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docs: jdbc add seek doc

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docs/en/14-reference/03-connector/04-java.mdx
浏览文件 @ 2641dfa0
...@@ -32,25 +32,22 @@ TDengine's JDBC driver implementation is as consistent as possible with the rela ...@@ -32,25 +32,22 @@ TDengine's JDBC driver implementation is as consistent as possible with the rela
Native connections are supported on the same platforms as the TDengine client driver. Native connections are supported on the same platforms as the TDengine client driver.
REST connection supports all platforms that can run Java. REST connection supports all platforms that can run Java.
## Version support
Please refer to [version support list](/reference/connector#version-support)
## Recent update logs ## Recent update logs
| taos-jdbcdriver version | major changes | | taos-jdbcdriver version | major changes | TDengine Minimum version |
| :---------------------: | :------------------------------------------------------------------------------------------------------------------------------------------------: | | :---------------------: | :------------------------------------------------------------------------------------------------------------------------------------------------: | :----------------------: |
| 3.2.1 | JDBC REST connection supports schemaless/prepareStatement over WebSocket | | 3.2.1 | subscription add seek function | 3.0.5.0 |
| 3.2.0 | This version has been deprecated | | 3.2.1 | JDBC REST connection supports schemaless/prepareStatement over WebSocket | 3.0.3.0 |
| 3.1.0 | JDBC REST connection supports subscription over WebSocket | | 3.2.0 | This version has been deprecated | - |
| 3.0.1 - 3.0.4 | fix the resultSet data is parsed incorrectly sometimes. 3.0.1 is compiled on JDK 11, you are advised to use other version in the JDK 8 environment | | 3.1.0 | JDBC REST connection supports subscription over WebSocket | - |
| 3.0.0 | Support for TDengine 3.0 | | 3.0.1 - 3.0.4 | fix the resultSet data is parsed incorrectly sometimes. 3.0.1 is compiled on JDK 11, you are advised to use other version in the JDK 8 environment | - |
| 2.0.42 | fix wasNull interface return value in WebSocket connection | | 3.0.0 | Support for TDengine 3.0 | 3.0.0.0 |
| 2.0.41 | fix decode method of username and password in REST connection | | 2.0.42 | fix wasNull interface return value in WebSocket connection | - |
| 2.0.39 - 2.0.40 | Add REST connection/request timeout parameters | | 2.0.41 | fix decode method of username and password in REST connection | - |
| 2.0.38 | JDBC REST connections add bulk pull function | | 2.0.39 - 2.0.40 | Add REST connection/request timeout parameters | - |
| 2.0.37 | Support json tags | | 2.0.38 | JDBC REST connections add bulk pull function | - |
| 2.0.36 | Support schemaless writing | | 2.0.37 | Support json tags | - |
| 2.0.36 | Support schemaless writing | - |
**Note**: adding `batchfetch` to the REST connection and setting it to true will enable the WebSocket connection. **Note**: adding `batchfetch` to the REST connection and setting it to true will enable the WebSocket connection.
...@@ -102,6 +99,8 @@ For specific error codes, please refer to. ...@@ -102,6 +99,8 @@ For specific error codes, please refer to.
| 0x2319 | user is required | The user name information is missing when creating the connection | | 0x2319 | user is required | The user name information is missing when creating the connection |
| 0x231a | password is required | Password information is missing when creating a connection | | 0x231a | password is required | Password information is missing when creating a connection |
| 0x231c | httpEntity is null, sql: | Execution exception occurred during the REST connection | | 0x231c | httpEntity is null, sql: | Execution exception occurred during the REST connection |
| 0x231d | can't create connection with server within | Increase the connection time by adding the httpConnectTimeout parameter, or check the connection to the taos adapter. |
| 0x231e | failed to complete the task within the specified time | Increase the execution time by adding the messageWaitTimeout parameter, or check the connection to the taos adapter. |
| 0x2350 | unknown error | Unknown exception, please return to the developer on github. | | 0x2350 | unknown error | Unknown exception, please return to the developer on github. |
| 0x2352 | Unsupported encoding | An unsupported character encoding set is specified under the native Connection. | | 0x2352 | Unsupported encoding | An unsupported character encoding set is specified under the native Connection. |
| 0x2353 | internal error of database, please see taoslog for more details | An error occurs when the prepare statement is executed on the native connection. Check the taos log to locate the fault. | | 0x2353 | internal error of database, please see taoslog for more details | An error occurs when the prepare statement is executed on the native connection. Check the taos log to locate the fault. |
...@@ -117,8 +116,8 @@ For specific error codes, please refer to. ...@@ -117,8 +116,8 @@ For specific error codes, please refer to.
