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# Java Native API

## 1. Function Introduction

IoTDB provides a Java native client driver and a session pool management mechanism. These tools enable developers to interact with IoTDB using object-oriented APIs, allowing time-series objects to be directly assembled and inserted into the database without constructing SQL statements. It is recommended to use the  `ITableSessionPool` for multi-threaded database operations to maximize efficiency.

## 2. Usage Instructions

**Environment Requirements**

- **JDK**: Version 1.8 or higher
- **Maven**: Version 3.6 or higher

**Adding Maven Dependencies**

```XML
<dependencies>
    <dependency>
      <groupId>org.apache.iotdb</groupId>
      <artifactId>iotdb-session</artifactId>
      <version>2.0.1-beta</version>
    </dependency>
</dependencies>
```

## 3. Read and Write Operations

### 3.1 ITableSession Interface

#### 3.1.1 Feature Description

The `ITableSession` interface defines basic operations for interacting with IoTDB, including data insertion, query execution, and session closure. Note that this interface is **not thread-safe**.

#### 3.1.2 Method Overview

| **Method Name**                                     | **Description**                                              | **Parameters**                                               | **Return Value** | **Exceptions**                                            |
| --------------------------------------------------- | ------------------------------------------------------------ | ------------------------------------------------------------ | ---------------- | --------------------------------------------------------- |
| insert(Tablet tablet)                               | Inserts a `Tablet` containing time-series data into the database. | `tablet`: The `Tablet` object to be inserted.                | None             | `StatementExecutionException`, `IoTDBConnectionException` |
| executeNonQueryStatement(String sql)                | Executes non-query SQL statements such as DDL or DML commands. | `sql`: The SQL statement to execute.                         | None             | `StatementExecutionException`, `IoTDBConnectionException` |
| executeQueryStatement(String sql)                   | Executes a query SQL statement and returns a `SessionDataSet` containing the query results. | `sql`: The SQL query statement to execute.                   | `SessionDataSet` | `StatementExecutionException`, `IoTDBConnectionException` |
| executeQueryStatement(String sql, long timeoutInMs) | Executes a query SQL statement with a specified timeout in milliseconds. | `sql`: The SQL query statement. `timeoutInMs`: Query timeout in milliseconds. | `SessionDataSet` | `StatementExecutionException`                             |
| close()                                             | Closes the session and releases resources.                   | None                                                         | None             | IoTDBConnectionException                                  |

#### 3.1.3 Sample Code

```Java
/**
 * This interface defines a session for interacting with IoTDB tables.
 * It supports operations such as data insertion, executing queries, and closing the session.
 * Implementations of this interface are expected to manage connections and ensure
 * proper resource cleanup.
 *
 * <p>Each method may throw exceptions to indicate issues such as connection errors or
 * execution failures.
 *
 * <p>Since this interface extends {@link AutoCloseable}, it is recommended to use
 * try-with-resources to ensure the session is properly closed.
 */
public interface ITableSession extends AutoCloseable {

  /**
   * Inserts a {@link Tablet} into the database.
   *
   * @param tablet the tablet containing time-series data to be inserted.
   * @throws StatementExecutionException if an error occurs while executing the statement.
   * @throws IoTDBConnectionException    if there is an issue with the IoTDB connection.
   */
  void insert(Tablet tablet) throws StatementExecutionException, IoTDBConnectionException;

  /**
   * Executes a non-query SQL statement, such as a DDL or DML command.
   *
   * @param sql the SQL statement to execute.
   * @throws IoTDBConnectionException    if there is an issue with the IoTDB connection.
   * @throws StatementExecutionException if an error occurs while executing the statement.
   */
  void executeNonQueryStatement(String sql) throws IoTDBConnectionException, StatementExecutionException;

  /**
   * Executes a query SQL statement and returns the result set.
   *
   * @param sql the SQL query statement to execute.
   * @return a {@link SessionDataSet} containing the query results.
   * @throws StatementExecutionException if an error occurs while executing the statement.
   * @throws IoTDBConnectionException    if there is an issue with the IoTDB connection.
   */
  SessionDataSet executeQueryStatement(String sql)
      throws StatementExecutionException, IoTDBConnectionException;

  /**
   * Executes a query SQL statement with a specified timeout and returns the result set.
   *
   * @param sql         the SQL query statement to execute.
   * @param timeoutInMs the timeout duration in milliseconds for the query execution.
   * @return a {@link SessionDataSet} containing the query results.
   * @throws StatementExecutionException if an error occurs while executing the statement.
   * @throws IoTDBConnectionException    if there is an issue with the IoTDB connection.
   */
  SessionDataSet executeQueryStatement(String sql, long timeoutInMs)
      throws StatementExecutionException, IoTDBConnectionException;

  /**
   * Closes the session, releasing any held resources.
   *
   * @throws IoTDBConnectionException if there is an issue with closing the IoTDB connection.
   */
  @Override
  void close() throws IoTDBConnectionException;
}
```

