com.netflix.spectator.atlas.impl

Class QueryIndex<T>

java.lang.Object

com.netflix.spectator.atlas.impl.QueryIndex<T>

public final class QueryIndex<T>
extends Object

Index that to efficiently match an Id against a set of queries that are known in advance. The index is thread safe for queries. Updates to the index should be done from a single thread at a time.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static interface	QueryIndex.CacheSupplier<V> Supplier to create a new instance of a cache used for other checks.
static class	QueryIndex.DefaultCacheSupplier<V> Default supplier based on a simple LFU cache.

Method Summary

Modifier and Type	Method and Description
QueryIndex<T>	add(Query query, T value) Add a value that should match for the specified query.
List<T>	findMatches(Function<String,String> tags) Find all values where the corresponding queries match the specified tags.
List<T>	findMatches(com.netflix.spectator.api.Id id) Find all values where the corresponding queries match the specified id.
void	forEachMatch(Function<String,String> tags, Consumer<T> consumer) Invoke the consumer for all values where the corresponding queries match the specified tags.
void	forEachMatch(com.netflix.spectator.api.Id id, Consumer<T> consumer) Invoke the consumer for all values where the corresponding queries match the specified id.
boolean	isEmpty() Returns true if this index is empty and wouldn't match any ids.
static <V> QueryIndex<V>	newInstance(QueryIndex.CacheSupplier<V> cacheSupplier) Return a new instance of an index that is empty.
static <V> QueryIndex<V>	newInstance(com.netflix.spectator.api.Registry registry) Return a new instance of an index that is empty.
boolean	remove(Query query, T value) Remove the specified value associated with a specific query from the index.
String	toString()

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Method Detail

newInstance

public static <V> QueryIndex<V> newInstance(com.netflix.spectator.api.Registry registry)

Return a new instance of an index that is empty. The default caching behavior will be used.

newInstance

public static <V> QueryIndex<V> newInstance(QueryIndex.CacheSupplier<V> cacheSupplier)

Return a new instance of an index that is empty. The caches will be used to cache the results of regex or other checks to try and avoid scans with repeated string values across many ids.

add

public QueryIndex<T> add(Query query,
                         T value)

Add a value that should match for the specified query.

Parameters:

query - Query that corresponds to the value.

value - Value to return for ids that match the query.

Returns:

This index so it can be used in a fluent manner.

remove

public boolean remove(Query query,
                      T value)

Remove the specified value associated with a specific query from the index. Returns true if a value was successfully removed.

isEmpty

public boolean isEmpty()

Returns true if this index is empty and wouldn't match any ids.

findMatches

public List<T> findMatches(com.netflix.spectator.api.Id id)

Find all values where the corresponding queries match the specified id.

Parameters:

id - Id to check against the queries.

Returns:

List of all matching values for the id.

forEachMatch

public void forEachMatch(com.netflix.spectator.api.Id id,
                         Consumer<T> consumer)

Invoke the consumer for all values where the corresponding queries match the specified id.

Parameters:

id - Id to check against the queries.

consumer - Function to invoke for values associated with a query that matches the id.

findMatches

public List<T> findMatches(Function<String,String> tags)

Find all values where the corresponding queries match the specified tags. This can be used if the tags are not already structured as a spectator Id.

Parameters:

tags - Function to look up the value for a given tag key. The function should return null if there is no value for the key.

Returns:

List of all matching values for the id.

forEachMatch

public void forEachMatch(Function<String,String> tags,
                         Consumer<T> consumer)

Invoke the consumer for all values where the corresponding queries match the specified tags. This can be used if the tags are not already structured as a spectator Id.

Parameters:

tags - Function to look up the value for a given tag key. The function should return null if there is no value for the key.

consumer - Function to invoke for values associated with a query that matches the id.

toString

public String toString()

Overrides:

toString in class Object