/*
 * Copyright 2018 Google LLC
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     https://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package com.google.cloud.bigtable.data.v2;

import com.google.api.core.ApiFuture;
import com.google.api.core.BetaApi;
import com.google.api.core.InternalApi;
import com.google.api.gax.batching.Batcher;
import com.google.api.gax.rpc.ApiExceptions;
import com.google.api.gax.rpc.ResponseObserver;
import com.google.api.gax.rpc.ServerStream;
import com.google.api.gax.rpc.ServerStreamingCallable;
import com.google.api.gax.rpc.UnaryCallable;
import com.google.cloud.bigtable.data.v2.models.BulkMutation;
import com.google.cloud.bigtable.data.v2.models.ConditionalRowMutation;
import com.google.cloud.bigtable.data.v2.models.Filters;
import com.google.cloud.bigtable.data.v2.models.Filters.Filter;
import com.google.cloud.bigtable.data.v2.models.KeyOffset;
import com.google.cloud.bigtable.data.v2.models.Query;
import com.google.cloud.bigtable.data.v2.models.ReadModifyWriteRow;
import com.google.cloud.bigtable.data.v2.models.Row;
import com.google.cloud.bigtable.data.v2.models.RowAdapter;
import com.google.cloud.bigtable.data.v2.models.RowMutation;
import com.google.cloud.bigtable.data.v2.models.RowMutationEntry;
import com.google.cloud.bigtable.data.v2.stub.EnhancedBigtableStub;
import com.google.protobuf.ByteString;
import java.io.IOException;
import java.util.List;
import javax.annotation.Nonnull;
import javax.annotation.Nullable;

/**
 * Client for reading from and writing to existing Bigtable tables.
 *
 * <p>This class provides the ability to make remote calls to the backing service. Sample code to
 * get started:
 *
 * <pre>{@code
 * // One instance per application.
 * BigtableDataClient client = BigtableDataClient.create("[PROJECT]", "[INSTANCE]")
 *
 * for(Row row : client.readRows(Query.create("[TABLE]")) {
 *   // Do something with row
 * }
 *
 * // Cleanup during application shutdown.
 * client.close();
 * }</pre>
 *
 * <p>Creating a new client is a very expensive operation and should only be done once and shared in
 * an application. However, close() needs to be called on the client object to clean up resources
 * such as threads during application shutdown.
 *
 * <p>The surface of this class includes several types of Java methods for each of the API's
 * methods:
 *
 * <ol>
 *   <li>A "flattened" method, like `readRows()`. With this type of method, the fields of the
 *       request type have been converted into function parameters. It may be the case that not all
 *       fields are available as parameters, and not every API method will have a flattened method
 *       entry point.
 *   <li>A "callable" method, like `readRowsCallable()`. This type of method takes no parameters and
 *       returns an immutable API callable object, which can be used to initiate calls to the
 *       service.
 * </ol>
 *
 * <p>Taking ReadRows as an example for callable:
 *
 * <pre>{@code
 * // These two invocation are equivalent
 * ServerStream<Row> stream1 = client.readRows(query);
 * ServerStream<Row> stream2 = client.readRowsCallable().call(query);
 *
 * // These two invocation are also equivalent
 * client.readRowsAsync(query, observer);
 * client.readRowsCallable().call(query, observer);
 * }</pre>
 *
 * <p>All RPC related errors are represented as subclasses of {@link
 * com.google.api.gax.rpc.ApiException}. For example, a nonexistent table will trigger a {@link
 * com.google.api.gax.rpc.NotFoundException}. Async methods will wrap the error inside the future.
 * Synchronous methods will re-throw the async error but will try to preserve the caller's
 * stacktrace by attaching a suppressed exception at the callsite. This allows callers to use
 * typesafe exceptions, without losing their callsite. Streaming methods (ie. readRows) will
 * re-throw the async exception (like sync methods) when starting iteration.
 *
 * <p>See the individual methods for example code.
 *
 * <p>This class can be customized by passing in a custom instance of BigtableDataSettings to
 * create(). For example:
 *
 * <p>To customize credentials:
 *
 * <pre>{@code
 * BigtableDataSettings settings =
 *     BigtableDataSettings.newBuilder()
 *         .setProjectId("[PROJECT]")
 *         .setInstanceId("[INSTANCE]")
 *         .setCredentialsProvider(FixedCredentialsProvider.create(myCredentials))
 *         .build();
 * BigtableDataClient client = BigtableDataClient.create(settings);
 * }</pre>
 *
 * To customize the endpoint:
 *
 * <pre>{@code
 * BigtableDataSettings.Builder settingsBuilder =
 *     BigtableDataSettings.newBuilder()
 *       .setProjectId("[PROJECT]")
 *       .setInstanceId("[INSTANCE]");
 *
 * settingsBuilder.stubSettings()
 *     .setEndpoint(myEndpoint).build();
 *
 * BigtableDataClient client = BigtableDataClient.create(settings.build());
 * }</pre>
 */
public class BigtableDataClient implements AutoCloseable {
  private final EnhancedBigtableStub stub;

  /**
   * Constructs an instance of BigtableDataClient with default settings.
   *
   * @param projectId The project id of the instance to connect to.
   * @param instanceId The id of the instance to connect to.
   * @return A new client.
   * @throws IOException If any.
   */
  public static BigtableDataClient create(String projectId, String instanceId) throws IOException {
    BigtableDataSettings settings =
        BigtableDataSettings.newBuilder().setProjectId(projectId).setInstanceId(instanceId).build();
    return create(settings);
  }

  /**
   * Constructs an instance of BigtableDataClient, using the given settings. The channels are
   * created based on the settings passed in, or defaults for any settings that are not set.
   */
  public static BigtableDataClient create(BigtableDataSettings settings) throws IOException {
    EnhancedBigtableStub stub = EnhancedBigtableStub.create(settings.getStubSettings());
    return new BigtableDataClient(stub);
  }

  @InternalApi("Visible for testing")
  BigtableDataClient(EnhancedBigtableStub stub) {
    this.stub = stub;
  }

