NiFi 开发自定义处理器：导入 org.apache.nifi.processors 错误

Question

I am trying to implement a custom processors in NiFi with mvn archetype:generate and I would like to import a class from org.apache.nifi.processors (in particular standard.util.* ), but it gives me error ( cannot be resolved ).

My current workaround is to copy the classes that I want in my package, but what should I do to make it visible directly from the nifi package? Should I modify the pom.xml ? Thanks in advance

The content of the pom.xml is the one generated by the mvn archetype:generate command:

<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>

    <parent>
        <groupId>com.example.nifi</groupId>
        <artifactId>stream-processorr</artifactId>
        <version>1.0-SNAPSHOT</version>
    </parent>

    <artifactId>nifi-StreamProcessor-processors</artifactId>
    <packaging>jar</packaging>

    <dependencies>
        <dependency>
            <groupId>org.apache.nifi</groupId>
            <artifactId>nifi-api</artifactId>
        </dependency>
        <dependency>
            <groupId>org.apache.nifi</groupId>
            <artifactId>nifi-utils</artifactId>
            <version>1.10.0</version>
        </dependency>
        <dependency>
            <groupId>org.apache.nifi</groupId>
            <artifactId>nifi-mock</artifactId>
            <version>1.10.0</version>
            <scope>test</scope>
        </dependency>
        <dependency>
            <groupId>org.slf4j</groupId>
            <artifactId>slf4j-simple</artifactId>
            <scope>test</scope>
        </dependency>
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <scope>test</scope>
        </dependency>
    </dependencies>
</project>

Answer 1

Presumably, and from a pure Maven standpoint, you would likely need to depend on nifi-standard-processors to get that package to resolve. That is where the majority of classes in that package exist. Of course, this depends on the specific class(es) of interest.

As a bit of context from the NiFi project perspective, the package listed is mostly tailored toward helper classes for the processors in the standard bundle. It is typically not a good practice to depend on these in other NAR bundles. However, if you share use case it may make sense to extract these to a separate module for wider use.