C0urante commented on code in PR #13433: URL: https://github.com/apache/kafka/pull/13433#discussion_r1152508079
########## connect/api/src/main/java/org/apache/kafka/connect/data/ConnectSchema.java: ########## @@ -289,29 +291,202 @@ public ConnectSchema schema() { @Override public boolean equals(Object o) { if (this == o) return true; - if (o == null || getClass() != o.getClass()) return false; - ConnectSchema schema = (ConnectSchema) o; - return Objects.equals(optional, schema.optional) && - Objects.equals(version, schema.version) && - Objects.equals(name, schema.name) && - Objects.equals(doc, schema.doc) && - Objects.equals(type, schema.type) && - Objects.deepEquals(defaultValue, schema.defaultValue) && - Objects.equals(fields, schema.fields) && - Objects.equals(keySchema, schema.keySchema) && - Objects.equals(valueSchema, schema.valueSchema) && - Objects.equals(parameters, schema.parameters); + if (!(o instanceof Schema)) return false; + Schema schema = (Schema) o; + return equals(this, schema); + } + + private static boolean equals(Schema left, Schema right) { + return equals(left, right, new IdentityHashMap<>()); + } + + private static boolean equals(Schema left, Schema right, IdentityHashMap<Schema, Schema> equivalentSchemas) { + if (left == right) + return true; + + if (equivalentSchemas.containsKey(left)) { + // Use referential equality because object equality might cause a stack overflow + return equivalentSchemas.get(left) == right; + } + + boolean shallowMatches = Objects.equals(left.isOptional(), right.isOptional()) && + Objects.equals(left.version(), right.version()) && + Objects.equals(left.name(), right.name()) && + Objects.equals(left.doc(), right.doc()) && + Objects.equals(left.type(), right.type()) && + Objects.equals(left.parameters(), right.parameters()); + if (!shallowMatches) + return false; + + // Avoid mutating the passed-in map, since that may interfere with recursive calls higher up the stack + IdentityHashMap<Schema, Schema> equivalentSchemasCopy = new IdentityHashMap<>(equivalentSchemas); Review Comment: I've looked at the Avro code base and they seem to use basically that approach: a single set of equivalent schema pairs is shared across stack frames and consecutive calls during a single top-level invocation of `equals`. I also believe that this should be safe. I'm happy to share an in-depth proof if anyone wants that particular wall of text, but I'd rather save the effort if we all agree that this should be acceptable. -- 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: jira-unsubscr...@kafka.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org