Missing rules when using expirable maps/caches from popular open source libraries

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Assessment

Difficulty
4/5
Estimated time
3-5 days
Newbie friendliness
48/100
Issue type
Feature
Clarity
Mostly clear
Activity status
Stale
Tech stack
aws, java
Domain
devtools

Research direction

Start by locating the repository's Java rule definitions and tests for SnapStart-related warnings. Review how checks identify library and method usage, then cover Guava expireAfterAccess/expireAfterWrite and ExpiringMap expiration variants. Done means the relevant expirable-cache patterns produce a warning while non-expiring cache usage remains unaffected.

Written by the indexing model from the issue text.

Description

In case the expirable cache is initialized in the constructor of the Lambda class and some entries are put as well it may happen that the entries are not there anymore after the SnapStart snapshot is restored. The should be a warning of usage of time-based cached with the SnapStart is enabled.

In particular I'm thinking of the usage of 2 popular open source libraries:

  • Google Guava ( artifact id guava and group id com.google.guava) and the code like this

myCache = CacheBuilder.newBuilder().expireAfterAccess(3600, TimeUnit.SECONDS) .build();
myCache.put("key", "value");

  • Using artifact id expiringmap and the group id net.jodah and the code like this

expiredMap = ExpiringMap.builder().expiration(3600, TimeUnit.SECONDS).build();
expiredMap.put("key", "value");

I know that it's difficult to spot such use cases because both open source libraries offer standard and not expirable caches. But the invocation of the methods like CacheBuilder.newBuilder().expireAfterAccess/expireAfterWrite or multiple variations of methods ExpiringMap.builder().expiration* when creating the cache using these open source tools is a clear indication of the creation of expirable cache.

Dominant language
Java
Stars
53
Forks
10
PR merge metrics
No merged PRs in 30d

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