### 3.2 TableSessionBuilder Class

#### 3.2.1 Feature Description

The `TableSessionBuilder` class is a builder for configuring and creating instances of the `ITableSession` interface. It allows developers to set connection parameters, query parameters, and security features.

#### 3.2.2 Parameter Configuration

| **Parameter**                                       | **Description**                                              | **Default Value**                                 |
|-----------------------------------------------------| ------------------------------------------------------------ | ------------------------------------------------- |
| nodeUrls(List\<String> nodeUrls)                    | Sets the list of IoTDB cluster node URLs.                    | `Collections.singletonList("``localhost:6667``")` |
| username(String username)                           | Sets the username for the connection.                        | `"root"`                                          |
| password(String password)                           | Sets the password for the connection.                        | `"root"`                                          |
| database(String database)                           | Sets the target database name.                               | `null`                                            |
| queryTimeoutInMs(long queryTimeoutInMs)             | Sets the query timeout in milliseconds.                      | `60000` (1 minute)                                |
| fetchSize(int fetchSize)                            | Sets the fetch size for query results.                       | `5000`                                            |
| zoneId(ZoneId zoneId)                               | Sets the timezone-related `ZoneId`.                          | `ZoneId.systemDefault()`                          |
| thriftDefaultBufferSize(int thriftDefaultBufferSize) | Sets the default buffer size for the Thrift client (in bytes). | `1024`(1KB)                                       |
| thriftMaxFrameSize(int thriftMaxFrameSize)          | Sets the maximum frame size for the Thrift client (in bytes). | `64 * 1024 * 1024`(64MB)                          |
| enableRedirection(boolean enableRedirection)        | Enables or disables redirection for cluster nodes.           | `true`                                            |
| enableAutoFetch(boolean enableAutoFetch)            | Enables or disables automatic fetching of available DataNodes. | `true`                                            |
| maxRetryCount(int maxRetryCount)                    | Sets the maximum number of connection retry attempts.        | `60`                                              |
| retryIntervalInMs(long retryIntervalInMs)           | Sets the interval between retry attempts (in milliseconds).  | `500`(500 millisesonds)                           |
| useSSL(boolean useSSL)                              | Enables or disables SSL for secure connections.              | `false`                                           |
| trustStore(String keyStore)                         | Sets the path to the trust store for SSL connections.        | `null`                                            |
| trustStorePwd(String keyStorePwd)                   | Sets the password for the SSL trust store.                   | `null`                                            |
| enableCompression(boolean enableCompression)        | Enables or disables RPC compression for the connection.      | `false`                                           |
| connectionTimeoutInMs(int connectionTimeoutInMs)    | Sets the connection timeout in milliseconds.                 | `0` (no timeout)                                  |

