backend/src/main/java/nju/seec/helper/util/GuavaCacheUtil.java

package nju.seec.helper.util;

import com.google.common.cache.Cache;
import com.google.common.cache.CacheBuilder;
import com.google.common.collect.ImmutableMap;
import org.springframework.beans.factory.BeanNameAware;
import org.springframework.beans.factory.InitializingBean;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.stereotype.Component;
import org.springframework.util.StringUtils;

import java.util.Collection;
import java.util.List;
import java.util.Map;
import java.util.concurrent.TimeUnit;
import java.util.stream.Collectors;
@Component
public class GuavaCacheUtil {
    private Cache<Object, Object> cache;

    @Value("${guavaCache.maximumSize}")
    private Long maximumSize=1000L;

    @Value("${guavaCache.expireAfterAccessInSeconds}")
    private Long expireAfterAccessInSeconds=1800L;

    @Value("${guavaCache.expireAfterWriteInSeconds}")
    private Long expireAfterWriteInSeconds=3600L;

    public GuavaCacheUtil() {
        CacheBuilder<Object, Object> builder = CacheBuilder.newBuilder();
        builder.maximumSize(maximumSize);
        builder.expireAfterAccess(expireAfterAccessInSeconds, TimeUnit.SECONDS);
        builder.expireAfterWrite(expireAfterWriteInSeconds, TimeUnit.SECONDS);
        cache = builder.build();
    }

    public void set(String cacheName, String key, Object value) {
        cache.put(combineKey(cacheName,key),value);
    }

    public void setAll(String cacheName, Map<String,Object> putAll) {
        final Map<String, Object> all = putAll.entrySet().stream().collect(Collectors.toMap(entry -> {
            return combineKey(cacheName , entry.getKey());
        }, Map.Entry::getValue));
        cache.putAll(all);
    }
    public Object get(String cacheName, String key) {
        return cache.getIfPresent(combineKey(cacheName,key));
    }

    public ImmutableMap<Object, Object> multiGet(String cacheName, Collection<String> keys) {
        Collection<String> body=keys.stream().map(s->combineKey(cacheName,s)).collect(Collectors.toList());
        return cache.getAllPresent(body);
    }

    public void remove(String cacheName, String key) {
        cache.invalidate(combineKey(cacheName,key));
    }

    private String combineKey(String cacheName, String key){
        return cacheName + ":" + key;
    }
}