Apache Beam 执行

Question

I'm following this example but in the step: Run WordCount , throught direct command

$ mvn compile exec:java -Dexec.mainClass=org.apache.beam.examples.WordCount \
 -Dexec.args="--inputFile=pom.xml --output=counts" -Pdirect-runner

And finally I have this error:

[INFO] -----------------------------------------------------------------------

[INFO] BUILD FAILURE

[INFO] ------------------------------------------------------------------------

[INFO] Total time: 12.065 s

[INFO] Finished at: 2018-10-02T17:36:05+02:00

[INFO] ------------------------------------------------------------------------

[ERROR] Failed to execute goal org.codehaus.mojo:exec-maven-plugin:1.6.0:java (default-cli) on project word-count-beam: An exception occured while executing the Java class. java.lang.UnsupportedOperationException: Cannot define class using reflection: Could not find sun.misc.Unsafe -> [Help 1]

[ERROR]

[ERROR] To see the full stack trace of the errors, re-run Maven with the -e switch.

[ERROR] Re-run Maven using the -X switch to enable full debug logging.


[ERROR] For more information about the errors and possible solutions, please read the following articles:

[ERROR] [Help 1] http://cwiki.apache.org/confluence/display/MAVEN/MojoExecutionException

Answer 1

You need to use the Java Development Kit (JDK) version 8 . Verify that the JAVA_HOME environment variable is set and points to your JDK installation.

To understand this change better, read:

• The official Feature Request JEP 260: Encapsulate Most Internal APIs .
• Understanding sun.misc.Unsafe