  /**
   * Convenience method for synchronously reading a single row. If the row does not exist, the value
   * will be null.
   *
   * <p>Sample code:
   *
   * <pre>{code
   * try (BigtableDataClient bigtableDataClient = BigtableDataClient.create("[PROJECT]", "[INSTANCE]")) {
   * String tableId = "[TABLE]";
   *
   * Row row = bigtableDataClient.readRow(tableId, ByteString.copyFromUtf8("key"));
   * // Do something with row, for example, display all cells
   * if(row != null) {
   *   System.out.println(row.getKey().toStringUtf8());
   *   for(RowCell cell : row.getCells()) {
   *      System.out.printf("Family: %s   Qualifier: %s   Value: %s", cell.getFamily(),
   *         cell.getQualifier().toStringUtf8(), cell.getValue().toStringUtf8());
   *   }
   * }
   * } catch(ApiException e) {
   *   e.printStackTrace();
   * }
   * }</pre>
   *
   * @throws com.google.api.gax.rpc.ApiException when a serverside error occurs
   */
  public Row readRow(String tableId, ByteString rowKey) {
    return ApiExceptions.callAndTranslateApiException(readRowAsync(tableId, rowKey, null));
  }

  /**
   * Convenience method for synchronously reading a single row. If the row does not exist, the value
   * will be null.
   *
   * <p>Sample code:
   *
   * <pre>{code
   * try (BigtableDataClient bigtableDataClient = BigtableDataClient.create("[PROJECT]", "[INSTANCE]")) {
   *   String tableId = "[TABLE]";
   *
   *   Row row = bigtableDataClient.readRow(tableId, "key");
   *   // Do something with row, for example, display all cells
   *   if(row != null) {
   *     System.out.println(row.getKey().toStringUtf8());
   *      for(RowCell cell : row.getCells()) {
   *        System.out.printf("Family: %s   Qualifier: %s   Value: %s", cell.getFamily(),
   *           cell.getQualifier().toStringUtf8(), cell.getValue().toStringUtf8());
   *      }
   *   }
   * } catch(ApiException e) {
   *   e.printStackTrace();
   * }
   * }</pre>
   *
   * @throws com.google.api.gax.rpc.ApiException when a serverside error occurs
   */
  public Row readRow(String tableId, String rowKey) {
    return ApiExceptions.callAndTranslateApiException(
        readRowAsync(tableId, ByteString.copyFromUtf8(rowKey), null));
  }

  /**
   * Convenience method for synchronously reading a single row. If the row does not exist, the value
   * will be null.
   *
   * <p>Sample code:
   *
   * <pre>{@code
   * try (BigtableDataClient bigtableDataClient = BigtableDataClient.create("[PROJECT]", "[INSTANCE]")) {
   *   String tableId = "[TABLE]";
   *
   *  // Build the filter expression
   *  Filter filter = FILTERS.chain()
   *         .filter(FILTERS.qualifier().regex("prefix.*"))
   *         .filter(FILTERS.limit().cellsPerRow(10));
   *
   *   Row row = bigtableDataClient.readRow(tableId, "key", filter);
   *   // Do something with row, for example, display all cells
   *   if(row != null) {
   *     System.out.println(row.getKey().toStringUtf8());
   *      for(RowCell cell : row.getCells()) {
   *        System.out.printf("Family: %s   Qualifier: %s   Value: %s", cell.getFamily(),
   *           cell.getQualifier().toStringUtf8(), cell.getValue().toStringUtf8());
   *      }
   *   }
   * } catch(ApiException e) {
   *   e.printStackTrace();
   * }
   * }</pre>
   *
   * @throws com.google.api.gax.rpc.ApiException when a serverside error occurs
   */
  public Row readRow(String tableId, String rowKey, @Nullable Filter filter) {
    return ApiExceptions.callAndTranslateApiException(
        readRowAsync(tableId, ByteString.copyFromUtf8(rowKey), filter));
  }

  /**
   * Convenience method for synchronously reading a single row. If the row does not exist, the value
   * will be null.
   *
   * <p>Sample code:
   *
   * <pre>{@code
   * try (BigtableDataClient bigtableDataClient = BigtableDataClient.create("[PROJECT]", "[INSTANCE]")) {
   *   String tableId = "[TABLE]";
   *
   *  // Build the filter expression
   *  Filter filter = FILTERS.chain()
   *         .filter(FILTERS.qualifier().regex("prefix.*"))
   *         .filter(FILTERS.limit().cellsPerRow(10));
   *
   *   Row row = bigtableDataClient.readRow(tableId, ByteString.copyFromUtf8("key"), filter);
   *   // Do something with row, for example, display all cells
   *   if(row != null) {
   *     System.out.println(row.getKey().toStringUtf8());
   *      for(RowCell cell : row.getCells()) {
   *        System.out.printf("Family: %s   Qualifier: %s   Value: %s", cell.getFamily(),
   *           cell.getQualifier().toStringUtf8(), cell.getValue().toStringUtf8());
   *      }
   *   }
   * } catch(ApiException e) {
   *   e.printStackTrace();
   * }
   * }</pre>
   *
   * @throws com.google.api.gax.rpc.ApiException when a serverside error occurs
   */
  public Row readRow(String tableId, ByteString rowKey, @Nullable Filter filter) {
    return ApiExceptions.callAndTranslateApiException(readRowAsync(tableId, rowKey, filter));
  }

  /**
   * Convenience method for asynchronously reading a single row. If the row does not exist, the
   * future's value will be null.
   *
   * <p>Sample code:
   *
   * <pre>{@code
   * try (BigtableDataClient bigtableDataClient = BigtableDataClient.create("[PROJECT]", "[INSTANCE]")) {
   *   String tableId = "[TABLE]";
   *
   *   ApiFuture<Row> futureResult = bigtableDataClient.readRowAsync(tableId,  "key");
   *
   *   ApiFutures.addCallback(futureResult, new ApiFutureCallback<Row>() {
   *     public void onFailure(Throwable t) {
   *       if (t instanceof NotFoundException) {
   *         System.out.println("Tried to read a non-existent table");
   *       } else {
   *         t.printStackTrace();
   *       }
   *     }
   *     public void onSuccess(Row result) {
   *       if (result != null) {
   *          System.out.println("Got row: " + result);
   *       }
   *     }
   *   }, MoreExecutors.directExecutor());
   * }
   * }</pre>
   */
  public ApiFuture<Row> readRowAsync(String tableId, String rowKey) {
    return readRowAsync(tableId, ByteString.copyFromUtf8(rowKey), null);
  }

