QueryCachingPolicy (Lucene 7.7.0 API)

All Known Implementing Classes:

UsageTrackingQueryCachingPolicy
```
public interface QueryCachingPolicy
```
A policy defining which filters should be cached. Implementations of this class must be thread-safe.

See Also:

UsageTrackingQueryCachingPolicy, LRUQueryCache

WARNING: This API is experimental and might change in incompatible ways in the next release.

Field Summary

Fields
Modifier and Type	Field	Description
`static QueryCachingPolicy`	`ALWAYS_CACHE`	Deprecated. This policy is inefficient as caching too aggressively disables the ability to skip non-interesting documents.

Method Summary

All Methods Instance Methods Abstract Methods
Modifier and Type	Method	Description
`void`	`onUse(Query query)`	Callback that is called every time that a cached filter is used.
`boolean`	`shouldCache(Query query)`	Whether the given `Query` is worth caching.

- Field Detail
  - ALWAYS_CACHE
```
@Deprecated
static final QueryCachingPolicy ALWAYS_CACHE
```
    Deprecated.
    This policy is inefficient as caching too aggressively disables the ability to skip non-interesting documents. See UsageTrackingQueryCachingPolicy.
    
    A simple policy that caches all the provided filters on all segments.
- Method Detail
  - onUse
```
void onUse(Query query)
```
    Callback that is called every time that a cached filter is used. This is typically useful if the policy wants to track usage statistics in order to make decisions.
  - shouldCache
```
boolean shouldCache(Query query)
             throws IOException
```
    Whether the given Query is worth caching. This method will be called by the QueryCache to know whether to cache. It will first attempt to load a DocIdSet from the cache. If it is not cached yet and this method returns true then a cache entry will be generated. Otherwise an uncached scorer will be returned.
    
    Throws:
    
    IOException