行设置和运行。

    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 的详细信息，请参阅 AWS SDK for Java 2.xAPI 参考CreateTable中的。

删除键空间

以下代码示例演示如何删除 Amazon Keyspaces 键空间。

适用于 Java 2.x 的 SDK

注意

还有更多相关信息 GitHub。在 AWS 代码示例存储库中查找完整示例，了解如何进行设置和运行。

    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 的详细信息，请参阅 AWS SDK for Java 2.xAPI 参考DeleteKeyspace中的。

删除表

以下代码示例演示如何删除 Amazon Keyspaces 表。

适用于 Java 2.x 的 SDK

注意

还有更多相关信息 GitHub。在 AWS 代码示例存储库中查找完整示例，了解如何进行设置和运行。

    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 的详细信息，请参阅 AWS SDK for Java 2.xAPI 参考DeleteTable中的。

获取有关键空间的数据

以下代码示例演示如何获取 Amazon Keyspaces 键空间的相关数据。

适用于 Java 2.x 的 SDK

注意

还有更多相关信息 GitHub。在 AWS 代码示例存储库中查找完整示例，了解如何进行设置和运行。

    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 的详细信息，请参阅 AWS SDK for Java 2.xAPI 参考GetKeyspace中的。

获取有关表的数据

以下代码示例演示如何获取 Amazon Keyspaces 表的相关数据。

适用于 Java 2.x 的 SDK

注意

还有更多相关信息 GitHub。在 AWS 代码示例存储库中查找完整示例，了解如何进行设置和运行。

    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 的详细信息，请参阅 AWS SDK for Java 2.xAPI 参考GetTable中的。

列出键空间

以下代码示例演示如何列出 Amazon Keyspaces 键空间。

适用于 Java 2.x 的 SDK

注意

还有更多相关信息 GitHub。在 AWS 代码示例存储库中查找完整示例，了解如何进行设置和运行。

    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 的详细信息，请参阅 AWS SDK for Java 2.xAPI 参考ListKeyspaces中的。

列出键空间中的表

以下代码示例演示如何列出键空间中的 Amazon Keyspaces 表。

适用于 Java 2.x 的 SDK

注意

还有更多相关信息 GitHub。在 AWS 代码示例存储库中查找完整示例，了解如何进行设置和运行。

    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 的详细信息，请参阅 AWS SDK for Java 2.xAPI 参考ListTables中的。

将表还原到某个时间点

以下代码示例演示如何将 Amazon Keyspaces 表还原到某个时间点。

适用于 Java 2.x 的 SDK

注意

还有更多相关信息 GitHub。在 AWS 代码示例存储库中查找完整示例，了解如何进行设置和运行。

    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);
        }
    }

• 有关 API 的详细信息，请参阅 AWS SDK for Java 2.xAPI 参考RestoreTable中的。

更新表

以下代码示例演示如何更新 Amazon Keyspaces 表。

适用于 Java 2.x 的 SDK

注意

还有更多相关信息 GitHub。在 AWS 代码示例存储库中查找完整示例，了解如何进行设置和运行。

    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);
        }
    }

• 有关 API 的详细信息，请参阅 AWS SDK for Java 2.xAPI 参考UpdateTable中的。

场景

开始使用键空间和表

以下代码示例演示了操作流程：

• 创建键空间和表。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，连接到键空间。

• 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。

适用于 Java 2.x 的 SDK

注意

还有更多相关信息 GitHub。在 AWS 代码示例存储库中查找完整示例，了解如何进行设置和运行。

/**
 * 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 configFilePath = "C:\\AWS\\application.conf";
        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.fromFile(new File(configFilePath));
        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《AWS SDK for Java 2.x API 参考》中的以下主题。

  • CreateKeyspace

  • CreateTable

  • DeleteKeyspace

  • DeleteTable

  • GetKeyspace

  • GetTable

  • ListKeyspaces

  • ListTables

  • RestoreTable

  • UpdateTable