| 0x2376 | failed to set consumer topic, topic name is empty | During data subscription creation, the subscription topic name is empty. Check that the specified topic name is correct. | | 0x2376 | failed to set consumer topic, topic name is empty | During data subscription creation, the subscription topic name is empty. Check that the specified topic name is correct. |
| 0x2377 | consumer reference has been destroyed | The subscription data transfer channel has been closed. Please check the connection to TDengine. | | 0x2377 | consumer reference has been destroyed | The subscription data transfer channel has been closed. Please check the connection to TDengine. |
| 0x2378 | consumer create error | Failed to create a data subscription. Check the taos log according to the error message to locate the fault. | | 0x2378 | consumer create error | Failed to create a data subscription. Check the taos log according to the error message to locate the fault. |
| - | can't create connection with server within | Increase the connection time by adding the httpConnectTimeout parameter, or check the connection to the taos adapter. | | 0x2379 | seek offset must not be a negative number | The seek interface parameter cannot be negative. Use the correct parameter |
| - | failed to complete the task within the specified time | Increase the execution time by adding the messageWaitTimeout parameter, or check the connection to the taos adapter. | | 0x237a | vGroup not found in result set | subscription is not bound to the VGroup due to the rebalance mechanism |
- [TDengine Java Connector](https://github.com/taosdata/taos-connector-jdbc/blob/main/src/main/java/com/taosdata/jdbc/TSDBErrorNumbers.java) - [TDengine Java Connector](https://github.com/taosdata/taos-connector-jdbc/blob/main/src/main/java/com/taosdata/jdbc/TSDBErrorNumbers.java)
<!-- - [TDengine_ERROR_CODE](../error-code) --> <!-- - [TDengine_ERROR_CODE](../error-code) -->
...@@ -169,7 +168,7 @@ Add following dependency in the `pom.xml` file of your Maven project: ...@@ -169,7 +168,7 @@ Add following dependency in the `pom.xml` file of your Maven project:
<dependency> <dependency>
<groupId>com.taosdata.jdbc</groupId> <groupId>com.taosdata.jdbc</groupId>
<artifactId>taos-jdbcdriver</artifactId> <artifactId>taos-jdbcdriver</artifactId>
<version>3.2.1</version> <version>3.2.2</version>
</dependency> </dependency>
``` ```
...@@ -913,14 +912,15 @@ public class SchemalessWsTest { ...@@ -913,14 +912,15 @@ public class SchemalessWsTest {
public static void main(String[] args) throws SQLException { public static void main(String[] args) throws SQLException {
final String url = "jdbc:TAOS-RS://" + host + ":6041/?user=root&password=taosdata&batchfetch=true"; final String url = "jdbc:TAOS-RS://" + host + ":6041/?user=root&password=taosdata&batchfetch=true";
Connection connection = DriverManager.getConnection(url); try(Connection connection = DriverManager.getConnection(url)){
init(connection); init(connection);
SchemalessWriter writer = new SchemalessWriter(connection, "test_ws_schemaless"); try(SchemalessWriter writer = new SchemalessWriter(connection, "test_ws_schemaless")){
writer.write(lineDemo, SchemalessProtocolType.LINE, SchemalessTimestampType.NANO_SECONDS); writer.write(lineDemo, SchemalessProtocolType.LINE, SchemalessTimestampType.NANO_SECONDS);
writer.write(telnetDemo, SchemalessProtocolType.TELNET, SchemalessTimestampType.MILLI_SECONDS); writer.write(telnetDemo, SchemalessProtocolType.TELNET, SchemalessTimestampType.MILLI_SECONDS);
writer.write(jsonDemo, SchemalessProtocolType.JSON, SchemalessTimestampType.SECONDS); writer.write(jsonDemo, SchemalessProtocolType.JSON, SchemalessTimestampType.SECONDS);
System.exit(0); }
}
} }
private static void init(Connection connection) throws SQLException { private static void init(Connection connection) throws SQLException {
...@@ -991,6 +991,17 @@ while(true) { ...@@ -991,6 +991,17 @@ while(true) {
`poll` obtains one message each time it is run. `poll` obtains one message each time it is run.
