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Merge pull request #3084 from taosdata/TD-1111_feature 

Td 1111 feature
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Shengliang Guan 2020-08-15 16:01:24 +08:00 committed by GitHub
parent bfac4364e7 5ee411fe55
commit 321aa289f3
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1 changed files with 8 additions and 22 deletions
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@ -329,14 +329,12 @@ Query OK, 5 row(s) in set (0.004896s)
```java ```java
public class SubscribeDemo { public class SubscribeDemo {
private static final String topic = "topic_meter_current_bg_10"; private static final String topic = "topic-meter-current-bg-10";
private static final String sql = "select * from meters where current > 10"; private static final String sql = "select * from meters where current > 10";
public static void main(String[] args) { public static void main(String[] args) {
Connection connection = null; Connection connection = null;
Statement statement = null;
TSDBSubscribe subscribe = null; TSDBSubscribe subscribe = null;
long subscribeId = 0;
try { try {
// 加载驱动 // 加载驱动
@ -347,16 +345,12 @@ public class SubscribeDemo {
properties.setProperty(TSDBDriver.PROPERTY_KEY_TIME_ZONE, "UTC-8"); properties.setProperty(TSDBDriver.PROPERTY_KEY_TIME_ZONE, "UTC-8");
String jdbcUrl = "jdbc:TAOS://127.0.0.1:6030/power?user=root&password=taosdata"; String jdbcUrl = "jdbc:TAOS://127.0.0.1:6030/power?user=root&password=taosdata";
connection = DriverManager.getConnection(jdbcUrl, properties); connection = DriverManager.getConnection(jdbcUrl, properties);
System.out.println("create the connection"); // 创建Subscribe，topic为主题名称，sql为查询语句，restar为true代表每次订阅消费历史数据
// 创建Subscribe subscribe = ((TSDBConnection) connection).subscribe(topic, sql, true);
subscribe = ((TSDBConnection) connection).createSubscribe();
// subscribe订阅topic，topic为主题名称，sql为查询语句，restart代表是否每次订阅接受历史数据
subscribeId = subscribe.subscribe(topic, sql, true);
System.out.println("create a subscribe topic: " + topic + "@[" + subscribeId + "]");
int count = 0; int count = 0;
while (true) { while (true) {
// 消费数据 // 消费数据
TSDBResultSet resultSet = subscribe.consume(subscribeId); TSDBResultSet resultSet = subscribe.consume();
// 打印结果集 // 打印结果集
if (resultSet != null) { if (resultSet != null) {
ResultSetMetaData metaData = resultSet.getMetaData(); ResultSetMetaData metaData = resultSet.getMetaData();
@ -377,18 +371,10 @@ public class SubscribeDemo {
e.printStackTrace(); e.printStackTrace();
} finally { } finally {
try { try {
if (null != subscribe && subscribeId != 0) { if (null != subscribe)
subscribe.unsubscribe(subscribeId, true); subscribe.close(true);
System.out.println("unsubscribe the top@[" + subscribeId + "]"); if (connection != null)
} connection.close();
if (statement != null) {
statement.close();
System.out.println("close the statement.");
}
if (connection != null) {
connection.close();
System.out.println("close the connection.");
}
} catch (SQLException throwables) { } catch (SQLException throwables) {
throwables.printStackTrace(); throwables.printStackTrace();
} }