This class represents a reference to an object that is found outside of
the naming/directory system.
Reference provides a way of recording address information about
objects which themselves are not directly bound to the naming/directory system.
A Reference consists of an ordered list of addresses and class information
about the object being referenced.
Each address in the list identifies a communications endpoint
for the same conceptual object. The "communications endpoint"
is information that indicates how to contact the object. It could
be, for example, a network address, a location in memory on the
local machine, another process on the same machine, etc.
The order of the addresses in the list may be of significance
to object factories that interpret the reference.
Multiple addresses may arise for
various reasons, such as replication or the object offering interfaces
over more than one communication mechanism. The addresses are indexed
starting with zero.
A Reference also contains information to assist in creating an instance
of the object to which this Reference refers. It contains the class name
of that object, and the class name and location of the factory to be used
to create the object.
The class factory location is a space-separated list of URLs representing
the class path used to load the factory. When the factory class (or
any class or resource upon which it depends) needs to be loaded,
each URL is used (in order) to attempt to load the class.
A Reference instance is not synchronized against concurrent access by multiple
threads. Threads that need to access a single Reference concurrently should
synchronize amongst themselves and provide the necessary locking.
className
Contains the fully-qualified name of the class of the object to which
this Reference refers.
Constructor Summary
Reference(String className)
Constructs a new reference for an object with class name 'className'.
Reference(String className,
RefAddr addr)
Constructs a new reference for an object with class name 'className' and
an address.
Reference(String className,
RefAddr addr,
String factory,
String factoryLocation)
Constructs a new reference for an object with class name 'className',
the class name and location of the object's factory, and the address for
the object.
Reference(String className,
String factory,
String factoryLocation)
Constructs a new reference for an object with class name 'className',
and the class name and location of the object's factory.
Method Summary
void
add(int posn,
RefAddr addr)
Adds an address to the list of addresses at index posn.
void
add(RefAddr addr)
Adds an address to the end of the list of addresses.
void
clear()
Deletes all addresses from this reference.
Constructs a new reference for an object with class name 'className'.
Class factory and class factory location are set to null.
The newly created reference contains zero addresses.
Parameters:
className - The non-null class name of the object to which
this reference refers.
Constructs a new reference for an object with class name 'className',
the class name and location of the object's factory, and the address for
the object.
Parameters:
className - The non-null class name of the object to
which this reference refers.
factory - The possibly null class name of the object's factory.
factoryLocation - The possibly null location from which
to load the factory (e.g. URL)
Retrieves the location of the factory of the object
to which this reference refers.
If it is a codebase, then it is an ordered list of URLs,
separated by spaces, listing locations from where the factory
class definition should be loaded.
Returns:
The possibly null string containing the
location for loading in the factory's class.
Retrieves an enumeration of the addresses in this reference.
When addresses are added, changed or removed from this reference,
its effects on this enumeration are undefined.
Returns:
An non-null enumeration of the addresses
(RefAddr) in this reference.
If this reference has zero addresses, an enumeration with
zero elements is returned.
size
public int size()
Retrieves the number of addresses in this reference.
Returns:
The nonnegative number of addresses in this reference.
Deletes the address at index posn from the list of addresses.
All addresses at index greater than posn are shifted down
the list by one (towards index 0).
Determines whether obj is a reference with the same addresses
(in same order) as this reference.
The addresses are checked using RefAddr.equals().
In addition to having the same addresses, the Reference also needs to
have the same class name as this reference.
The class factory and class factory location are not checked.
If obj is null or not an instance of Reference, null is returned.
Generates the string representation of this reference.
The string consists of the class name to which this reference refers,
and the string representation of each of its addresses.
This representation is intended for display only and not to be parsed.
Makes a copy of this reference using its class name
list of addresses, class factory name and class factory location.
Changes to the newly created copy does not affect this Reference
and vice versa.
CloneNotSupportedException - if the object's class does not
support the Cloneable interface. Subclasses
that override the clone method can also
throw this exception to indicate that an instance cannot
be cloned.
Submit a bug or feature For further API reference and developer documentation, see Java 2 SDK SE Developer Documentation. That documentation contains more detailed, developer-targeted descriptions, with conceptual overviews, definitions of terms, workarounds, and working code examples.
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