com.yahoo.bard.webservice.util

Interface Scope<S,K,V,T extends Scope<S,K,V,T>>

Type Parameters:

S - The address element type for looking up child scopes

K - The key type for the map

V - The value type for the map

T - The implementation type (used to type returns from getScope in subclasses)

All Superinterfaces:

Map<K,V>

All Known Implementing Classes:

MetricDictionary, ScopeMap

public interface Scope<S,K,V,T extends Scope<S,K,V,T>>
extends Map<K,V>

A Scope represents a tree of delegating maps.

A Scope may have child scopes which it encloses. It may have a parent scope which encloses it. Values defined in a parent scope will be available via (@link Map#get(K k)} on itself, unless the scope itself defines (and therefore overshadows) that entry.

Changes to a scope will be available to it's child scopes unless they overshadow the corresponding key.

The remove and clear operations are not supported on Scopes because parent scopes cannot be directly accessed or altered.

Nested Class Summary

Nested classes/interfaces inherited from interface java.util.Map

Map.Entry<K,V>

Method Summary

Modifier and Type	Method and Description
T	getScope(List<S> scopeKeys) Resolves a child scope.
default V	putScope(S scopeKey, K key, V value) Puts a key value pair into an immediate child scope.

Methods inherited from interface java.util.Map

clear, compute, computeIfAbsent, computeIfPresent, containsKey, containsValue, entrySet, equals, forEach, get, getOrDefault, hashCode, isEmpty, keySet, merge, put, putAll, putIfAbsent, remove, remove, replace, replace, replaceAll, size, values

Method Detail

getScope

T getScope(List<S> scopeKeys)

Resolves a child scope. The child scope should delegate to its parent scopes for value lookups.

Unless otherwise noted implementations should guarantee lazy initialization of child scopes.

Parameters:

scopeKeys - The subtree address expressed as a sequence of scopeKeys

Returns:

A scope which is a subtree of this scope.

putScope

default V putScope(S scopeKey,
                   K key,
                   V value)

Puts a key value pair into an immediate child scope.

Parameters:

scopeKey - The name of the child scope

key - The key for the value being stored

value - The value being stored

Returns:

The value displaced or shadowed DelegatingMap.put(Object, Object)