public final class Bind extends Object
Modifier and Type | Class and Description |
---|---|
static interface |
Bind.MapListener<K,V>
Listener called when `Map` is modified.
|
static interface |
Bind.MapWithModificationListener<K,V>
Primary Maps must provide notifications when it is modified.
|
Modifier and Type | Method and Description |
---|---|
static <K,V,C> void |
histogram(Bind.MapWithModificationListener<K,V> primary,
ConcurrentMap<C,Long> histogram,
Fun.Function2<C,K,V> entryToCategory)
Binds Secondary Map so it it creates [histogram](http://en.wikipedia.org/wiki/Histogram) from
data in Primary Map.
|
static <K,V> void |
mapInverse(Bind.MapWithModificationListener<K,V> primary,
Map<V,K> inverse)
Binds Secondary Set so it contains inverse mapping to Primary Map: Primary Value will become Secondary Key.
|
static <K,V> void |
mapInverse(Bind.MapWithModificationListener<K,V> primary,
Set<Fun.Tuple2<V,K>> inverse)
Binds Secondary Set so it contains inverse mapping to Primary Map: Primary Value will become Secondary Key.
|
static <K,V,K2> void |
secondaryKey(Bind.MapWithModificationListener<K,V> map,
Map<K2,K> secondary,
Fun.Function2<K2,K,V> fun)
Binds Secondary Set so it contains Secondary Key (Index).
|
static <K,V,K2> void |
secondaryKey(Bind.MapWithModificationListener<K,V> map,
Set<Fun.Tuple2<K2,K>> secondary,
Fun.Function2<K2,K,V> fun)
Binds Secondary Set so it contains Secondary Key (Index).
|
static <K,V,K2> void |
secondaryKeys(Bind.MapWithModificationListener<K,V> map,
Set<Fun.Tuple2<K2,K>> secondary,
Fun.Function2<K2[],K,V> fun)
Binds Secondary Set so it contains Secondary Key (Index).
|
static <K,V,V2> void |
secondaryValue(Bind.MapWithModificationListener<K,V> map,
Map<K,V2> secondary,
Fun.Function2<V2,K,V> fun)
Binds Secondary Map so that it contains Key from Primary Map and custom Value.
|
static <K,V,V2> void |
secondaryValues(Bind.MapWithModificationListener<K,V> map,
Set<Fun.Tuple2<K,V2>> secondary,
Fun.Function2<V2[],K,V> fun)
Binds Secondary Map so that it contains Key from Primary Map and custom Value.
|
static <K,V> void |
size(Bind.MapWithModificationListener<K,V> map,
Atomic.Long sizeCounter)
Binds
Atomic.Long to Primary Map so the Atomic.Long contains size of Map. |
public static <K,V> void size(Bind.MapWithModificationListener<K,V> map, Atomic.Long sizeCounter)
Atomic.Long
to Primary Map so the Atomic.Long contains size of Map.
`Atomic.Long` is incremented on each insert and decremented on each entry removal.
MapDB collections usually do not keep their size, but require complete traversal to count items.
If `Atomic.Long` has zero value, it will be updated with value from `map.size()` and than
bind to map.
NOTE: Binding just installs Modification Listener on primary collection. Binding itself is not persistent
and has to be restored after primary collection is loaded. Data contained in secondary collection are persistent.
NOTE: BTreeMap
and HTreeMap
already supports this directly as optional parameter named `counter`.
In that case all calls to `Map.size()` are forwarded to underlying counter. Check parameters at
DB.createHashMap(String)
and
DB.createTreeMap(String)
map
- primary map whose size needs to be trackedsizeCounter
- number updated when Map Entry is added or removed.public static <K,V,V2> void secondaryValue(Bind.MapWithModificationListener<K,V> map, Map<K,V2> secondary, Fun.Function2<V2,K,V> fun)
map
- Primary Mapsecondary
- Secondary Map with customfun
- function which calculates secondary value from primary key and valuepublic static <K,V,V2> void secondaryValues(Bind.MapWithModificationListener<K,V> map, Set<Fun.Tuple2<K,V2>> secondary, Fun.Function2<V2[],K,V> fun)
map
- Primary Mapsecondary
- Secondary Map with customfun
- function which calculates secondary values from primary key and valuepublic static <K,V,K2> void secondaryKey(Bind.MapWithModificationListener<K,V> map, Set<Fun.Tuple2<K2,K>> secondary, Fun.Function2<K2,K,V> fun)
Fun.filter(java.util.NavigableSet, Object)
If Secondary Set is empty its content will be recreated from Primary Map.
This binding is not persistent. You need to restore it every time store is reopened.
NOTE: Binding just installs Modification Listener on primary collection. Binding itself is not persistent
and has to be restored after primary collection is loaded. Data contained in secondary collection are persistent.
Type params:
* `map
- primary mapsecondary
- secondary setfun
- function which calculates Secondary Key from Primary Key and Valuepublic static <K,V,K2> void secondaryKey(Bind.MapWithModificationListener<K,V> map, Map<K2,K> secondary, Fun.Function2<K2,K,V> fun)
map
- primary mapsecondary
- secondary setfun
- function which calculates Secondary Key from Primary Key and Valuepublic static <K,V,K2> void secondaryKeys(Bind.MapWithModificationListener<K,V> map, Set<Fun.Tuple2<K2,K>> secondary, Fun.Function2<K2[],K,V> fun)
Fun.filter(java.util.NavigableSet, Object)
}
If Secondary Set is empty its content will be recreated from Primary Map.
NOTE: Binding just installs Modification Listener on primary collection. Binding itself is not persistent
and has to be restored after primary collection is loaded. Data contained in secondary collection are persistent.
Type params:
* `map
- primary mapsecondary
- secondary setfun
- function which calculates Secondary Keys from Primary Key and Valuepublic static <K,V> void mapInverse(Bind.MapWithModificationListener<K,V> primary, Set<Fun.Tuple2<V,K>> inverse)
Fun.filter(java.util.NavigableSet, Object)
If Secondary Set is empty its content will be recreated from Primary Map.
NOTE: Binding just installs Modification Listener on primary collection. Binding itself is not persistent
and has to be restored after primary collection is loaded. Data contained in secondary collection are persistent.
Type params:
* `primary
- Primary Map for which inverse mapping will be createdinverse
- Secondary Set which will contain inverse mappingpublic static <K,V> void mapInverse(Bind.MapWithModificationListener<K,V> primary, Map<V,K> inverse)
primary
- Primary Map for which inverse mapping will be createdinverse
- Secondary Set which will contain inverse mappingpublic static <K,V,C> void histogram(Bind.MapWithModificationListener<K,V> primary, ConcurrentMap<C,Long> histogram, Fun.Function2<C,K,V> entryToCategory)
primary
- Primary Map to create histogram forhistogram
- Secondary Map to create histogram for, key is Category, value is number of items in categoryentryToCategory
- returns Category in which entry from Primary Map belongs to.Copyright © 2016. All rights reserved.