CacheFilter (Apache Dubbo 2.7.7 API)

java.lang.Object
- org.apache.dubbo.cache.filter.CacheFilter

All Implemented Interfaces:

Filter
```
@Activate(group={"consumer","provider"},
          value="cache")
public class CacheFilter
extends Object
implements Filter
```
CacheFilter is a core component of dubbo.Enabling cache key of service,method,consumer or provider dubbo will cache method return value. Along with cache key we need to configure cache type. Dubbo default implemented cache types are
lur
threadlocal
jcache
expiring

   e.g. 1)<dubbo:service cache="lru" />
        2)<dubbo:service /> <dubbo:method name="method2" cache="threadlocal" /> <dubbo:service/>
        3)<dubbo:provider cache="expiring" />
        4)<dubbo:consumer cache="jcache" />

If cache type is defined in method level then method level type will get precedence. According to above provided
example, if service has two method, method1 and method2, method2 will have cache type as threadlocal where others will
be backed by lru

See Also:: Filter, LruCacheFactory, LruCache, JCacheFactory, JCache, ThreadLocalCacheFactory, ThreadLocalCache, ExpiringCacheFactory, ExpiringCache

Nested Class Summary
- Nested classes/interfaces inherited from interface org.apache.dubbo.rpc.Filter
  Filter.Listener

Constructor Summary

Constructors
Constructor and Description

CacheFilter()

Constructors
Constructor and Description
`CacheFilter()`

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`Result`	`invoke(Invoker<?> invoker, Invocation invocation)` If cache is configured, dubbo will invoke method on each method call.
`void`	`setCacheFactory(CacheFactory cacheFactory)` Dubbo will populate and set the cache factory instance based on service/method/consumer/provider configured cache attribute value.

Methods inherited from class java.lang.Object
equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Constructor Detail
  - CacheFilter
```
public CacheFilter()
```
- Method Detail
  - setCacheFactory
```
public void setCacheFactory(CacheFactory cacheFactory)
```
    Dubbo will populate and set the cache factory instance based on service/method/consumer/provider configured cache attribute value. Dubbo will search for the class name implementing configured cache in file org.apache.dubbo.cache.CacheFactory under META-INF sub folders.
    
    Parameters:
    
    cacheFactory - instance of CacheFactory based on cache type
  - invoke
```
public Result invoke(Invoker<?> invoker,
                     Invocation invocation)
              throws RpcException
```
    If cache is configured, dubbo will invoke method on each method call. If cache value is returned by cache store then it will return otherwise call the remote method and return value. If remote method's return value has error then it will not cache the value.
    
    Specified by:
    
    invoke in interface Filter
    
    Parameters:
    
    invoker - service
    
    invocation - invocation.
    
    Returns:
    
    Cache returned value if found by the underlying cache store. If cache miss it will call target method.
    
    Throws:
    
    RpcException

Class CacheFilter

Nested Class Summary

Nested classes/interfaces inherited from interface org.apache.dubbo.rpc.Filter

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Constructor Detail

CacheFilter

Method Detail

setCacheFactory

invoke