spring boot Cache 사용, 모든 캐시 내용 출력 해 보기

1. 설정

그래이들

implementation 'org.springframework.boot:spring-boot-starter-cache'

config 설정

@Configuration
@EnableCaching
public class CacheConfig {
}

 

2. 사용

캐시 할 내용에 @Cacheable

캐시 삭제시 @CacheEvict

캐시 업데이트 시 @Cacheput

 

import org.springframework.cache.Cache;
import org.springframework.cache.CacheManager;
import org.springframework.cache.annotation.CacheEvict;
import org.springframework.cache.annotation.Cacheable;
import org.springframework.stereotype.Service;

import java.util.Collection;
import java.util.Random;
import java.util.concurrent.ConcurrentHashMap;

@Service
public class CacheService {

    private final CacheManager cacheManager;

    public CacheService(CacheManager cacheManager) {
        this.cacheManager = cacheManager;
    }

    @Cacheable(value = "random", key = "#id")
    public String cacheRandom( String id) {
        Random random = new Random();
        return id + "_" + random.nextInt(100);
    }

    @CacheEvict(value = "random", key = "#id")
    public void cacheRandomEvict(String id) {

    }

    public void cacheAll() {
        Collection<String> cacheNames = cacheManager.getCacheNames();
        for (String cacheName : cacheNames) {
            System.out.println("cacheName = " + cacheName);
        }
        Cache random = cacheManager.getCache("random");
        System.out.println("random = " + random);

        for (String cacheName : cacheNames) {
            Cache cache = cacheManager.getCache(cacheName);

            if (cache != null) {
                ConcurrentHashMap nativeCache = (ConcurrentHashMap) cache.getNativeCache();
                System.out.println("nativeCache = " + nativeCache);
                System.out.println("nativeCache type = " + nativeCache.getClass().getName() );
                ConcurrentHashMap cacheMap = (ConcurrentHashMap) nativeCache;
                cacheMap.forEach((strKey, strValue)->{
                    System.out.println( strKey +" : "+ strValue );
                });
            }
        }

    }
}

CacheManger (구현체 ConcurrentMapCacheManager )를 통해서 캐시 이름 목록을 가져오고

다시 이름으로 Cache 를 가져오고

가져온 캐시를 ConcurrentHashMap으로 변환 후 순회한다.