  /**
   * Convenience method for asynchronously reading a single row. If the row does not exist, the
   * future's value will be null.
   *
   * <p>Sample code:
   *
   * <pre>{@code
   * try (BigtableDataClient bigtableDataClient = BigtableDataClient.create("[PROJECT]", "[INSTANCE]")) {
   *   String tableId = "[TABLE]";
   *
   *   ApiFuture<Row> futureResult = bigtableDataClient.readRowAsync(tableId,  ByteString.copyFromUtf8("key"));
   *
   *   ApiFutures.addCallback(futureResult, new ApiFutureCallback<Row>() {
   *     public void onFailure(Throwable t) {
   *       if (t instanceof NotFoundException) {
   *         System.out.println("Tried to read a non-existent table");
   *       } else {
   *         t.printStackTrace();
   *       }
   *     }
   *     public void onSuccess(Row row) {
   *       if (result != null) {
   *          System.out.println("Got row: " + result);
   *       }
   *     }
   *   }, MoreExecutors.directExecutor());
   * }
   * }</pre>
   */
  public ApiFuture<Row> readRowAsync(String tableId, ByteString rowKey) {
    return readRowAsync(tableId, rowKey, null);
  }

  /**
   * Convenience method for asynchronously reading a single row. If the row does not exist, the
   * future's value will be null.
   *
   * <p>Sample code:
   *
   * <pre>{@code
   * try (BigtableDataClient bigtableDataClient = BigtableDataClient.create("[PROJECT]", "[INSTANCE]")) {
   *   String tableId = "[TABLE]";
   *
   *  // Build the filter expression
   *   Filters.Filter filter = FILTERS.chain()
   *         .filter(FILTERS.qualifier().regex("prefix.*"))
   *         .filter(FILTERS.limit().cellsPerRow(10));
   *
   *   ApiFuture<Row> futureResult = bigtableDataClient.readRowAsync(tableId, "key", filter);
   *
   *   ApiFutures.addCallback(futureResult, new ApiFutureCallback<Row>() {
   *     public void onFailure(Throwable t) {
   *       if (t instanceof NotFoundException) {
   *         System.out.println("Tried to read a non-existent table");
   *       } else {
   *         t.printStackTrace();
   *       }
   *     }
   *     public void onSuccess(Row row) {
   *       if (result != null) {
   *          System.out.println("Got row: " + result);
   *       }
   *     }
   *   }, MoreExecutors.directExecutor());
   * }
   * }</pre>
   */
  public ApiFuture<Row> readRowAsync(String tableId, String rowKey, @Nullable Filter filter) {
    return readRowAsync(tableId, ByteString.copyFromUtf8(rowKey), filter);
  }

  /**
   * Convenience method for asynchronously reading a single row. If the row does not exist, the
   * future's value will be null.
   *
   * <p>Sample code:
   *
   * <pre>{@code
   * try (BigtableDataClient bigtableDataClient = BigtableDataClient.create("[PROJECT]", "[INSTANCE]")) {
   *   String tableId = "[TABLE]";
   *
   *  // Build the filter expression
   *  Filters.Filter filter = FILTERS.chain()
   *         .filter(FILTERS.qualifier().regex("prefix.*"))
   *         .filter(FILTERS.limit().cellsPerRow(10));
   *
   *   ApiFuture<Row> futureResult = bigtableDataClient.readRowAsync(tableId, ByteString.copyFromUtf8("key"), filter);
   *
   *   ApiFutures.addCallback(futureResult, new ApiFutureCallback<Row>() {
   *     public void onFailure(Throwable t) {
   *       if (t instanceof NotFoundException) {
   *         System.out.println("Tried to read a non-existent table");
   *       } else {
   *         t.printStackTrace();
   *       }
   *     }
   *     public void onSuccess(Row row) {
   *       if (result != null) {
   *          System.out.println("Got row: " + result);
   *       }
   *     }
   *   }, MoreExecutors.directExecutor());
   * }
   * }</pre>
   */
  public ApiFuture<Row> readRowAsync(String tableId, ByteString rowKey, @Nullable Filter filter) {
    Query query = Query.create(tableId).rowKey(rowKey);
    if (filter != null) {
      query = query.filter(filter);
    }
    return readRowCallable().futureCall(query);
  }

  /**
   * Reads a single row. The returned callable object allows for customization of api invocation.
   *
   * <p>Sample code:
   *
   * <pre>{@code
   * try (BigtableDataClient bigtableDataClient = BigtableDataClient.create("[PROJECT]", "[INSTANCE]")) {
   *   String tableId = "[TABLE]";
   *
   *   Query query = Query.create(tableId)
   *          .rowKey("[KEY]")
   *          .filter(FILTERS.qualifier().regex("[COLUMN PREFIX].*"));
   *
   *   // Synchronous invocation
   *   try {
   *     Row row = bigtableDataClient.readRowCallable().call(query);
   *     if (row == null) {
   *       System.out.println("Row not found");
   *     }
   *   } catch (RuntimeException e) {
   *     e.printStackTrace();
   *   }
   *
   *   // Asynchronous invocation
   *   ApiFuture<Row> rowFuture = bigtableDataClient.readRowCallable().futureCall(query);
   *
   *   ApiFutures.addCallback(rowFuture, new ApiFutureCallback<Row>() {
   *     public void onFailure(Throwable t) {
   *       if (t instanceof NotFoundException) {
   *         System.out.println("Tried to read a non-existent table");
   *       } else {
   *         t.printStackTrace();
   *       }
   *     }
   *     public void onSuccess(Row row) {
   *       if (row == null) {
   *         System.out.println("Row not found");
   *       }
   *     }
   *   }, MoreExecutors.directExecutor());
   * }
   * }</pre>
   *
   * @see UnaryCallable For call styles.
   * @see Query For query options.
   * @see com.google.cloud.bigtable.data.v2.models.Filters For the filter building DSL.
   */
  public UnaryCallable<Query, Row> readRowCallable() {
    return stub.readRowCallable();
  }