#### Assignment subscription Offset
```
long position(TopicPartition partition) throws SQLException;
Map<TopicPartition, Long> position(String topic) throws SQLException;
Map<TopicPartition, Long> beginningOffsets(String topic) throws SQLException;
Map<TopicPartition, Long> endOffsets(String topic) throws SQLException;
void seek(TopicPartition partition, long offset) throws SQLException;
```
#### Close subscriptions #### Close subscriptions
```java ```java
......
docs/zh/08-connector/14-java.mdx
浏览文件 @ 2641dfa0
...@@ -32,25 +32,22 @@ TDengine 的 JDBC 驱动实现尽可能与关系型数据库驱动保持一致 ...@@ -32,25 +32,22 @@ TDengine 的 JDBC 驱动实现尽可能与关系型数据库驱动保持一致
原生连接支持的平台和 TDengine 客户端驱动支持的平台一致。 原生连接支持的平台和 TDengine 客户端驱动支持的平台一致。
REST 连接支持所有能运行 Java 的平台。 REST 连接支持所有能运行 Java 的平台。
## 版本支持 ## 版本历史
请参考[版本支持列表](../#版本支持) | taos-jdbcdriver 版本 | 主要变化 | TDengine 最低版本 |
| :------------------: | :----------------------------------------------------------------------------------------------------------------------------------------------------: | :---------------: |
## 最近更新记录 | 3.2.2 | 新增功能：数据订阅支持 seek 功能。 | 3.0.5.0 |
| 3.2.1 | 新增功能：WebSocket 连接支持 schemaless 与 prepareStatement 写入。变更：consumer poll 返回结果集为 ConsumerRecord，可通过 value() 获取指定结果集数据。 | 3.0.3.0 |
| taos-jdbcdriver 版本 | 主要变化 | | 3.2.0 | 存在连接问题，不推荐使用 | - |
| :------------------: | :----------------------------------------------------------------------------------------------------------------------------------------------------: | | 3.1.0 | WebSocket 连接支持订阅功能 | - |
| 3.2.1 | 新增功能：WebSocket 连接支持 schemaless 与 prepareStatement 写入。变更：consumer poll 返回结果集为 ConsumerRecord，可通过 value() 获取指定结果集数据。 | | 3.0.1 - 3.0.4 | 修复一些情况下结果集数据解析错误的问题。3.0.1 在 JDK 11 环境编译，JDK 8 环境下建议使用其他版本 | - |
| 3.2.0 | 存在连接问题，不推荐使用 | | 3.0.0 | 支持 TDengine 3.0 | 3.0.0.0 |
| 3.1.0 | WebSocket 连接支持订阅功能 | | 2.0.42 | 修在 WebSocket 连接中 wasNull 接口返回值 | - |
| 3.0.1 - 3.0.4 | 修复一些情况下结果集数据解析错误的问题。3.0.1 在 JDK 11 环境编译，JDK 8 环境下建议使用其他版本 | | 2.0.41 | 修正 REST 连接中用户名和密码转码方式 | - |
| 3.0.0 | 支持 TDengine 3.0 | | 2.0.39 - 2.0.40 | 增加 REST 连接/请求 超时设置 | - |
| 2.0.42 | 修在 WebSocket 连接中 wasNull 接口返回值 | | 2.0.38 | JDBC REST 连接增加批量拉取功能 | - |
| 2.0.41 | 修正 REST 连接中用户名和密码转码方式 | | 2.0.37 | 增加对 json tag 支持 | - |
| 2.0.39 - 2.0.40 | 增加 REST 连接/请求 超时设置 | | 2.0.36 | 增加对 schemaless 写入支持 | - |
| 2.0.38 | JDBC REST 连接增加批量拉取功能 |
| 2.0.37 | 增加对 json tag 支持 |
| 2.0.36 | 增加对 schemaless 写入支持 |
**注**：REST 连接中增加 `batchfetch` 参数并设置为 true，将开启 WebSocket 连接。 **注**：REST 连接中增加 `batchfetch` 参数并设置为 true，将开启 WebSocket 连接。
...@@ -80,45 +77,47 @@ JDBC 连接器可能报错的错误码包括 4 种： ...@@ -80,45 +77,47 @@ JDBC 连接器可能报错的错误码包括 4 种：
具体的错误码请参考： 具体的错误码请参考：
| Error Code | Description | Suggested Actions | | Error Code | Description | Suggested Actions |
| ---------- | --------------------------------------------------------------- | --------------------------------------------------------------------------------------- | | ---------- | --------------------------------------------------------------- | ----------------------------------------------------------------------------------------- |
