如何在spring boot中获取spring缓存大小？

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.cache.CacheManager;
import org.springframework.cache.concurrent.ConcurrentMapCache;
import org.springframework.stereotype.Component;

@Component
public class CacheSizeUtil {
    
    @Autowired
    private CacheManager cacheManager;
    
    public int getCacheSize(String cacheName) {
        ConcurrentMapCache cache = (ConcurrentMapCache) cacheManager.getCache(cacheName);
        return cache.getNativeCache().size();
    }
}

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RestController;

@RestController
public class CacheController {
    
    @Autowired
    private CacheSizeUtil cacheSizeUtil;
    
    @GetMapping("/cache/{cacheName}/size")
    public int getCacheSize(@PathVariable String cacheName) {
        return cacheSizeUtil.getCacheSize(cacheName);
    }
}