Code RoomJackson polymorphic deserialization
HardPrep Room Coding #1893

Jackson polymorphic deserialization

Code reviewCode quality & reviewSenior–Staff~35 min

Review this Java JSON config endpoint using Jackson.

What a strong answer looks like

Separate real bugs from style. Rank issues by severity, point at the root cause rather than the symptom, and suggest a concrete fix, specific and kind.

0:00 of about 35 min
Mark a line and say what kind of problem it is.0 findings
1public class ConfigService {
2 private final ObjectMapper mapper = new ObjectMapper();
3 
4 public ConfigService() {
5 // Allow polymorphic config objects to round-trip by type
6 mapper.enableDefaultTyping();
7 }
8 
9 public Config load(String json) throws IOException {
10 return mapper.readValue(json, Config.class);
11 }
12}
13// json is the raw request body from POST /api/config
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