EhCache 3.1.3 持久化问题

Question

我在 ehcache 中遇到持久性问题。缓存本身在第一次启动时工作正常，但在我重新启动 tomcat servlet 时它不记得旧值。这是我初始化 ehcache 的代码。我没有使用任何 xml.

import org.ehcache.Cache;
import org.ehcache.PersistentCacheManager;
import org.ehcache.Status;
import org.ehcache.config.builders.CacheConfigurationBuilder;
import org.ehcache.config.builders.CacheManagerBuilder;
import org.ehcache.config.builders.ResourcePoolsBuilder;
import org.ehcache.config.units.EntryUnit;
import org.ehcache.config.units.MemoryUnit;

PersistentCacheManager persistentCacheManager =
    CacheManagerBuilder.newCacheManagerBuilder()
            .with(CacheManagerBuilder.persistence("/cache"))
            .withCache("test-cache",
                    CacheConfigurationBuilder.newCacheConfigurationBuilder(
                            Integer.class, String.class,
                            ResourcePoolsBuilder.newResourcePoolsBuilder()
                                    .heap(1, EntryUnit.ENTRIES)
                                    .offheap(1, MemoryUnit.MB)
                                    .disk(20, MemoryUnit.MB)
                    )
            ).build(true);
Cache cache = persistentCacheManager.getCache("test-cache", Integer.class, String.class);

log.info("Cache get 1 before putting: " + cache.get(1));
for(int i = 0; i< 1000; i++) {
    cache.put(i,"Hello");
}
log.info("Cache get 1 after putting: " + cache.get(1));

"before" 日志语句的结果在重新启动后始终为空。

Answer 1

您需要将磁盘资源池声明为持久的。默认情况下不是。

.disk(20, MemoryUnit.MB, true)

那么你的测试就完美了。

包含关闭缓存管理器的完整代码：

import org.ehcache.Cache;
import org.ehcache.PersistentCacheManager;
import org.ehcache.config.units.EntryUnit;
import org.ehcache.config.units.MemoryUnit;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import static org.ehcache.config.builders.CacheConfigurationBuilder.*;
import static org.ehcache.config.builders.CacheManagerBuilder.*;
import static org.ehcache.config.builders.ResourcePoolsBuilder.*;

public class Main {

  private static final Logger log = LoggerFactory.getLogger(Main.class);

  public static void main(String[] args) {
    try(PersistentCacheManager persistentCacheManager =
        newCacheManagerBuilder()
            .with(persistence("cache"))
            .withCache("test-cache",
                newCacheConfigurationBuilder(
                    Integer.class, String.class,
                    newResourcePoolsBuilder()
                        .heap(1, EntryUnit.ENTRIES)
                        .offheap(1, MemoryUnit.MB)
                        .disk(20, MemoryUnit.MB, true)
                )
            ).build(true)) {
      Cache cache = persistentCacheManager.getCache("test-cache", Integer.class, String.class);

      log.info("Cache get 1 before putting: " + cache.get(1));
      for (int i = 0; i < 1000; i++) {
        cache.put(i, "Hello");
      }
      log.info("Cache get 1 after putting: " + cache.get(1));
    }
  }
}

EhCache 3.1.3 持久化问题

EhCache 3.1.3 persistence issue

java

persistence

disk

ehcache