[Feature Request]: Modernize legacy DoFn in BatchElementsExample to use parameter injection #40557

What would you like to happen?

In examples/java/src/main/java/org/apache/beam/examples/BatchElementsExample.java, the LogOutput DoFn still uses the legacy ProcessContext in its @ProcessElement method:

@ProcessElement
public void processElement(ProcessContext c) throws Exception { ... }

Issue Priority

Priority: 2 (default / most feature requests should be filed as P2)

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