| 0x2301 | connection already closed | 连接已经关闭，检查连接情况，或重新创建连接去执行相关指令。 | | 0x2301 | connection already closed | 连接已经关闭，检查连接情况，或重新创建连接去执行相关指令。 |
| 0x2302 | this operation is NOT supported currently! | 当前使用接口不支持，可以更换其他连接方式。 | | 0x2302 | this operation is NOT supported currently! | 当前使用接口不支持，可以更换其他连接方式。 |
| 0x2303 | invalid variables | 参数不合法，请检查相应接口规范，调整参数类型及大小。 | | 0x2303 | invalid variables | 参数不合法，请检查相应接口规范，调整参数类型及大小。 |
| 0x2304 | statement is closed | statement 已经关闭，请检查 statement 是否关闭后再次使用，或是连接是否正常。 | | 0x2304 | statement is closed | statement 已经关闭，请检查 statement 是否关闭后再次使用，或是连接是否正常。 |
| 0x2305 | resultSet is closed | resultSet 结果集已经释放，请检查 resultSet 是否释放后再次使用。 | | 0x2305 | resultSet is closed | resultSet 结果集已经释放，请检查 resultSet 是否释放后再次使用。 |
| 0x2306 | Batch is empty! | prepareStatement 添加参数后再执行 executeBatch。 | | 0x2306 | Batch is empty! | prepareStatement 添加参数后再执行 executeBatch。 |
| 0x2307 | Can not issue data manipulation statements with executeQuery() | 更新操作应该使用 executeUpdate()，而不是 executeQuery()。 | | 0x2307 | Can not issue data manipulation statements with executeQuery() | 更新操作应该使用 executeUpdate()，而不是 executeQuery()。 |
| 0x2308 | Can not issue SELECT via executeUpdate() | 查询操作应该使用 executeQuery()，而不是 executeUpdate()。 | | 0x2308 | Can not issue SELECT via executeUpdate() | 查询操作应该使用 executeQuery()，而不是 executeUpdate()。 |
| 0x230d | parameter index out of range | 参数越界，请检查参数的合理范围。 | | 0x230d | parameter index out of range | 参数越界，请检查参数的合理范围。 |
| 0x230e | connection already closed | 连接已经关闭，请检查 Connection 是否关闭后再次使用，或是连接是否正常。 | | 0x230e | connection already closed | 连接已经关闭，请检查 Connection 是否关闭后再次使用，或是连接是否正常。 |
| 0x230f | unknown sql type in tdengine | 请检查 TDengine 支持的 Data Type 类型。 | | 0x230f | unknown sql type in tdengine | 请检查 TDengine 支持的 Data Type 类型。 |
| 0x2310 | can't register JDBC-JNI driver | 不能注册 JNI 驱动，请检查 url 是否填写正确。 | | 0x2310 | can't register JDBC-JNI driver | 不能注册 JNI 驱动，请检查 url 是否填写正确。 |
| 0x2312 | url is not set | 请检查 REST 连接 url 是否填写正确。 | | 0x2312 | url is not set | 请检查 REST 连接 url 是否填写正确。 |
| 0x2314 | numeric value out of range | 请检查获取结果集中数值类型是否使用了正确的接口。 | | 0x2314 | numeric value out of range | 请检查获取结果集中数值类型是否使用了正确的接口。 |
| 0x2315 | unknown taos type in tdengine | 在 TDengine 数据类型与 JDBC 数据类型转换时，是否指定了正确的 TDengine 数据类型。 | | 0x2315 | unknown taos type in tdengine | 在 TDengine 数据类型与 JDBC 数据类型转换时，是否指定了正确的 TDengine 数据类型。 |
| 0x2317 | | REST 连接中使用了错误的请求类型。 | | 0x2317 | | REST 连接中使用了错误的请求类型。 |
| 0x2318 | | REST 连接中出现了数据传输异常，请检查网络情况并重试。 | | 0x2318 | | REST 连接中出现了数据传输异常，请检查网络情况并重试。 |
| 0x2319 | user is required | 创建连接时缺少用户名信息 | | 0x2319 | user is required | 创建连接时缺少用户名信息 |
| 0x231a | password is required | 创建连接时缺少密码信息 | | 0x231a | password is required | 创建连接时缺少密码信息 |
| 0x231c | httpEntity is null, sql: | REST 连接中执行出现异常 | | 0x231c | httpEntity is null, sql: | REST 连接中执行出现异常 |
