guava caches

CachesTest.java

package io.terminus.neverest.notice.dao.site.caches;

import com.google.common.cache.Cache;
import com.google.common.cache.CacheBuilder;
import com.google.common.cache.CacheLoader;
import com.google.common.cache.LoadingCache;
import org.junit.Test;

import java.util.concurrent.Callable;

/**
 * Created by Wang Lichao at 16/1/23 21:34.
 * Desc：
 *   回收的参数
 *   1. 大小的设置：CacheBuilder.maximumSize(long)  CacheBuilder.weigher(Weigher)  CacheBuilder.maxumumWeigher(long)
 *　　2. 时间：expireAfterAccess(long, TimeUnit) expireAfterWrite(long, TimeUnit)
 *　　3. 引用：CacheBuilder.weakKeys() CacheBuilder.weakValues()  CacheBuilder.softValues()
 *　　4. 明确的删除：invalidate(key)  invalidateAll(keys)  invalidateAll()
 *　　5. 删除监听器：CacheBuilder.removalListener(RemovalListener)
 *
 *   refresh机制：
 *　　1. LoadingCache.refresh(K)  在生成新的value的时候，旧的value依然会被使用。
 *　　2. CacheLoader.reload(K, V) 生成新的value过程中允许使用旧的value
 *　　3. CacheBuilder.refreshAfterWrite(long, TimeUnit) 自动刷新cache
 *
 *   http://www.cnblogs.com/peida/p/Guava_Cache.html
 */
public class CachesTest {


    @Test
    public void TestLoadingCache() throws Exception{
        LoadingCache<String,String> cahceBuilder= CacheBuilder
                .newBuilder()
                .build(new CacheLoader<String, String>(){
                    @Override
                    public String load(String key) throws Exception {
                        String strProValue="hello "+key+"!";
                        return strProValue;
                    }

                });

        System.out.println("jerry value:"+cahceBuilder.apply("jerry"));
        System.out.println("jerry value:"+cahceBuilder.get("jerry"));
        System.out.println("peida value:"+cahceBuilder.get("peida"));
        System.out.println("peida value:"+cahceBuilder.apply("peida"));
        System.out.println("lisa value:"+cahceBuilder.apply("lisa"));
        cahceBuilder.put("harry", "ssdded");
        System.out.println("harry value:"+cahceBuilder.get("harry"));
    }

    @Test
    public void testcallableCache()throws Exception{
        Cache<String, String> cache = CacheBuilder.newBuilder().maximumSize(1000).build();
        String resultVal = cache.get("jerry", new Callable<String>() {
            public String call() {
                String strProValue="hello "+"jerry"+"!";
                return strProValue;
            }
        });
        System.out.println("jerry value : " + resultVal);

        resultVal = cache.get("peida", new Callable<String>() {
            public String call() {
                String strProValue="hello "+"peida"+"!";
                return strProValue;
            }
        });
        System.out.println("peida value : " + resultVal);
    }

}