Flink: The program's entry point class not found in the jar file

Question

I'm trying to deploy a Flink stateful function as a flink jar and I followed the instruction here. However I'm getting the error saying that the program entry point class was not found in the jar even after I added the dependency in my pom.

Running:

bin/flink run -c org.apache.flink.statefun.flink.core.StatefulFunctionsJob flink-statefun/statefun-examples/statefun-greeter-example/target/statefun-greeter-example-2.3-SNAPSHOT.jar

Producing the following error:

org.apache.flink.client.program.ProgramInvocationException: The program's entry point class 'org.apache.flink.statefun.flink.core.StatefulFunctionsJob' was not found in the jar file.
    at org.apache.flink.client.program.PackagedProgram.loadMainClass(PackagedProgram.java:389)
    at org.apache.flink.client.program.PackagedProgram.<init>(PackagedProgram.java:139)
    at org.apache.flink.client.program.PackagedProgram.<init>(PackagedProgram.java:61)
    at org.apache.flink.client.program.PackagedProgram$Builder.build(PackagedProgram.java:557)
    at org.apache.flink.client.cli.CliFrontend.buildProgram(CliFrontend.java:726)
    at org.apache.flink.client.cli.CliFrontend.getPackagedProgram(CliFrontend.java:242)
    at org.apache.flink.client.cli.CliFrontend.run(CliFrontend.java:223)
    at org.apache.flink.client.cli.CliFrontend.parseParameters(CliFrontend.java:916)
    at org.apache.flink.client.cli.CliFrontend.lambda$main$10(CliFrontend.java:992)
    at org.apache.flink.runtime.security.contexts.NoOpSecurityContext.runSecured(NoOpSecurityContext.java:30)
    at org.apache.flink.client.cli.CliFrontend.main(CliFrontend.java:992)
Caused by: java.lang.ClassNotFoundException: org.apache.flink.statefun.flink.core.StatefulFunctionsJob
    at java.net.URLClassLoader.findClass(URLClassLoader.java:382)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:418)
    at org.apache.flink.util.FlinkUserCodeClassLoader.loadClassWithoutExceptionHandling(FlinkUserCodeClassLoader.java:61)
    at org.apache.flink.util.ChildFirstClassLoader.loadClassWithoutExceptionHandling(ChildFirstClassLoader.java:65)
    at org.apache.flink.util.FlinkUserCodeClassLoader.loadClass(FlinkUserCodeClassLoader.java:48)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:351)
    at java.lang.Class.forName0(Native Method)
    at java.lang.Class.forName(Class.java:348)
    at org.apache.flink.client.program.PackagedProgram.loadMainClass(PackagedProgram.java:387)
    ... 10 more

Here is my pom.xml

<?xml version="1.0" encoding="UTF-8"?>
<!--
Licensed to the Apache Software Foundation (ASF) under one
or more contributor license agreements.  See the NOTICE file
distributed with this work for additional information
regarding copyright ownership.  The ASF licenses this file
to you under the Apache License, Version 2.0 (the
"License"); you may not use this file except in compliance
with the License.  You may obtain a copy of the License at
  http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing,
software distributed under the License is distributed on an
"AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
KIND, either express or implied.  See the License for the
specific language governing permissions and limitations
under the License.
-->
<project xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xmlns="http://maven.apache.org/POM/4.0.0"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <parent>
        <artifactId>statefun-examples</artifactId>
        <groupId>org.apache.flink</groupId>
        <version>2.3-SNAPSHOT</version>
        <relativePath>..</relativePath>
    </parent>
    <modelVersion>4.0.0</modelVersion>

    <artifactId>statefun-greeter-example</artifactId>

    <dependencies>
        
        <dependency>
            <groupId>org.apache.flink</groupId>
            <artifactId>statefun-sdk</artifactId>
            <version>${project.version}</version>
        </dependency>
        <dependency>
            <groupId>org.apache.flink</groupId>
            <artifactId>statefun-kafka-io</artifactId>
            <version>${project.version}</version>
        </dependency>

        <dependency>
            <groupId>org.apache.flink</groupId>
            <artifactId>statefun-flink-core</artifactId>
            <version>${project.version}</version>
            <exclusions>
                <!-- The following exclusion is needed since this artifacts pulls two different versions
                     of slf4j, and thus failing the maven convergence plugging.
                 -->
                <exclusion>
                    <groupId>org.slf4j</groupId>
                    <artifactId>slf4j-api</artifactId>
                </exclusion>
                <exclusion>
                    <groupId>com.google.protobuf</groupId>
                    <artifactId>protobuf-java</artifactId>
                </exclusion>
            </exclusions>
        </dependency>
        <dependency>
            <groupId>org.apache.flink</groupId>
            <artifactId>statefun-flink-distribution</artifactId>
            <version>${project.version}</version>
            <exclusions>
                <!-- The following exclusion is needed since this artifacts pulls two different versions
                     of slf4j, and thus failing the maven convergence plugging.
                 -->
                <exclusion>
                    <groupId>org.slf4j</groupId>
                    <artifactId>slf4j-api</artifactId>
                </exclusion>
                <exclusion>
                    <groupId>com.google.protobuf</groupId>
                    <artifactId>protobuf-java</artifactId>
                </exclusion>
            </exclusions>
        </dependency>
        <dependency>
            <groupId>com.google.protobuf</groupId>
            <artifactId>protobuf-java</artifactId>
            <version>3.8.0</version>
        </dependency>
        
    </dependencies>

    <build>
        <plugins>
            <plugin>
                <groupId>com.github.os72</groupId>
                <artifactId>protoc-jar-maven-plugin</artifactId>
                <version>${protoc-jar-maven-plugin.version}</version>
            </plugin>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-javadoc-plugin</artifactId>
                <configuration>
                    <excludePackageNames>org.apache.flink.statefun.examples.greeter.generated</excludePackageNames>
                </configuration>
            </plugin>
        </plugins>
    </build>
    
</project>

The original version of the pom file can be found here here. It seems that adding the extra dependency of statefun-flink-distribution has no effect. Any suggestions?

Answer 1

When you are submitting a Flink job, you will also need to provide the dependencies for that Job. In this case the data stream sdk jar. You can create a jar with dependencies with a shade plugin.