mjsax commented on code in PR #18314:
URL: https://github.com/apache/kafka/pull/18314#discussion_r1896961093
##########
docs/streams/developer-guide/dsl-api.html:
##########
@@ -3243,6 +3244,177 @@ <h5><a class="toc-backref" href="#id34">KTable-KTable
Foreign-Key
// `Processor` interface, see further down below.
.process(() -> new
PopularPageEmailAlert("[email protected]"));</code></pre>
</div>
+ <div class="section" id="migrating-from-transform-to-process">
+ <h2>
+ <a class="headerlink"
href="#migrating-from-transform-to-process" title="Permalink to this headline">
+ Migrating from transform to process
+ </a>
+ </h2>
+ <div>
+ <p>
+ As of Kafka 4.0, several deprecated methods in the Kafka
Streams API, such as <code>transform</code>,
+ <code>flatTransform</code>, <code>transformValues</code>,
and <code>flatTransformValues</code>, have
+ been removed. These methods have been replaced with the
more versatile <code>process</code> API. This
+ guide provides detailed steps for migrating existing code
to use the new <code>process</code> API and
+ explains the benefits of the changes.
+ </p>
+ <h3>Overview of Changes</h3>
+ <p>The following deprecated methods are no longer available in
Kafka Streams:</p>
+ <ul>
+ <li><code>KStream#transform</code></li>
+ <li><code>KStream#flatTransform</code></li>
+ <li><code>KStream#transformValues</code></li>
+ <li><code>KStream#flatTransformValues</code></li>
+ </ul>
+ <p>The <code>process</code> API now serves as a unified
replacement for all these methods. It simplifies the
+ API surface while maintaining support for both stateless
and stateful operations.</p>
+
+ <h3>Migration Steps</h3>
+
+ <h4>1. Migrate from <code>transform</code> to
<code>process</code></h4>
+
+ <pre class="line-numbers"><code class="language-java">// Before
+KStream<String, String> transformedStream = stream.transform(
+ () -> new CustomTransformer(),
+ "state-store"
+);
+
+// After
+KStream<String, String> processedStream = stream.process(
+ () -> new CustomProcessor(),
+ "state-store"
+);</code></pre>
+
+ <h4>2. Migrate from <code>flatTransform</code> to
<code>process</code></h4>
+ <pre class="line-numbers"><code class="language-java">// Before
+KStream<String, String> flatTransformedStream = stream.flatTransform(
+ () -> new CustomFlatTransformer(),
+ "state-store"
+);
+
+// After
+KStream<String, String> processedStream = stream.process(
+ () -> new Processor<String, String>() {
Review Comment:
The new `api.Processor` has 4 generic, key/value in/out.
--
This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.
To unsubscribe, e-mail: [email protected]
For queries about this service, please contact Infrastructure at:
[email protected]
