org.apache.river.lease

Class AbstractIDLeaseMap<K extends Lease>

java.lang.Object

java.util.AbstractMap<K,Long>

org.apache.river.lease.AbstractIDLeaseMap<K>

Type Parameters:

K -

All Implemented Interfaces:

Map<K,Long>, LeaseMap<K,Long>

Direct Known Subclasses:

LandlordLeaseMap

public abstract class AbstractIDLeaseMap<K extends Lease>
extends AbstractMap<K,Long>
implements LeaseMap<K,Long>

AbstractIDLeaseMap is intended to work around some minor design warts in the Lease interface: In the real world, when a Lease is renewed, a new Lease contract document is issued, however when an electronic Lease is renewed the Lease expiry date is changed and the record of the previous Lease is lost. Ideally the renew method would return a new Lease. Current Lease implementations rely on a Uuid to represents the lease, the expiry date is not included the equals or hashCode calculations. For this reason, two Lease objects, one expired and one valid, may be equal, this is undesirable. The Lease interface doesn't specify a contract for equals or hashCode, all Lease implementations are also mutable, previous implementations of LeaseMap used Leases as keys. AbstractIDLeaseMap uses only the ID, usually a Uuid provided by a Lease for internal map keys, if ID is not implemented then the Lease itself is used as the key. Both Lease keys and Long values are actually stored internally as values referred to by ID keys, allowing Lease implementations to either not override hashCode and equals object methods or allow implementations that more accurately model reality. This implementation is thread safe, concurrent and doesn't require external synchronization.

Author:

peter

Nested Class Summary

Nested classes/interfaces inherited from class java.util.AbstractMap

AbstractMap.SimpleEntry<K,V>, AbstractMap.SimpleImmutableEntry<K,V>

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

Map.Entry<K,V>

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	AbstractIDLeaseMap() Constructor for subclasses.

Method Summary

Modifier and Type	Method and Description
boolean	containsKey(Object key) Determines whether the ID of the key matches the ID of another key in the map.
boolean	containsValue(Object value)
Set<Map.Entry<K,Long>>	entrySet()
Long	get(Object key)
Long	put(K key, Long value) This implementation will place a new key value pair association in the map, or it will replace both the key and the value if an equivalent association currently exists in the map.
Long	remove(Object key)

Methods inherited from class java.util.AbstractMap

clear, clone, equals, hashCode, isEmpty, keySet, putAll, size, toString, values

Methods inherited from class java.lang.Object

finalize, getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface net.jini.core.lease.LeaseMap

cancelAll, canContainKey, renewAll

Methods inherited from interface java.util.Map

clear, compute, computeIfAbsent, computeIfPresent, equals, forEach, getOrDefault, hashCode, isEmpty, keySet, merge, putAll, putIfAbsent, remove, replace, replace, replaceAll, size, values

Constructor Detail

AbstractIDLeaseMap

protected AbstractIDLeaseMap()

Constructor for subclasses.

Method Detail

entrySet

public Set<Map.Entry<K,Long>> entrySet()

Specified by:

entrySet in interface Map<K extends Lease,Long>

Specified by:

entrySet in class AbstractMap<K extends Lease,Long>

containsValue

public boolean containsValue(Object value)

Specified by:

containsValue in interface Map<K extends Lease,Long>

Overrides:

containsValue in class AbstractMap<K extends Lease,Long>

containsKey

public boolean containsKey(Object key)

Determines whether the ID of the key matches the ID of another key in the map.

Specified by:

containsKey in interface Map<K extends Lease,Long>

Overrides:

containsKey in class AbstractMap<K extends Lease,Long>

Parameters:

key -

Returns:

get

public Long get(Object key)

Specified by:

get in interface Map<K extends Lease,Long>

Overrides:

get in class AbstractMap<K extends Lease,Long>

put

public Long put(K key,
                Long value)

This implementation will place a new key value pair association in the map, or it will replace both the key and the value if an equivalent association currently exists in the map.

Specified by:

put in interface Map<K extends Lease,Long>

Overrides:

put in class AbstractMap<K extends Lease,Long>

Parameters:

key -

value -

Returns:

remove

public Long remove(Object key)

Specified by:

remove in interface Map<K extends Lease,Long>

Overrides:

remove in class AbstractMap<K extends Lease,Long>