  /**
   * Reads a single row. This callable allows for customization of the logical representation of a
   * row. It's meant for advanced use cases.
   *
   * <p>Sample code:
   *
   * <pre>{@code
   * try (BigtableDataClient bigtableDataClient = BigtableDataClient.create("[PROJECT]", "[INSTANCE]")) {
   *   String tableId = "[TABLE]";
   *
   *   Query query = Query.create(tableId)
   *          .rowKey("[KEY]")
   *          .filter(FILTERS.qualifier().regex("[COLUMN PREFIX].*"));
   *
   *   // Synchronous invocation
   *   CustomRow row = bigtableDataClient.readRowCallable(new CustomRowAdapter()).call(query));
   *   // Do something with row
   * }
   * }</pre>
   *
   * @see ServerStreamingCallable For call styles.
   * @see Query For query options.
   * @see com.google.cloud.bigtable.data.v2.models.Filters For the filter building DSL.
   */
  public <RowT> UnaryCallable<Query, RowT> readRowCallable(RowAdapter<RowT> rowAdapter) {
    return stub.createReadRowCallable(rowAdapter);
  }

  /**
   * Convenience method for synchronously streaming the results of a {@link Query}.
   *
   * <p>Sample code:
   *
   * <pre>{@code
   * // Import the filter DSL
   * import static com.google.cloud.bigtable.data.v2.models.Filters.FILTERS;
   *
   * try (BigtableDataClient bigtableDataClient = BigtableDataClient.create("[PROJECT]", "[INSTANCE]")) {
   *   String tableId = "[TABLE]";
   *
   *   Query query = Query.create(tableId)
   *          .range("[START KEY]", "[END KEY]")
   *          .filter(FILTERS.qualifier().regex("[COLUMN PREFIX].*"));
   *
   *   try {
   *     ServerStream<Row> stream = bigtableDataClient.readRows(query);
   *     int count = 0;
   *
   *     // Iterator style
   *     for (Row row : stream) {
   *       if (++count > 10) {
   *         stream.cancel();
   *         break;
   *       }
   *       // Do something with row
   *     }
   *   } catch (NotFoundException e) {
   *     System.out.println("Tried to read a non-existent table");
   *   } catch (RuntimeException e) {
   *     e.printStackTrace();
   *   }
   * }
   * }</pre>
   *
   * @see ServerStreamingCallable For call styles.
   * @see Query For query options.
   * @see com.google.cloud.bigtable.data.v2.models.Filters For the filter building DSL.
   */
  public ServerStream<Row> readRows(Query query) {
    return readRowsCallable().call(query);
  }

  /**
   * Convenience method for asynchronously streaming the results of a {@link Query}.
   *
   * <p>Sample code:
   *
   * <pre>{@code
   * try (BigtableDataClient bigtableDataClient = BigtableDataClient.create("[PROJECT]", "[INSTANCE]")) {
   *   String tableId = "[TABLE]";
   *
   *   Query query = Query.create(tableId)
   *          .range("[START KEY]", "[END KEY]")
   *          .filter(FILTERS.qualifier().regex("[COLUMN PREFIX].*"));
   *
   *   bigtableDataClient.readRowsAsync(query, new ResponseObserver<Row>() {
   *     StreamController controller;
   *     int count = 0;
   *
   *     public void onStart(StreamController controller) {
   *       this.controller = controller;
   *     }
   *     public void onResponse(Row row) {
   *       if (++count > 10) {
   *         controller.cancel();
   *         return;
   *       }
   *       // Do something with Row
   *     }
   *     public void onError(Throwable t) {
   *       if (t instanceof NotFoundException) {
   *         System.out.println("Tried to read a non-existent table");
   *       } else {
   *         t.printStackTrace();
   *       }
   *     }
   *     public void onComplete() {
   *       // Handle stream completion
   *     }
   *   });
   * }
   * }</pre>
   */
  public void readRowsAsync(Query query, ResponseObserver<Row> observer) {
    readRowsCallable().call(query, observer);
  }

  /**
   * Streams back the results of the query. The returned callable object allows for customization of
   * api invocation.
   *
   * <p>Sample code:
   *
   * <pre>{@code
   * try (BigtableDataClient bigtableDataClient = BigtableDataClient.create("[PROJECT]", "[INSTANCE]")) {
   *   String tableId = "[TABLE]";
   *
   *   Query query = Query.create(tableId)
   *          .range("[START KEY]", "[END KEY]")
   *          .filter(FILTERS.qualifier().regex("[COLUMN PREFIX].*"));
   *
   *   // Iterator style
   *   try {
   *     for(Row row : bigtableDataClient.readRowsCallable().call(query)) {
   *       // Do something with row
   *     }
   *   } catch (NotFoundException e) {
   *     System.out.println("Tried to read a non-existent table");
   *   } catch (RuntimeException e) {
   *     e.printStackTrace();
   *   }
   *
   *   // Sync style
   *   try {
   *     List<Row> rows = bigtableDataClient.readRowsCallable().all().call(query);
   *   } catch (NotFoundException e) {
   *     System.out.println("Tried to read a non-existent table");
   *   } catch (RuntimeException e) {
   *     e.printStackTrace();
   *   }
   *
   *   // Point look up
   *   ApiFuture<Row> rowFuture = bigtableDataClient.readRowsCallable().first().futureCall(query);
   *
   *   ApiFutures.addCallback(rowFuture, new ApiFutureCallback<Row>() {
   *     public void onFailure(Throwable t) {
   *       if (t instanceof NotFoundException) {
   *         System.out.println("Tried to read a non-existent table");
   *       } else {
   *         t.printStackTrace();
   *       }
   *     }
   *     public void onSuccess(Row result) {
   *       System.out.println("Got row: " + result);
   *     }
   *   }, MoreExecutors.directExecutor());
   *
   *   // etc
   * }
   * }</pre>
   *
   * @see ServerStreamingCallable For call styles.
   * @see Query For query options.
   * @see com.google.cloud.bigtable.data.v2.models.Filters For the filter building DSL.
   */
  public ServerStreamingCallable<Query, Row> readRowsCallable() {
    return stub.readRowsCallable();
  }