#### 3.2.3 Sample Code

```Java
/**
 * A builder class for constructing instances of {@link ITableSession}.
 *
 * <p>This builder provides a fluent API for configuring various options such as connection 
 * settings, query parameters, and security features.
 *
 * <p>All configurations have reasonable default values, which can be overridden as needed.
 */
public class TableSessionBuilder {

    /**
     * Builds and returns a configured {@link ITableSession} instance.
     *
     * @return a fully configured {@link ITableSession}.
     * @throws IoTDBConnectionException if an error occurs while establishing the connection.
     */
    public ITableSession build() throws IoTDBConnectionException;

    /**
     * Sets the list of node URLs for the IoTDB cluster.
     *
     * @param nodeUrls a list of node URLs.
     * @return the current {@link TableSessionBuilder} instance.
     * @defaultValue Collection.singletonList("localhost:6667")
     */
    public TableSessionBuilder nodeUrls(List<String> nodeUrls);

    /**
     * Sets the username for the connection.
     *
     * @param username the username.
     * @return the current {@link TableSessionBuilder} instance.
     * @defaultValue "root"
     */
    public TableSessionBuilder username(String username);

    /**
     * Sets the password for the connection.
     *
     * @param password the password.
     * @return the current {@link TableSessionBuilder} instance.
     * @defaultValue "root"
     */
    public TableSessionBuilder password(String password);

    /**
     * Sets the target database name.
     *
     * @param database the database name.
     * @return the current {@link TableSessionBuilder} instance.
     * @defaultValue null
     */
    public TableSessionBuilder database(String database);

    /**
     * Sets the query timeout in milliseconds.
     *
     * @param queryTimeoutInMs the query timeout in milliseconds.
     * @return the current {@link TableSessionBuilder} instance.
     * @defaultValue 60000 (1 minute)
     */
    public TableSessionBuilder queryTimeoutInMs(long queryTimeoutInMs);

    /**
     * Sets the fetch size for query results.
     *
     * @param fetchSize the fetch size.
     * @return the current {@link TableSessionBuilder} instance.
     * @defaultValue 5000
     */
    public TableSessionBuilder fetchSize(int fetchSize);

    /**
     * Sets the {@link ZoneId} for timezone-related operations.
     *
     * @param zoneId the {@link ZoneId}.
     * @return the current {@link TableSessionBuilder} instance.
     * @defaultValue ZoneId.systemDefault()
     */
    public TableSessionBuilder zoneId(ZoneId zoneId);

    /**
     * Sets the default init buffer size for the Thrift client.
     *
     * @param thriftDefaultBufferSize the buffer size in bytes.
     * @return the current {@link TableSessionBuilder} instance.
     * @defaultValue 1024 (1 KB)
     */
    public TableSessionBuilder thriftDefaultBufferSize(int thriftDefaultBufferSize);

    /**
     * Sets the maximum frame size for the Thrift client.
     *
     * @param thriftMaxFrameSize the maximum frame size in bytes.
     * @return the current {@link TableSessionBuilder} instance.
     * @defaultValue 64 * 1024 * 1024 (64 MB)
     */
    public TableSessionBuilder thriftMaxFrameSize(int thriftMaxFrameSize);

    /**
     * Enables or disables redirection for cluster nodes.
     *
     * @param enableRedirection whether to enable redirection.
     * @return the current {@link TableSessionBuilder} instance.
     * @defaultValue true
     */
    public TableSessionBuilder enableRedirection(boolean enableRedirection);

    /**
     * Enables or disables automatic fetching of available DataNodes.
     *
     * @param enableAutoFetch whether to enable automatic fetching.
     * @return the current {@link TableSessionBuilder} instance.
     * @defaultValue true
     */
    public TableSessionBuilder enableAutoFetch(boolean enableAutoFetch);

    /**
     * Sets the maximum number of retries for connection attempts.
     *
     * @param maxRetryCount the maximum retry count.
     * @return the current {@link TableSessionBuilder} instance.
     * @defaultValue 60
     */
    public TableSessionBuilder maxRetryCount(int maxRetryCount);

    /**
     * Sets the interval between retries in milliseconds.
     *
     * @param retryIntervalInMs the interval in milliseconds.
     * @return the current {@link TableSessionBuilder} instance.
     * @defaultValue 500 milliseconds
     */
    public TableSessionBuilder retryIntervalInMs(long retryIntervalInMs);

    /**
     * Enables or disables SSL for secure connections.
     *
     * @param useSSL whether to enable SSL.
     * @return the current {@link TableSessionBuilder} instance.
     * @defaultValue false
     */
    public TableSessionBuilder useSSL(boolean useSSL);

    /**
     * Sets the trust store path for SSL connections.
     *
     * @param keyStore the trust store path.
     * @return the current {@link TableSessionBuilder} instance.
     * @defaultValue null
     */
    public TableSessionBuilder trustStore(String keyStore);

    /**
     * Sets the trust store password for SSL connections.
     *
     * @param keyStorePwd the trust store password.
     * @return the current {@link TableSessionBuilder} instance.
     * @defaultValue null
     */
    public TableSessionBuilder trustStorePwd(String keyStorePwd);

    /**
     * Enables or disables rpc compression for the connection.
     *
     * @param enableCompression whether to enable compression.
     * @return the current {@link TableSessionBuilder} instance.
     * @defaultValue false
     */
    public TableSessionBuilder enableCompression(boolean enableCompression);

    /**
     * Sets the connection timeout in milliseconds.
     *
     * @param connectionTimeoutInMs the connection timeout in milliseconds.
     * @return the current {@link TableSessionBuilder} instance.
     * @defaultValue 0 (no timeout)
     */
    public TableSessionBuilder connectionTimeoutInMs(int connectionTimeoutInMs);
}
```

