Same key computes multiple times

Code reviewConcurrencyMid–Senior~28 min

Review this Java in-memory cache with lazy compute.

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 28 min

Mark a line and say what kind of problem it is.0 findings

1public class ResultCache {

2 private final Map<String, BigInteger> cache = new ConcurrentHashMap<>();

4 public BigInteger get(String key) {

5 if (!cache.containsKey(key)) {

6 BigInteger v = expensiveCompute(key); // seconds long

7 cache.put(key, v);

8 }

9 return cache.get(key);

10 }

11}

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