  /**
   * Streams back the results of the query. This callable allows for customization of the logical
   * representation of a row. It's meant for advanced use cases.
   *
   * <p>Sample code:
   *
   * <pre>{@code
   * try (BigtableDataClient bigtableDataClient = BigtableDataClient.create("[PROJECT]", "[INSTANCE]")) {
   *   String tableId = "[TABLE]";
   *
   *   Query query = Query.create(tableId)
   *          .range("[START KEY]", "[END KEY]")
   *          .filter(FILTERS.qualifier().regex("[COLUMN PREFIX].*"));
   *
   *   // Iterator style
   *   try {
   *     for(CustomRow row : bigtableDataClient.readRowsCallable(new CustomRowAdapter()).call(query)) {
   *       // Do something with row
   *     }
   *   } catch (NotFoundException e) {
   *     System.out.println("Tried to read a non-existent table");
   *   } catch (RuntimeException e) {
   *     e.printStackTrace();
   *   }
   * }
   * }</pre>
   *
   * @see ServerStreamingCallable For call styles.
   * @see Query For query options.
   * @see com.google.cloud.bigtable.data.v2.models.Filters For the filter building DSL.
   */
  public <RowT> ServerStreamingCallable<Query, RowT> readRowsCallable(RowAdapter<RowT> rowAdapter) {
    return stub.createReadRowsCallable(rowAdapter);
  }

  /**
   * Convenience method to synchronously return a sample of row keys in the table. The returned row
   * keys will delimit contiguous sections of the table of approximately equal size, which can be
   * used to break up the data for distributed tasks like mapreduces.
   *
   * <p>Sample code:
   *
   * <pre>{@code
   * try (BigtableDataClient bigtableDataClient = BigtableDataClient.create("[PROJECT]", "[INSTANCE]")) {
   *   String tableId = "[TABLE_ID]";
   *
   *   List<KeyOffset> keyOffsets = bigtableDataClient.sampleRowKeys(tableId);
   *   for(KeyOffset keyOffset : keyOffsets) {
   *   // Do something with keyOffset
   *   }
   * } catch(ApiException e) {
   *   e.printStackTrace();
   * }
   * }</pre>
   *
   * @throws com.google.api.gax.rpc.ApiException when a serverside error occurs
   */
  public List<KeyOffset> sampleRowKeys(String tableId) {
    return ApiExceptions.callAndTranslateApiException(sampleRowKeysAsync(tableId));
  }

  /**
   * Convenience method to asynchronously return a sample of row keys in the table. The returned row
   * keys will delimit contiguous sections of the table of approximately equal size, which can be
   * used to break up the data for distributed tasks like mapreduces.
   *
   * <p>Sample code:
   *
   * <pre>{@code
   * try (BigtableClient bigtableDataClient = BigtableClient.create("[PROJECT]", "[INSTANCE]")) {
   *   ApiFuture<List<KeyOffset>> keyOffsetsFuture = bigtableClient.sampleRowKeysAsync("[TABLE]");
   *
   *   ApiFutures.addCallback(keyOffsetsFuture, new ApiFutureCallback<List<KeyOffset>>() {
   *     public void onFailure(Throwable t) {
   *       if (t instanceof NotFoundException) {
   *         System.out.println("Tried to sample keys of a non-existent table");
   *       } else {
   *         t.printStackTrace();
   *       }
   *     }
   *     public void onSuccess(List<KeyOffset> keyOffsets) {
   *       System.out.println("Got key offsets: " + keyOffsets);
   *     }
   *   }, MoreExecutors.directExecutor());
   * }
   * }</pre>
   */
  public ApiFuture<List<KeyOffset>> sampleRowKeysAsync(String tableId) {
    return sampleRowKeysCallable().futureCall(tableId);
  }

  /**
   * Returns a sample of row keys in the table. The returned row keys will delimit contiguous
   * sections of the table of approximately equal size, which can be used to break up the data for
   * distributed tasks like mapreduces. The returned callable object allows for customization of api
   * invocation.
   *
   * <p>Sample code:
   *
   * <pre>{@code
   * try (BigtableDataClient bigtableDataClient = BigtableDataClient.create("[PROJECT]", "[INSTANCE]")) {
   *   // Synchronous invocation
   *   try {
   *     List<KeyOffset> keyOffsets = bigtableDataClient.sampleRowKeysCallable().call("[TABLE]");
   *   } catch (NotFoundException e) {
   *     System.out.println("Tried to sample keys of a non-existent table");
   *   } catch (RuntimeException e) {
   *     e.printStackTrace();
   *   }
   *
   *   // Asynchronous invocation
   *   ApiFuture<List<KeyOffset>> keyOffsetsFuture = bigtableDataClient.sampleRowKeysCallable().futureCall("[TABLE]");
   *
   *   ApiFutures.addCallback(keyOffsetsFuture, new ApiFutureCallback<List<KeyOffset>>() {
   *     public void onFailure(Throwable t) {
   *       if (t instanceof NotFoundException) {
   *         System.out.println("Tried to sample keys of a non-existent table");
   *       } else {
   *         t.printStackTrace();
   *       }
   *     }
   *     public void onSuccess(List<KeyOffset> keyOffsets) {
   *       System.out.println("Got key offsets: " + keyOffsets);
   *     }
   *   }, MoreExecutors.directExecutor());
   * }
   * }</pre>
   */
  public UnaryCallable<String, List<KeyOffset>> sampleRowKeysCallable() {
    return stub.sampleRowKeysCallable();
  }

  /**
   * Convenience method to synchronously mutate a single row atomically. Cells already present in
   * the row are left unchanged unless explicitly changed by the {@link RowMutation}.
   *
   * <p>Sample code:
   *
   * <pre>{@code
   * try (BigtableDataClient bigtableDataClient = BigtableDataClient.create("[PROJECT]", "[INSTANCE]")) {
   *   RowMutation mutation = RowMutation.create("[TABLE]", "[ROW KEY]")
   *     .setCell("[FAMILY NAME]", "[QUALIFIER]", "[VALUE]");
   *
   *   bigtableDataClient.mutateRow(mutation);
   * } catch(ApiException e) {
   *   e.printStackTrace();
   * }
   * }</pre>
   *
   * @throws com.google.api.gax.rpc.ApiException when a serverside error occurs
   */
  public void mutateRow(RowMutation rowMutation) {
    ApiExceptions.callAndTranslateApiException(mutateRowAsync(rowMutation));
  }