## 4. Session Pool

### 4.1 ITableSessionPool Interface

#### 4.1.1 Feature Description

The `ITableSessionPool` interface manages a pool of `ITableSession` instances, enabling efficient reuse of connections and proper cleanup of resources.

#### 4.1.2 Method Overview

| **Method Name** | **Description**                                            | **Return Value** | **Exceptions**             |
| --------------- | ---------------------------------------------------------- | ---------------- | -------------------------- |
| getSession()    | Acquires a session from the pool for database interaction. | `ITableSession`  | `IoTDBConnectionException` |
| close()         | Closes the session pool and releases resources.。          | None             | None                       |

#### 4.1.3 Sample Code

```Java
/**
 * This interface defines a pool for managing {@link ITableSession} instances.
 * It provides methods to acquire a session from the pool and to close the pool.
 *
 * <p>The implementation should handle the lifecycle of sessions, ensuring efficient
 * reuse and proper cleanup of resources.
 */
public interface ITableSessionPool {

    /**
     * Acquires an {@link ITableSession} instance from the pool.
     *
     * @return an {@link ITableSession} instance for interacting with the IoTDB.
     * @throws IoTDBConnectionException if there is an issue obtaining a session from the pool.
     */
    ITableSession getSession() throws IoTDBConnectionException;

    /**
     * Closes the session pool, releasing any held resources.
     *
     * <p>Once the pool is closed, no further sessions can be acquired.
     */
    void close();
}
```

### 4.2 TableSessionPoolBuilder Class

#### 4.2.1 Feature Description

The `TableSessionPoolBuilder` class is a builder for configuring and creating `ITableSessionPool` instances, supporting options like connection settings and pooling behavior.

