fix examples on website (#31066)

* add DataflowRunner in wordCount run command with Gradle

add DataflowRunner in wordCount run command with Gradle

* Update dataflow.md to update mvn package and run commands

Update dataflow.md to update mvn package and run commands

website/www/site/content/en/documentation/runners/dataflow.md

@@ -101,7 +101,7 @@ Then, add the mainClass name in the Maven JAR plugin.
 {{< /highlight >}}
 
 {{< paragraph class="language-java" >}}
-After running <code>mvn package</code>, run <code>ls target</code> and you should see (assuming your artifactId is `beam-examples` and the version is 1.0.0) the following output.
+After running <code>mvn package -Pdataflow-runner</code>, run <code>ls target</code> and you should see (assuming your artifactId is `beam-examples` and the version is 1.0.0) the following output.
 {{< /paragraph >}}
 
 {{< highlight java >}}
@@ -117,7 +117,8 @@ java -jar target/beam-examples-bundled-1.0.0.jar \
   --runner=DataflowRunner \
   --project=<YOUR_GCP_PROJECT_ID> \
   --region=<GCP_REGION> \
-  --tempLocation=gs://<YOUR_GCS_BUCKET>/temp/
+  --tempLocation=gs://<YOUR_GCS_BUCKET>/temp/ \
+  --output=gs://<YOUR_GCS_BUCKET>/output
 {{< /highlight >}}
 
 ## Pipeline options for the Cloud Dataflow Runner {#pipeline-options}

website/www/site/content/en/get-started/quickstart-java.md

@@ -297,7 +297,7 @@ TODO: document Spark on Gradle: https://github.com/apache/beam/issues/21502
 {{< runner dataflow >}}
 gradle clean execute -DmainClass=org.apache.beam.examples.WordCount \
     --args="--project=<your-gcp-project> --inputFile=gs://apache-beam-samples/shakespeare/* \
-    --output=gs://<your-gcs-bucket>/counts" -Pdataflow-runner
+    --output=gs://<your-gcs-bucket>/counts --runner=DataflowRunner" -Pdataflow-runner
 {{< /runner >}}
 {{< runner samza>}}
 TODO: document Samza on Gradle: https://github.com/apache/beam/issues/21500