Flink写入MySQL简单示例
1. 整体流程
首先我们来看一下整个实现“Flink写入MySQL简单示例”的流程:
erDiagram
CUSTOMER ||--o| PURCHASE : has
PURCHASE ||--|| PRODUCT : contains
2. 步骤及代码实现
步骤一:创建一个Flink项目
首先需要创建一个Flink项目,可以使用IDEA等工具,确保项目可以正常运行。
步骤二:导入依赖
在项目的pom.xml文件中导入Flink和MySQL连接器的依赖:
```xml
<dependency>
<groupId>org.apache.flink</groupId>
<artifactId>flink-java</artifactId>
<version>${flink.version}</version>
</dependency>
<dependency>
<groupId>org.apache.flink</groupId>
<artifactId>flink-streaming-java_${scala.binary.version}</artifactId>
<version>${flink.version}</version>
</dependency>
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<version>${mysql.version}</version>
</dependency>
#### 步骤三:编写Flink程序
编写一个简单的Flink程序,读取数据流,并写入MySQL数据库:
```java
```java
DataStream<String> inputStream = env.socketTextStream("localhost", 9999);
SingleOutputStreamOperator<Tuple2<String, Integer>> dataStream = inputStream
.flatMap(new Tokenizer())
.keyBy(0)
.sum(1);
dataStream.addSink(new MySQLSink());
#### 步骤四:编写自定义Sink函数
编写一个自定义的Sink函数,将数据写入MySQL数据库:
```java
```java
public class MySQLSink extends RichSinkFunction<Tuple2<String, Integer>> {
private Connection connection;
private PreparedStatement preparedStatement;
@Override
public void open(Configuration parameters) throws Exception {
super.open(parameters);
connection = DriverManager.getConnection("jdbc:mysql://localhost:3306/test", "root", "password");
preparedStatement = connection.prepareStatement("INSERT INTO word_count(word, count) VALUES (?, ?)");
}
@Override
public void invoke(Tuple2<String, Integer> value, Context context) throws Exception {
preparedStatement.setString(1, value.f0);
preparedStatement.setInt(2, value.f1);
preparedStatement.executeUpdate();
}
@Override
public void close() throws Exception {
super.close();
if (preparedStatement != null) {
preparedStatement.close();
}
if (connection != null) {
connection.close();
}
}
}
### 3. 总结
通过以上步骤,我们实现了一个简单的Flink写入MySQL的示例。希望这篇文章可以帮助你快速入门Flink和MySQL的集成,加快你的学习和工作进度。如果遇到问题,可以随时咨询我。祝你学习顺利!