  /**
   * Convenience method to asynchronously mutate a single row atomically. Cells already present in
   * the row are left unchanged unless explicitly changed by the {@link RowMutation}.
   *
   * <p>Sample code:
   *
   * <pre>{@code
   * try (BigtableDataClient bigtableDataClient = BigtableDataClient.create("[PROJECT]", "[INSTANCE]")) {
   *   RowMutation mutation = RowMutation.create("[TABLE]", "[ROW KEY]")
   *     .setCell("[FAMILY NAME]", "[QUALIFIER]", "[VALUE]");
   *
   *   ApiFuture<Void> future = bigtableDataClient.mutateRowAsync(mutation);
   *
   *   ApiFutures.addCallback(future, new ApiFutureCallback<Void>() {
   *     public void onFailure(Throwable t) {
   *       if (t instanceof NotFoundException) {
   *         System.out.println("Tried to mutate a non-existent table");
   *       } else {
   *         t.printStackTrace();
   *       }
   *     }
   *     public void onSuccess(Void ignored) {
   *       System.out.println("Successfully applied mutation");
   *     }
   *   }, MoreExecutors.directExecutor());
   * }
   * }</pre>
   */
  public ApiFuture<Void> mutateRowAsync(RowMutation rowMutation) {
    return mutateRowCallable().futureCall(rowMutation);
  }

  /**
   * Mutates a single row atomically. Cells already present in the row are left unchanged unless
   * explicitly changed by the {@link RowMutation}.
   *
   * <p>Sample code:
   *
   * <pre>{@code
   * try (BigtableDataClient bigtableDataClient = BigtableDataClient.create("[PROJECT]", "[INSTANCE]")) {
   *   RowMutation mutation = RowMutation.create("[TABLE]", "[ROW KEY]")
   *     .setCell("[FAMILY NAME]", "[QUALIFIER]", "[VALUE]");
   *
   *   // Sync style
   *   try {
   *     bigtableDataClient.mutateRowCallable().call(mutation);
   *   } catch (NotFoundException e) {
   *     System.out.println("Tried to mutate a non-existent table");
   *   } catch (RuntimeException e) {
   *     e.printStackTrace();
   *   }
   * }
   * }</pre>
   */
  public UnaryCallable<RowMutation, Void> mutateRowCallable() {
    return stub.mutateRowCallable();
  }

  /**
   * Convenience method to mutate multiple rows in a batch. Each individual row is mutated
   * atomically as in MutateRow, but the entire batch is not executed atomically. This method
   * expects the mutations to be pre-batched.
   *
   * <p>Sample code:
   *
   * <pre>{@code
   * try (BigtableDataClient bigtableDataClient = BigtableDataClient.create("[PROJECT]", "[INSTANCE]")) {
   *   BulkMutation batch = BulkMutation.create("[TABLE]");
   *   for (String someValue : someCollection) {
   *     batch.add("[ROW KEY]", Mutation.create().setCell("[FAMILY NAME]", "[QUALIFIER]", "[VALUE]"));
   *   }
   *   bigtableDataClient.bulkMutateRows(batch);
   * } catch(ApiException e) {
   *   e.printStackTrace();
   * } catch(MutateRowsException e) {
   *   e.printStackTrace();
   * }
   * }</pre>
   *
   * @throws com.google.api.gax.rpc.ApiException when a serverside error occurs
   * @throws com.google.cloud.bigtable.data.v2.models.MutateRowsException if any of the entries
   *     failed to be applied
   */
  public void bulkMutateRows(BulkMutation mutation) {
    ApiExceptions.callAndTranslateApiException(bulkMutateRowsAsync(mutation));
  }

  /**
   * Mutates multiple rows in a batch. Each individual row is mutated atomically as in MutateRow,
   * but the entire batch is not executed atomically.
   *
   * <p>Sample Code:
   *
   * <pre>{@code
   * try (BigtableDataClient bigtableDataClient = BigtableDataClient.create("[PROJECT]", "[INSTANCE]")) {
   *   try (Batcher<RowMutationEntry, Void> batcher = bigtableDataClient.newBulkMutationBatcher("[TABLE]")) {
   *     for (String someValue : someCollection) {
   *       ApiFuture<Void> entryFuture =
   *           batcher.add(
   *               RowMutationEntry.create("[ROW KEY]")
   *                   .setCell("[FAMILY NAME]", "[QUALIFIER]", "[VALUE]"));
   *     }
   *
   *     // Blocks until mutations are applied on all submitted row entries.
   *     batcher.flush();
   *   }
   *   // Before `batcher` is closed, all remaining(If any) mutations are applied.
   * }
   * }</pre>
   */
  @BetaApi("This surface is likely to change as the batching surface evolves.")
  public Batcher<RowMutationEntry, Void> newBulkMutationBatcher(@Nonnull String tableId) {
    return stub.newMutateRowsBatcher(tableId);
  }

  /**
   * Reads rows for given tableId in a batch. If the row does not exist, the value will be null.
   * This operation should be called with in a single thread.
   *
   * <p>Sample Code:
   *
   * <pre>{@code
   * try (BigtableDataClient bigtableDataClient = BigtableDataClient.create("[PROJECT]", "[INSTANCE]")) {
   *   List<ApiFuture<Row>> rows = new ArrayList<>();
   *
   *   try (Batcher<ByteString, Row> batcher = bigtableDataClient.newBulkReadRowsBatcher("[TABLE]")) {
   *     for (String someValue : someCollection) {
   *       ApiFuture<Row> rowFuture =
   *           batcher.add(ByteString.copyFromUtf8("[ROW KEY]"));
   *       rows.add(rowFuture);
   *     }
   *
   *     // [Optional] Sends collected elements for batching asynchronously.
   *     batcher.sendOutstanding();
   *
   *     // [Optional] Invokes sendOutstanding() and awaits until all pending entries are resolved.
   *     batcher.flush();
   *   }
   *   // batcher.close() invokes `flush()` which will in turn invoke `sendOutstanding()` with await for
   *   pending batches until its resolved.
   *
   *   List<Row> actualRows = ApiFutures.allAsList(rows).get();
   * }
   * }</pre>
   */
  public Batcher<ByteString, Row> newBulkReadRowsBatcher(String tableId) {
    return newBulkReadRowsBatcher(tableId, null);
  }

