WSO2 CEP，创建扩展功能

2 回答

• 1

  尝试这样的事情：

  import org.wso2.siddhi.core.config.SiddhiContext;
  import org.wso2.siddhi.core.executor.function.FunctionExecutor;
  import org.wso2.siddhi.query.api.definition.Attribute;
  import org.wso2.siddhi.query.api.extension.annotation.SiddhiExtension;
  
  @SiddhiExtension(namespace = "testNamespace", function = "testFunction")
  public class Test extends FunctionExecutor {
      Attribute.Type returnType;
  
      @Override
      public void init(Attribute.Type[] types, SiddhiContext siddhiContext) { }
  
      @Override
      protected Object process(Object object) {
          Object[] arrayObject;
          int param1 = 0;
          int param2 = 0;
          if (object instanceof Object[]) { // if you pass  params  into yours function in executionPlan, you will have arrayObject (remember about order)
              arrayObject = (Object[]) object;
              param1 = (Integer) arrayObject[0];
              param2 = (Integer) arrayObject[1];
          }
          return (param1 + param2);
      }
  
      @Override
      public void destroy() { }
  
      @Override
      public Attribute.Type getReturnType() {
          return returnType.INT; //type of what you want to return (STRING,  INT,  LONG,  FLOAT,  DOUBLE,  BOOL,  TYPE) or null <-- but then it doesn not make sense
      }
  }
  

  回复于 2024-04-27T12:39:11+08:00
• 1

  您可以使用以下链接的指南来了解如何在siddhi查询中使用扩展名 .

  https://docs.wso2.com/display/CEP310/Writing+a+Custom+Function

  要获得对项目的siddhi扩展依赖项，请在pom.xml中使用以下存储库和依赖项

  <repositories>
      <repository>
          <id>wso2-maven2-repository</id>
          <name>WSO2 Maven2 Repository</name>
          <url>http://dist.wso2.org/maven2</url>
      </repository>
  </repositories>
  
   <dependency>
          <groupId>org.wso2.siddhi</groupId>
          <artifactId>siddhi-core</artifactId>
          <version>2.0.0-wso2v4</version>
   </dependency>
  

  回复于 2024-04-27T12:39:11+08:00