inet.ipaddr

Class IPAddressNetwork.HostIdentifierStringCache<T extends HostIdentifierString>

java.lang.Object

inet.ipaddr.IPAddressNetwork.HostIdentifierStringCache<T>

Type Parameters:

T - the type to be cached, typically either IPAddressString or HostName

All Implemented Interfaces:

java.io.Serializable

Direct Known Subclasses:

IPAddressNetwork.HostNameCache, IPAddressNetwork.IPAddressStringCache

Enclosing class:

IPAddressNetwork

public abstract static class IPAddressNetwork.HostIdentifierStringCache<T extends HostIdentifierString>
extends java.lang.Object
implements java.io.Serializable

Choose a map of your choice to implement a cache of addresses and/or host names.

For long-running programs or servers that handle many addresses, the benefits of using a cache are that

• the lookup can provide the same objects for different strings that identify the same host name or address
• parsing and resolving repeated instances of the same address or host string is minimized. Both IPAddressString and HostName cache their parsed and resolved addresses.
• other functionality is optimized through caching, since Host Name, IPAddressString, and IPAddress also caches objects such as generated strings. With cached objects, switching between host names, address strings and numeric addresses is constant time.

You choose the map of your choice to be the backing map for the cache. For example, for thread-safe access to the cache, ConcurrentHashMap is a good choice. For maps of bounded size, LinkedHashMap provides the removeEldestEntry method to override to implement LRU or other eviction mechanisms.

See Also:

Serialized Form

Constructor Summary

Constructors

Constructor and Description
HostIdentifierStringCache(java.util.Map<java.lang.String,T> backingMap)

Method Summary

Modifier and Type	Method and Description
boolean	contains(T value) Returns whether the given instance is in the cache.
T	get(byte[] bytes)
T	get(IPAddress.IPVersion version, Address.SegmentValueProvider lowerValueProvider, Address.SegmentValueProvider upperValueProvider, java.lang.Integer prefixLength)
T	get(IPAddress.IPVersion version, Address.SegmentValueProvider lowerValueProvider, Address.SegmentValueProvider upperValueProvider, java.lang.Integer prefixLength, java.lang.CharSequence zone)
T	get(java.lang.String key) Gets the object for the given key.
java.util.Map<java.lang.String,T>	getBackingMap()
static Address.SegmentValueProvider	getValueProvider(byte[] bytes)

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

HostIdentifierStringCache

public HostIdentifierStringCache(java.util.Map<java.lang.String,T> backingMap)

Method Detail

getBackingMap

public java.util.Map<java.lang.String,T> getBackingMap()

contains

public boolean contains(T value)

Returns whether the given instance is in the cache.

Parameters:

value -

Returns:

whether the given instance of T is in the cache

get

public T get(java.lang.String key)

Gets the object for the given key. If the object does not exist yet then it is created and added to the cache.

Parameters:

key -

Returns:

the object for the given key

Throws:

HostIdentifierException - if the key does not correspond to an instance of type T

getValueProvider

public static Address.SegmentValueProvider getValueProvider(byte[] bytes)

get

public T get(byte[] bytes)

get

public T get(IPAddress.IPVersion version,
             Address.SegmentValueProvider lowerValueProvider,
             Address.SegmentValueProvider upperValueProvider,
             java.lang.Integer prefixLength)

get

public T get(IPAddress.IPVersion version,
             Address.SegmentValueProvider lowerValueProvider,
             Address.SegmentValueProvider upperValueProvider,
             java.lang.Integer prefixLength,
             java.lang.CharSequence zone)