#### 4.2.2 Parameter Configuration

| **Parameter**                                                 | **Description**                                              | **Default Value**                             |
|---------------------------------------------------------------| ------------------------------------------------------------ | --------------------------------------------- |
| nodeUrls(List\<String> nodeUrls)                              | Sets the list of IoTDB cluster node URLs.                    | `Collections.singletonList("localhost:6667")` |
| maxSize(int maxSize)                                          | Sets the maximum size of the session pool, i.e., the maximum number of sessions allowed in the pool. | `5`                                           |
| user(String user)                                             | Sets the username for the connection.                        | `"root"`                                      |
| password(String password)                                     | Sets the password for the connection.                        | `"root"`                                      |
| database(String database)                                     | Sets the target database name.                               | `"root"`                                      |
| queryTimeoutInMs(long queryTimeoutInMs)                       | Sets the query timeout in milliseconds.                      | `60000`(1 minute)                             |
| fetchSize(int fetchSize)                                      | Sets the fetch size for query results.                       | `5000`                                        |
| zoneId(ZoneId zoneId)                                         | Sets the timezone-related `ZoneId`.                          | `ZoneId.systemDefault()`                      |
| waitToGetSessionTimeoutInMs(long waitToGetSessionTimeoutInMs) | Sets the timeout duration (in milliseconds) for acquiring a session from the pool. | `30000`(30 seconds)                           |
| thriftDefaultBufferSize(int thriftDefaultBufferSize)          | Sets the default buffer size for the Thrift client (in bytes). | `1024`(1KB)                                   |
| thriftMaxFrameSize(int thriftMaxFrameSize)                    | Sets the maximum frame size for the Thrift client (in bytes). | `64 * 1024 * 1024`(64MB)                      |
| enableCompression(boolean enableCompression)                  | Enables or disables compression for the connection.          | `false`                                       |
| enableRedirection(boolean enableRedirection)                  | Enables or disables redirection for cluster nodes.           | `true`                                        |
| connectionTimeoutInMs(int connectionTimeoutInMs)              | Sets the connection timeout in milliseconds.                 | `10000` (10 seconds)                          |
| enableAutoFetch(boolean enableAutoFetch)                      | Enables or disables automatic fetching of available DataNodes. | `true`                                        |
| maxRetryCount(int maxRetryCount)                              | Sets the maximum number of connection retry attempts.        | `60`                                          |
| retryIntervalInMs(long retryIntervalInMs)                     | Sets the interval between retry attempts (in milliseconds).  | `500` (500 milliseconds)                      |
| useSSL(boolean useSSL)                                        | Enables or disables SSL for secure connections.              | `false`                                       |
| trustStore(String keyStore)                                   | Sets the path to the trust store for SSL connections.        | `null`                                        |
| trustStorePwd(String keyStorePwd)                             | Sets the password for the SSL trust store.                   | `null`                                        |