  /**
   * Reads rows for given tableId and filter criteria in a batch. If the row does not exist, the
   * value will be null. This operation should be called with in a single thread.
   *
   * <p>Sample Code:
   *
   * <pre>{@code
   * try (BigtableDataClient bigtableDataClient = BigtableDataClient.create("[PROJECT]", "[INSTANCE]")) {
   *
   *  // Build the filter expression
   *  Filter filter = FILTERS.chain()
   *         .filter(FILTERS.key().regex("prefix.*"))
   *         .filter(FILTERS.limit().cellsPerRow(10));
   *
   *   List<ApiFuture<Row>> rows = new ArrayList<>();
   *
   *   try (Batcher<ByteString, Row> batcher = bigtableDataClient.newBulkReadRowsBatcher("[TABLE]", filter)) {
   *     for (String someValue : someCollection) {
   *       ApiFuture<Row> rowFuture =
   *           batcher.add(ByteString.copyFromUtf8("[ROW KEY]"));
   *       rows.add(rowFuture);
   *     }
   *
   *     // [Optional] Sends collected elements for batching asynchronously.
   *     batcher.sendOutstanding();
   *
   *     // [Optional] Invokes sendOutstanding() and awaits until all pending entries are resolved.
   *     batcher.flush();
   *   }
   *   // batcher.close() invokes `flush()` which will in turn invoke `sendOutstanding()` with await for
   *   pending batches until its resolved.
   *
   *   List<Row> actualRows = ApiFutures.allAsList(rows).get();
   * }
   * }</pre>
   */
  public Batcher<ByteString, Row> newBulkReadRowsBatcher(
      String tableId, @Nullable Filters.Filter filter) {
    Query query = Query.create(tableId);
    if (filter != null) {
      query = query.filter(filter);
    }
    return stub.newBulkReadRowsBatcher(query);
  }

  /**
   * Convenience method to mutate multiple rows in a batch. Each individual row is mutated
   * atomically as in MutateRow, but the entire batch is not executed atomically. This method
   * expects the mutations to be pre-batched.
   *
   * <p>Sample code:
   *
   * <pre>{@code
   * try (BigtableClient bigtableClient = BigtableClient.create("[PROJECT]", "[INSTANCE]")) {
   *   BulkMutation batch = BulkMutation.create("[TABLE]");
   *   for (String someValue : someCollection) {
   *     ApiFuture<Void> entryFuture = batch.add("[ROW KEY]",
   *       Mutation.create().setCell("[FAMILY NAME]", "[QUALIFIER]", "[VALUE]"));
   *   }
   *   ApiFuture<Void> resultFuture = bigtableDataClient.bulkMutateRowsAsync(batch);
   *
   *   ApiFutures.addCallback(resultFuture, new ApiFutureCallback<Void>() {
   *     public void onFailure(Throwable t) {
   *       if (t instanceof BulkMutationFailure) {
   *         System.out.println("Some entries failed to apply");
   *       } else {
   *         t.printStackTrace();
   *       }
   *     }
   *     public void onSuccess(Void ignored) {
   *       System.out.println("Successfully applied all mutation");
   *     }
   *   }, MoreExecutors.directExecutor());
   * }
   * }</pre>
   */
  public ApiFuture<Void> bulkMutateRowsAsync(BulkMutation mutation) {
    return bulkMutationCallable().futureCall(mutation);
  }

  /**
   * Mutates multiple rows in a batch. Each individual row is mutated atomically as in MutateRow,
   * but the entire batch is not executed atomically. This method expects the mutations to be
   * pre-batched.
   *
   * <p>Sample code:
   *
   * <pre>{@code
   * try (BigtableDataClient bigtableDataClient = BigtableDataClient.create("[PROJECT]", "[INSTANCE]")) {
   *   BulkMutation batch = BulkMutation.create("[TABLE]");
   *   for (String someValue : someCollection) {
   *     ApiFuture<Void> entryFuture = batch.add("[ROW KEY]",
   *       Mutation.create().setCell("[FAMILY NAME]", "[QUALIFIER]", "[VALUE]");
   *   }
   *   bigtableDataClient.bulkMutationCallable().call(batch);
   * }
   * }</pre>
   */
  public UnaryCallable<BulkMutation, Void> bulkMutationCallable() {
    return stub.bulkMutateRowsCallable();
  }

  /**
   * Convenience method to synchronously mutate a row atomically based on the output of a filter.
   *
   * <p>Sample code:
   *
   * <pre>{@code
   * try (BigtableDataClient bigtableDataClient = BigtableDataClient.create("[PROJECT]", "[INSTANCE]")) {
   *   ConditionalRowMutation mutation = ConditionalRowMutation.create("[TABLE]", "[KEY]")
   *     .condition(FILTERS.value().regex("old-value"))
   *     .then(
   *       Mutation.create()
   *         .setCell("[FAMILY]", "[QUALIFIER]", "[VALUE]")
   *       );
   *
   *   Boolean result = bigtableDataClient.checkAndMutateRow(mutation);
   * } catch(ApiException e) {
   *   e.printStackTrace();
   * }
   * }</pre>
   *
   * @throws com.google.api.gax.rpc.ApiException when a serverside error occurs
   */
  public Boolean checkAndMutateRow(ConditionalRowMutation mutation) {
    return ApiExceptions.callAndTranslateApiException(checkAndMutateRowAsync(mutation));
  }

