How to enable ehCache (3.x) in SpringMVC (5.x) project

Question

In our project we use the ehcache 2.x and now we want to migrate to 3.x but somehow I fail tremendously. In 2.x we have the configuration in ehcache.xml. To what I read is that I need to change the content as well when using 3.x.

But first of all I have no clue how to wire the Cache by itself. I have

@EnableCaching
@Configuration
public class CacheConf {
  @Bean
  public CacheManager cacheManager() {
    final CacheManagerBuilder<org.ehcache.CacheManager> ret = CacheManagerBuilder.newCacheManagerBuilder();
    ret.withCache("properties", getPropCache());
    ret.withCache("propertyTypes", getPropCache());
    return (CacheManager) ret.build(true);
  }
....

But this configuration I get a java.lang.ClassCastException: org.ehcache.core.EhcacheManager cannot be cast to org.springframework.cache.CacheManager which means that I cannot set the ehcache properly.

Note: In 2.x we configured different types of caches, more or less due to the expiration period - and since other object types are stored therein.

Hints to get it running, cause I didn't find a working sample with Spring 5 and ehcache 3.x? Best would be a config without xml!

Answer 1

The Ehcache CacheManager isn't a Spring CacheManager. This is why you get the ClassCastException.

Ehcache 3 is JSR107 (JCache) compliant. So Spring will connect to it using that.

You will find an example here and a simpler one in Spring Boot petclinic.

If I take your example, you will do something like

@EnableCaching
@Configuration
public class CacheConf {
    @Bean
    public CacheManager cacheManager() {
        EhcacheCachingProvider provider = (EhcacheCachingProvider) Caching.getCachingProvider();

        Map<String, CacheConfiguration<?, ?>> caches = new HashMap<>();
        caches.put("properties", getPropCache());
        caches.put("propertyTypes", getPropCache());

        DefaultConfiguration configuration = new DefaultConfiguration(caches, provider.getDefaultClassLoader());
        return new JCacheCacheManager(provider.getCacheManager(provider.getDefaultURI(), configuration));
    }

  private CacheConfiguration<?, ?> getPropCache() {
    // access to the heap() could be done directly cause this returns what is required!
    final ResourcePoolsBuilder res = ResourcePoolsBuilder.heap(1000);
    // Spring does not allow anything else than Objects...
    final CacheConfigurationBuilder<Object, Object> newCacheConfigurationBuilder = CacheConfigurationBuilder
        .newCacheConfigurationBuilder(Object.class, Object.class, res);
    return newCacheConfigurationBuilder.build();
  }
}