#### 4.2.3 Sample Code

```Java
/**
 * A builder class for constructing instances of {@link ITableSessionPool}.
 *
 * <p>This builder provides a fluent API for configuring a session pool, including
 * connection settings, session parameters, and pool behavior.
 *
 * <p>All configurations have reasonable default values, which can be overridden as needed.
 */
public class TableSessionPoolBuilder {

    /**
     * Builds and returns a configured {@link ITableSessionPool} instance.
     *
     * @return a fully configured {@link ITableSessionPool}.
     */
    public ITableSessionPool build();

    /**
     * Sets the list of node URLs for the IoTDB cluster.
     *
     * @param nodeUrls a list of node URLs.
     * @return the current {@link TableSessionPoolBuilder} instance.
     * @defaultValue Collection.singletonList("localhost:6667")
     */
    public TableSessionPoolBuilder nodeUrls(List<String> nodeUrls);

    /**
     * Sets the maximum size of the session pool.
     *
     * @param maxSize the maximum number of sessions allowed in the pool.
     * @return the current {@link TableSessionPoolBuilder} instance.
     * @defaultValue 5
     */
    public TableSessionPoolBuilder maxSize(int maxSize);

    /**
     * Sets the username for the connection.
     *
     * @param user the username.
     * @return the current {@link TableSessionPoolBuilder} instance.
     * @defaultValue "root"
     */
    public TableSessionPoolBuilder user(String user);

    /**
     * Sets the password for the connection.
     *
     * @param password the password.
     * @return the current {@link TableSessionPoolBuilder} instance.
     * @defaultValue "root"
     */
    public TableSessionPoolBuilder password(String password);

    /**
     * Sets the target database name.
     *
     * @param database the database name.
     * @return the current {@link TableSessionPoolBuilder} instance.
     * @defaultValue "root"
     */
    public TableSessionPoolBuilder database(String database);

    /**
     * Sets the query timeout in milliseconds.
     *
     * @param queryTimeoutInMs the query timeout in milliseconds.
     * @return the current {@link TableSessionPoolBuilder} instance.
     * @defaultValue 60000 (1 minute)
     */
    public TableSessionPoolBuilder queryTimeoutInMs(long queryTimeoutInMs);

    /**
     * Sets the fetch size for query results.
     *
     * @param fetchSize the fetch size.
     * @return the current {@link TableSessionPoolBuilder} instance.
     * @defaultValue 5000
     */
    public TableSessionPoolBuilder fetchSize(int fetchSize);

    /**
     * Sets the {@link ZoneId} for timezone-related operations.
     *
     * @param zoneId the {@link ZoneId}.
     * @return the current {@link TableSessionPoolBuilder} instance.
     * @defaultValue ZoneId.systemDefault()
     */
    public TableSessionPoolBuilder zoneId(ZoneId zoneId);

    /**
     * Sets the timeout for waiting to acquire a session from the pool.
     *
     * @param waitToGetSessionTimeoutInMs the timeout duration in milliseconds.
     * @return the current {@link TableSessionPoolBuilder} instance.
     * @defaultValue 30000 (30 seconds)
     */
    public TableSessionPoolBuilder waitToGetSessionTimeoutInMs(long waitToGetSessionTimeoutInMs);

    /**
     * Sets the default buffer size for the Thrift client.
     *
     * @param thriftDefaultBufferSize the buffer size in bytes.
     * @return the current {@link TableSessionPoolBuilder} instance.
     * @defaultValue 1024 (1 KB)
     */
    public TableSessionPoolBuilder thriftDefaultBufferSize(int thriftDefaultBufferSize);

    /**
     * Sets the maximum frame size for the Thrift client.
     *
     * @param thriftMaxFrameSize the maximum frame size in bytes.
     * @return the current {@link TableSessionPoolBuilder} instance.
     * @defaultValue 64 * 1024 * 1024 (64 MB)
     */
    public TableSessionPoolBuilder thriftMaxFrameSize(int thriftMaxFrameSize);

    /**
     * Enables or disables compression for the connection.
     *
     * @param enableCompression whether to enable compression.
     * @return the current {@link TableSessionPoolBuilder} instance.
     * @defaultValue false
     */
    public TableSessionPoolBuilder enableCompression(boolean enableCompression);

    /**
     * Enables or disables redirection for cluster nodes.
     *
     * @param enableRedirection whether to enable redirection.
     * @return the current {@link TableSessionPoolBuilder} instance.
     * @defaultValue true
     */
    public TableSessionPoolBuilder enableRedirection(boolean enableRedirection);

    /**
     * Sets the connection timeout in milliseconds.
     *
     * @param connectionTimeoutInMs the connection timeout in milliseconds.
     * @return the current {@link TableSessionPoolBuilder} instance.
     * @defaultValue 10000 (10 seconds)
     */
    public TableSessionPoolBuilder connectionTimeoutInMs(int connectionTimeoutInMs);

    /**
     * Enables or disables automatic fetching of available DataNodes.
     *
     * @param enableAutoFetch whether to enable automatic fetching.
     * @return the current {@link TableSessionPoolBuilder} instance.
     * @defaultValue true
     */
    public TableSessionPoolBuilder enableAutoFetch(boolean enableAutoFetch);

    /**
     * Sets the maximum number of retries for connection attempts.
     *
     * @param maxRetryCount the maximum retry count.
     * @return the current {@link TableSessionPoolBuilder} instance.
     * @defaultValue 60
     */
    public TableSessionPoolBuilder maxRetryCount(int maxRetryCount);

    /**
     * Sets the interval between retries in milliseconds.
     *
     * @param retryIntervalInMs the interval in milliseconds.
     * @return the current {@link TableSessionPoolBuilder} instance.
     * @defaultValue 500 milliseconds
     */
    public TableSessionPoolBuilder retryIntervalInMs(long retryIntervalInMs);

    /**
     * Enables or disables SSL for secure connections.
     *
     * @param useSSL whether to enable SSL.
     * @return the current {@link TableSessionPoolBuilder} instance.
     * @defaultValue false
     */
    public TableSessionPoolBuilder useSSL(boolean useSSL);

    /**
     * Sets the trust store path for SSL connections.
     *
     * @param keyStore the trust store path.
     * @return the current {@link TableSessionPoolBuilder} instance.
     * @defaultValue null
     */
    public TableSessionPoolBuilder trustStore(String keyStore);

    /**
     * Sets the trust store password for SSL connections.
     *
     * @param keyStorePwd the trust store password.
     * @return the current {@link TableSessionPoolBuilder} instance.
     * @defaultValue null
     */
    public TableSessionPoolBuilder trustStorePwd(String keyStorePwd);
}
```