  /**
   * Convenience method to asynchronously mutate a row atomically based on the output of a filter.
   *
   * <p>Sample code:
   *
   * <pre>{@code
   * try (BigtableDataClient bigtableDataClient = BigtableDataClient.create("[PROJECT]", "[INSTANCE]")) {
   *   ConditionalRowMutation mutation = ConditionalRowMutation.create("[TABLE]", "[KEY]")
   *     .condition(FILTERS.value().regex("old-value"))
   *     .then(
   *       Mutation.create()
   *         .setCell("[FAMILY]", "[QUALIFIER]", "[VALUE]")
   *       );
   *
   *   ApiFuture<Boolean> future = bigtableDataClient.checkAndMutateRowAsync(mutation);
   *
   *   ApiFutures.addCallback(future, new ApiFutureCallback<Boolean>() {
   *     public void onFailure(Throwable t) {
   *       if (t instanceof NotFoundException) {
   *         System.out.println("Tried to mutate a non-existent table");
   *       } else {
   *         t.printStackTrace();
   *       }
   *     }
   *     public void onSuccess(Boolean wasApplied) {
   *       System.out.println("Row was modified: " + wasApplied);
   *     }
   *   }, MoreExecutors.directExecutor());
   * }
   * }</pre>
   */
  public ApiFuture<Boolean> checkAndMutateRowAsync(ConditionalRowMutation mutation) {
    return checkAndMutateRowCallable().futureCall(mutation);
  }

  /**
   * Mutates a row atomically based on the output of a filter.
   *
   * <p>Sample code:
   *
   * <pre>{@code
   * try (BigtableDataClient bigtableDataClient = BigtableDataClient.create("[PROJECT]", "[INSTANCE]")) {
   *   ConditionalRowMutation mutation = ConditionalRowMutation.create("[TABLE]", "[KEY]")
   *     .condition(FILTERS.value().regex("old-value"))
   *     .then(
   *       Mutation.create()
   *         .setCell("[FAMILY]", "[QUALIFIER]", "[VALUE]")
   *       );
   *
   *   // Sync style
   *   try {
   *     boolean success = bigtableDataClient.checkAndMutateRowCallable().call(mutation);
   *     if (!success) {
   *       System.out.println("Row did not match conditions");
   *     }
   *   } catch (NotFoundException e) {
   *     System.out.println("Tried to mutate a non-existent table");
   *   } catch (RuntimeException e) {
   *     e.printStackTrace();
   *   }
   * }
   * }</pre>
   */
  public UnaryCallable<ConditionalRowMutation, Boolean> checkAndMutateRowCallable() {
    return stub.checkAndMutateRowCallable();
  }

  /**
   * Convenience method that synchronously modifies a row atomically on the server. The method reads
   * the latest existing timestamp and value from the specified columns and writes a new entry. The
   * new value for the timestamp is the greater of the existing timestamp or the current server
   * time. The method returns the new contents of all modified cells.
   *
   * <p>Sample code:
   *
   * <pre>{@code
   * try (BigtableDataClient bigtableDataClient = BigtableDataClient.create("[PROJECT]", "[INSTANCE]")) {
   *   ReadModifyWriteRow mutation = ReadModifyWriteRow.create("[TABLE]", "[KEY]")
   *     .increment("[FAMILY]", "[QUALIFIER]", 1)
   *     .append("[FAMILY2]", "[QUALIFIER2]", "suffix");
   *
   *   Row success = bigtableDataClient.readModifyWriteRow(mutation);
   * } catch(ApiException e) {
   *   e.printStackTrace();
   * }
   * }</pre>
   *
   * @throws com.google.api.gax.rpc.ApiException when a serverside error occurs
   */
  public Row readModifyWriteRow(ReadModifyWriteRow mutation) {
    return ApiExceptions.callAndTranslateApiException(readModifyWriteRowAsync(mutation));
  }

  /**
   * Convenience method that asynchronously modifies a row atomically on the server. The method
   * reads the latest existing timestamp and value from the specified columns and writes a new
   * entry. The new value for the timestamp is the greater of the existing timestamp or the current
   * server time. The method returns the new contents of all modified cells.
   *
   * <p>Sample code:
   *
   * <pre>{@code
   * try (BigtableDataClient bigtableDataClient = BigtableDataClient.create("[PROJECT]", "[INSTANCE]")) {
   *   ReadModifyWriteRow mutation = ReadModifyWriteRow.create("[TABLE]", "[KEY]")
   *     .increment("[FAMILY]", "[QUALIFIER]", 1)
   *     .append("[FAMILY2]", "[QUALIFIER2]", "suffix");
   *
   *   ApiFuture<Row> rowFuture = bigtableDataClient.readModifyWriteRowAsync(mutation);
   *
   *   ApiFutures.addCallback(rowFuture, new ApiFutureCallback<Row>() {
   *     public void onFailure(Throwable t) {
   *       if (t instanceof NotFoundException) {
   *         System.out.println("Tried to mutate a non-existent table");
   *       } else {
   *         t.printStackTrace();
   *       }
   *     }
   *     public void onSuccess(Row resultingRow) {
   *       System.out.println("Resulting row: " + resultingRow);
   *     }
   *   }, MoreExecutors.directExecutor());
   * }
   * }</pre>
   */
  public ApiFuture<Row> readModifyWriteRowAsync(ReadModifyWriteRow mutation) {
    return readModifyWriteRowCallable().futureCall(mutation);
  }

  /**
   * Modifies a row atomically on the server. The method reads the latest existing timestamp and
   * value from the specified columns and writes a new entry. The new value for the timestamp is the
   * greater of the existing timestamp or the current server time. The method returns the new
   * contents of all modified cells.
   *
   * <p>Sample code:
   *
   * <pre>{@code
   * try (BigtableDataClient bigtableDataClient = BigtableDataClient.create("[PROJECT]", "[INSTANCE]")) {
   *   ReadModifyWriteRow mutation = ReadModifyWriteRow.create("[TABLE]", "[KEY]")
   *     .increment("[FAMILY]", "[QUALIFIER]", 1)
   *     .append("[FAMILY2]", "[QUALIFIER2]", "suffix");
   *
   *   try {
   *     Row row = bigtableDataClient.readModifyWriteRowCallable().call(mutation);
   *   } catch (NotFoundException e) {
   *     System.out.println("Tried to mutate a non-existent table");
   *   } catch (RuntimeException e) {
   *     e.printStackTrace();
   *   }
   * }
   * }</pre>
   */
  public UnaryCallable<ReadModifyWriteRow, Row> readModifyWriteRowCallable() {
    return stub.readModifyWriteRowCallable();
  }

  /** Close the clients and releases all associated resources. */
  @Override
  public void close() {
    stub.close();
  }
}
