## Uses of Class
com.fasterxml.jackson.databind.util.LRUMap

Packages that use LRUMap
Package | Description
--- | ---
com.fasterxml.jackson.databind.introspect | Functionality needed for Bean introspection, required for detecting accessors and mutators for Beans, as well as locating and handling method annotations.
com.fasterxml.jackson.databind.type | Package that contains concrete implementations of `JavaType`, as well as the factory (`TypeFactory`) for constructing instances from various input data types (like `Class`, `Type`) and programmatically (for structured types, arrays, `List`s and `Map`s).
com.fasterxml.jackson.databind.util | Utility classes for Mapper package.

### Uses of LRUMap in com.fasterxml.jackson.databind.introspect

Fields in com.fasterxml.jackson.databind.introspect declared as LRUMap
Modifier and Type | Field and Description
--- | ---
`protected LRUMap<Class<?>,Boolean>` | JacksonAnnotationIntrospector.`_annotationsInside` Since introspection of annotation types is a performance issue in some use cases (rare, but do exist), let's try a simple cache to reduce need for actual meta-annotation introspection.
`protected LRUMap<JavaType,BasicBeanDescription>` | BasicClassIntrospector.`_cachedFCA` Looks like 'forClassAnnotations()' gets called so frequently that we should consider caching to avoid some of the lookups.

### Uses of LRUMap in com.fasterxml.jackson.databind.type

Fields in com.fasterxml.jackson.databind.type declared as LRUMap
Modifier and Type | Field and Description
--- | ---
`protected LRUMap<Object,JavaType>` | TypeFactory.`_typeCache` Since type resolution can be expensive (specifically when resolving actual generic types), we will use small cache to avoid repetitive resolution of core types

### Uses of LRUMap in com.fasterxml.jackson.databind.util

Fields in com.fasterxml.jackson.databind.util declared as LRUMap
Modifier and Type | Field and Description
--- | ---
`protected LRUMap<ClassKey,PropertyName>` | RootNameLookup.`_rootNames` For efficient operation, let's try to minimize number of times we need to introspect root element name to use.