## 5. Example Code

Session: [src/main/java/org/apache/iotdb/TableModelSessionExample.java](https://github.com/apache/iotdb/blob/rc/2.0.1/example/session/src/main/java/org/apache/iotdb/TableModelSessionExample.java)

SessionPool: [src/main/java/org/apache/iotdb/TableModelSessionPoolExample.java](https://github.com/apache/iotdb/blob/rc/2.0.1/example/session/src/main/java/org/apache/iotdb/TableModelSessionPoolExample.java)

```Java
/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you 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
 *
 *     http://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 org.apache.iotdb;

import org.apache.iotdb.isession.ITableSession;
import org.apache.iotdb.isession.SessionDataSet;
import org.apache.iotdb.isession.pool.ITableSessionPool;
import org.apache.iotdb.rpc.IoTDBConnectionException;
import org.apache.iotdb.rpc.StatementExecutionException;
import org.apache.iotdb.session.pool.TableSessionPoolBuilder;

import org.apache.tsfile.enums.TSDataType;
import org.apache.tsfile.write.record.Tablet;
import org.apache.tsfile.write.record.Tablet.ColumnCategory;
import org.apache.tsfile.write.schema.IMeasurementSchema;
import org.apache.tsfile.write.schema.MeasurementSchema;

import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collections;
import java.util.List;

public class TableModelSessionPoolExample {

  private static final String LOCAL_URL = "127.0.0.1:6667";

  public static void main(String[] args) {

    // don't specify database in constructor
    ITableSessionPool tableSessionPool =
        new TableSessionPoolBuilder()
            .nodeUrls(Collections.singletonList(LOCAL_URL))
            .user("root")
            .password("root")
            .maxSize(1)
            .build();

    try (ITableSession session = tableSessionPool.getSession()) {

      session.executeNonQueryStatement("CREATE DATABASE test1");
      session.executeNonQueryStatement("CREATE DATABASE test2");

      session.executeNonQueryStatement("use test2");

      // or use full qualified table name
      session.executeNonQueryStatement(
          "create table test1.table1("
              + "region_id STRING TAG, "
              + "plant_id STRING TAG, "
              + "device_id STRING TAG, "
              + "model STRING ATTRIBUTE, "
              + "temperature FLOAT FIELD, "
              + "humidity DOUBLE FIELD) with (TTL=3600000)");

      session.executeNonQueryStatement(
          "create table table2("
              + "region_id STRING TAG, "
              + "plant_id STRING TAG, "
              + "color STRING ATTRIBUTE, "
              + "temperature FLOAT FIELD, "
              + "speed DOUBLE FIELD) with (TTL=6600000)");

      // show tables from current database
      try (SessionDataSet dataSet = session.executeQueryStatement("SHOW TABLES")) {
        System.out.println(dataSet.getColumnNames());
        System.out.println(dataSet.getColumnTypes());
        while (dataSet.hasNext()) {
          System.out.println(dataSet.next());
        }
      }

      // show tables by specifying another database
      // using SHOW tables FROM
      try (SessionDataSet dataSet = session.executeQueryStatement("SHOW TABLES FROM test1")) {
        System.out.println(dataSet.getColumnNames());
        System.out.println(dataSet.getColumnTypes());
        while (dataSet.hasNext()) {
          System.out.println(dataSet.next());
        }
      }

      // insert table data by tablet
      List<IMeasurementSchema> measurementSchemaList =
          new ArrayList<>(
              Arrays.asList(
                  new MeasurementSchema("region_id", TSDataType.STRING),
                  new MeasurementSchema("plant_id", TSDataType.STRING),
                  new MeasurementSchema("device_id", TSDataType.STRING),
                  new MeasurementSchema("model", TSDataType.STRING),
                  new MeasurementSchema("temperature", TSDataType.FLOAT),