| 0x2350 | unknown error | 未知异常，请在 github 反馈给开发人员。 | | 0x231d | can't create connection with server within | 通过增加参数 httpConnectTimeout 增加连接耗时，或是请检查与 taosAdapter 之间的连接情况。 |
| 0x2352 | Unsupported encoding | 本地连接下指定了不支持的字符编码集 | | 0x231e | failed to complete the task within the specified time | 通过增加参数 messageWaitTimeout 增加执行耗时，或是请检查与 taosAdapter 之间的连接情况。 |
| 0x2353 | internal error of database, please see taoslog for more details | 本地连接执行 prepareStatement 时出现错误，请检查 taos log 进行问题定位。 | | 0x2350 | unknown error | 未知异常，请在 github 反馈给开发人员。 |
| 0x2354 | JNI connection is NULL | 本地连接执行命令时，Connection 已经关闭。请检查与 TDengine 的连接情况。 | | 0x2352 | Unsupported encoding | 本地连接下指定了不支持的字符编码集 |
| 0x2355 | JNI result set is NULL | 本地连接获取结果集，结果集异常，请检查连接情况，并重试。 | | 0x2353 | internal error of database, please see taoslog for more details | 本地连接执行 prepareStatement 时出现错误，请检查 taos log 进行问题定位。 |
| 0x2356 | invalid num of fields | 本地连接获取结果集的 meta 信息不匹配。 | | 0x2354 | JNI connection is NULL | 本地连接执行命令时，Connection 已经关闭。请检查与 TDengine 的连接情况。 |
| 0x2357 | empty sql string | 填写正确的 SQL 进行执行。 | | 0x2355 | JNI result set is NULL | 本地连接获取结果集，结果集异常，请检查连接情况，并重试。 |
| 0x2359 | JNI alloc memory failed, please see taoslog for more details | 本地连接分配内存错误，请检查 taos log 进行问题定位。 | | 0x2356 | invalid num of fields | 本地连接获取结果集的 meta 信息不匹配。 |
| 0x2371 | consumer properties must not be null! | 创建订阅时参数为空，请填写正确的参数。 | | 0x2357 | empty sql string | 填写正确的 SQL 进行执行。 |
| 0x2372 | configs contain empty key, failed to set consumer property | 参数 key 中包含空值，请填写正确的参数。 | | 0x2359 | JNI alloc memory failed, please see taoslog for more details | 本地连接分配内存错误，请检查 taos log 进行问题定位。 |
| 0x2373 | failed to set consumer property, | 参数 value 中包含空值，请填写正确的参数。 | | 0x2371 | consumer properties must not be null! | 创建订阅时参数为空，请填写正确的参数。 |
| 0x2375 | topic reference has been destroyed | 创建数据订阅过程中，topic 引用被释放。请检查与 TDengine 的连接情况。 | | 0x2372 | configs contain empty key, failed to set consumer property | 参数 key 中包含空值，请填写正确的参数。 |
| 0x2376 | failed to set consumer topic, topic name is empty | 创建数据订阅过程中，订阅 topic 名称为空。请检查指定的 topic 名称是否填写正确。 | | 0x2373 | failed to set consumer property, | 参数 value 中包含空值，请填写正确的参数。 |
| 0x2377 | consumer reference has been destroyed | 订阅数据传输通道已经关闭，请检查与 TDengine 的连接情况。 | | 0x2375 | topic reference has been destroyed | 创建数据订阅过程中，topic 引用被释放。请检查与 TDengine 的连接情况。 |
| 0x2378 | consumer create error | 创建数据订阅失败，请根据错误信息检查 taos log 进行问题定位。 | | 0x2376 | failed to set consumer topic, topic name is empty | 创建数据订阅过程中，订阅 topic 名称为空。请检查指定的 topic 名称是否填写正确。 |
| - | can't create connection with server within | 通过增加参数 httpConnectTimeout 增加连接耗时，或是请检查与 taosAdapter 之间的连接情况。 | | 0x2377 | consumer reference has been destroyed | 订阅数据传输通道已经关闭，请检查与 TDengine 的连接情况。 |
| - | failed to complete the task within the specified time | 通过增加参数 messageWaitTimeout 增加执行耗时，或是请检查与 taosAdapter 之间的连接情况。 | | 0x2378 | consumer create error | 创建数据订阅失败，请根据错误信息检查 taos log 进行问题定位。 |
| 0x2379 | seek offset must not be a negative number | seek 接口参数不能为负值，请使用正确的参数 |
