refactor: modernize Java example code with Java 17 features#171
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Motivation: Java 17 introduced records, pattern matching for instanceof, and other features that make Java code more concise and readable. The example code contained many verbose data carrier classes and instanceof patterns that can be significantly simplified. Modification: - Convert data carrier classes (commands, events, messages) to Java records in sample applications: ShoppingCart, ClusterClient, ReplicatedCache, VotingService, ThumbsUpCounter - Use pattern matching for instanceof to eliminate explicit casts - Update all field accesses from direct field access to record accessor methods - Remove redundant equals/hashCode/constructor boilerplate Result: Example Java code is more concise and idiomatic for Java 17+, reducing boilerplate while maintaining the same behavior. Net reduction of ~350 lines of code across 6 files. Tests: Not run - sample applications without automated test suite References: None - code modernization
pjfanning
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Jun 18, 2026
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our samples are still pekko 1 based and that probably means also supporting java 8
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Closing this PR as pekko-samples still needs to support Java 8 (pekko 1.x based), which means Java 17 records cannot be used. Thanks @pjfanning for the review. |
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Motivation
Java 17 introduced records, pattern matching for instanceof, and other features that make Java code more concise and readable. The example code contained many verbose data carrier classes and instanceof + explicit cast patterns that can be significantly simplified.
Modification
Files changed:
pekko-sample-persistence-java/: ShoppingCartpekko-sample-distributed-data-java/: ShoppingCart, VotingService, ReplicatedCachepekko-sample-cluster-client-grpc-java/: ClusterClientpekko-sample-persistence-dc-java/: ThumbsUpCounterResult
Example Java code is more concise and idiomatic for Java 17+, reducing boilerplate while maintaining the same behavior. Net reduction of ~350 lines of code across 6 files.
Tests
Not run - sample applications without automated test suite
References
None - code modernization