                  new MeasurementSchema("humidity", TSDataType.DOUBLE)));
      List<ColumnCategory> columnTypeList =
          new ArrayList<>(
              Arrays.asList(
                  ColumnCategory.TAG,
                  ColumnCategory.TAG,
                  ColumnCategory.TAG,
                  ColumnCategory.ATTRIBUTE,
                  ColumnCategory.FIELD,
                  ColumnCategory.FIELD));
      Tablet tablet =
          new Tablet(
              "test1",
              IMeasurementSchema.getMeasurementNameList(measurementSchemaList),
              IMeasurementSchema.getDataTypeList(measurementSchemaList),
              columnTypeList,
              100);
      for (long timestamp = 0; timestamp < 100; timestamp++) {
        int rowIndex = tablet.getRowSize();
        tablet.addTimestamp(rowIndex, timestamp);
        tablet.addValue("region_id", rowIndex, "1");
        tablet.addValue("plant_id", rowIndex, "5");
        tablet.addValue("device_id", rowIndex, "3");
        tablet.addValue("model", rowIndex, "A");
        tablet.addValue("temperature", rowIndex, 37.6F);
        tablet.addValue("humidity", rowIndex, 111.1);
        if (tablet.getRowSize() == tablet.getMaxRowNumber()) {
          session.insert(tablet);
          tablet.reset();
        }
      }
      if (tablet.getRowSize() != 0) {
        session.insert(tablet);
        tablet.reset();
      }

      // query table data
      try (SessionDataSet dataSet =
          session.executeQueryStatement(
              "select * from test1 "
                  + "where region_id = '1' and plant_id in ('3', '5') and device_id = '3'")) {
        System.out.println(dataSet.getColumnNames());
        System.out.println(dataSet.getColumnTypes());
        while (dataSet.hasNext()) {
          System.out.println(dataSet.next());
        }
      }

    } catch (IoTDBConnectionException e) {
      e.printStackTrace();
    } catch (StatementExecutionException e) {
      e.printStackTrace();
    } finally {
      tableSessionPool.close();
    }

    // specify database in constructor
    tableSessionPool =
        new TableSessionPoolBuilder()
            .nodeUrls(Collections.singletonList(LOCAL_URL))
            .user("root")
            .password("root")
            .maxSize(1)
            .database("test1")
            .build();

    try (ITableSession session = tableSessionPool.getSession()) {

      // show tables from current database
      try (SessionDataSet dataSet = session.executeQueryStatement("SHOW TABLES")) {
        System.out.println(dataSet.getColumnNames());
        System.out.println(dataSet.getColumnTypes());
        while (dataSet.hasNext()) {
          System.out.println(dataSet.next());
        }
      }

      // change database to test2
      session.executeNonQueryStatement("use test2");

      // show tables by specifying another database
      // using SHOW tables FROM
      try (SessionDataSet dataSet = session.executeQueryStatement("SHOW TABLES")) {
        System.out.println(dataSet.getColumnNames());
        System.out.println(dataSet.getColumnTypes());
        while (dataSet.hasNext()) {
          System.out.println(dataSet.next());
        }
      }

    } catch (IoTDBConnectionException e) {
      e.printStackTrace();
    } catch (StatementExecutionException e) {
      e.printStackTrace();
    }

    try (ITableSession session = tableSessionPool.getSession()) {

      // show tables from default database test1
      try (SessionDataSet dataSet = session.executeQueryStatement("SHOW TABLES")) {
        System.out.println(dataSet.getColumnNames());
        System.out.println(dataSet.getColumnTypes());
        while (dataSet.hasNext()) {
          System.out.println(dataSet.next());
        }
      }

    } catch (IoTDBConnectionException e) {
      e.printStackTrace();
    } catch (StatementExecutionException e) {
      e.printStackTrace();
    } finally {
      tableSessionPool.close();
    }
  }
}
```