| 0x237a | vGroup not found in result set | VGroup 没有分配给当前 consumer，由于 Rebalance 机制导致 Consumer 与 VGroup 不是绑定的关系 |
- [TDengine Java Connector](https://github.com/taosdata/taos-connector-jdbc/blob/main/src/main/java/com/taosdata/jdbc/TSDBErrorNumbers.java) - [TDengine Java Connector](https://github.com/taosdata/taos-connector-jdbc/blob/main/src/main/java/com/taosdata/jdbc/TSDBErrorNumbers.java)
<!-- - [TDengine_ERROR_CODE](../error-code) --> <!-- - [TDengine_ERROR_CODE](../error-code) -->
...@@ -169,7 +168,7 @@ Maven 项目中，在 pom.xml 中添加以下依赖： ...@@ -169,7 +168,7 @@ Maven 项目中，在 pom.xml 中添加以下依赖：
<dependency> <dependency>
<groupId>com.taosdata.jdbc</groupId> <groupId>com.taosdata.jdbc</groupId>
<artifactId>taos-jdbcdriver</artifactId> <artifactId>taos-jdbcdriver</artifactId>
<version>3.2.1</version> <version>3.2.2</version>
</dependency> </dependency>
``` ```
...@@ -916,14 +915,15 @@ public class SchemalessWsTest { ...@@ -916,14 +915,15 @@ public class SchemalessWsTest {
public static void main(String[] args) throws SQLException { public static void main(String[] args) throws SQLException {
final String url = "jdbc:TAOS-RS://" + host + ":6041/?user=root&password=taosdata&batchfetch=true"; final String url = "jdbc:TAOS-RS://" + host + ":6041/?user=root&password=taosdata&batchfetch=true";
Connection connection = DriverManager.getConnection(url); try(Connection connection = DriverManager.getConnection(url)){
init(connection); init(connection);
SchemalessWriter writer = new SchemalessWriter(connection, "test_ws_schemaless"); try(SchemalessWriter writer = new SchemalessWriter(connection, "test_ws_schemaless")){
writer.write(lineDemo, SchemalessProtocolType.LINE, SchemalessTimestampType.NANO_SECONDS); writer.write(lineDemo, SchemalessProtocolType.LINE, SchemalessTimestampType.NANO_SECONDS);
writer.write(telnetDemo, SchemalessProtocolType.TELNET, SchemalessTimestampType.MILLI_SECONDS); writer.write(telnetDemo, SchemalessProtocolType.TELNET, SchemalessTimestampType.MILLI_SECONDS);
writer.write(jsonDemo, SchemalessProtocolType.JSON, SchemalessTimestampType.SECONDS); writer.write(jsonDemo, SchemalessProtocolType.JSON, SchemalessTimestampType.SECONDS);
System.exit(0); }
}
} }
private static void init(Connection connection) throws SQLException { private static void init(Connection connection) throws SQLException {
...@@ -994,6 +994,17 @@ while(true) { ...@@ -994,6 +994,17 @@ while(true) {
`poll` 每次调用获取一个消息。 `poll` 每次调用获取一个消息。
#### 指定订阅 Offset
```
long position(TopicPartition partition) throws SQLException;
Map<TopicPartition, Long> position(String topic) throws SQLException;
Map<TopicPartition, Long> beginningOffsets(String topic) throws SQLException;
Map<TopicPartition, Long> endOffsets(String topic) throws SQLException;
void seek(TopicPartition partition, long offset) throws SQLException;
```
#### 关闭订阅 #### 关闭订阅
```java ```java
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