Class ActivationDesc
- java.lang.Object
-
- java.rmi.activation.ActivationDesc
- All Implemented Interfaces:
Serializable
public final class ActivationDesc extends Object implements Serializable
An activation descriptor contains the information necessary to activate an object:
- the object's group identifier,
- the object's fully-qualified class name,
- the object's code location (the location of the class), a codebase URL path,
- the object's restart "mode", and,
- a "marshalled" object that can contain object specific initialization data.
A descriptor registered with the activation system can be used to recreate/activate the object specified by the descriptor. The MarshalledObject
in the object's descriptor is passed as the second argument to the remote object's constructor for object to use during reinitialization/activation.
- Since:
- 1.2
- See Also:
-
Activatable
, Serialized Form
Constructor Summary
Constructor | Description |
---|---|
ActivationDesc(String className,
String location,
MarshalledObject<?> data) | Constructs an object descriptor for an object whose class name is |
ActivationDesc(String className,
String location,
MarshalledObject<?> data,
boolean restart) | Constructs an object descriptor for an object whose class name is |
ActivationDesc(ActivationGroupID groupID,
String className,
String location,
MarshalledObject<?> data) | Constructs an object descriptor for an object whose class name is |
ActivationDesc(ActivationGroupID groupID,
String className,
String location,
MarshalledObject<?> data,
boolean restart) | Constructs an object descriptor for an object whose class name is |
Method Summary
Modifier and Type | Method | Description |
---|---|---|
boolean | equals(Object obj) | Compares two activation descriptors for content equality. |
String | getClassName() | Returns the class name for the object specified by this descriptor. |
MarshalledObject<?> | getData() | Returns a "marshalled object" containing intialization/activation data for the object specified by this descriptor. |
ActivationGroupID | getGroupID() | Returns the group identifier for the object specified by this descriptor. |
String | getLocation() | Returns the code location for the object specified by this descriptor. |
boolean | getRestartMode() | Returns the "restart" mode of the object associated with this activation descriptor. |
int | hashCode() | Return the same hashCode for similar |
Methods declared in class java.lang.Object
clone, finalize, getClass, notify, notifyAll, toString, wait, wait, wait
Constructor Detail
ActivationDesc
public ActivationDesc(String className, String location, MarshalledObject<?> data) throws ActivationException
Constructs an object descriptor for an object whose class name is className
, that can be loaded from the code location
and whose initialization information is data
. If this form of the constructor is used, the groupID
defaults to the current id for ActivationGroup
for this VM. All objects with the same ActivationGroupID
are activated in the same VM.
Note that objects specified by a descriptor created with this constructor will only be activated on demand (by default, the restart mode is false
). If an activatable object requires restart services, use one of the ActivationDesc
constructors that takes a boolean parameter, restart
.
This constructor will throw ActivationException
if there is no current activation group for this VM. To create an ActivationGroup
use the ActivationGroup.createGroup
method.
- Parameters:
-
className
- the object's fully package qualified class name -
location
- the object's code location (from where the class is loaded) -
data
- the object's initialization (activation) data contained in marshalled form. - Throws:
-
ActivationException
- if the current group is nonexistent -
UnsupportedOperationException
- if and only if activation is not supported by this implementation - Since:
- 1.2
ActivationDesc
public ActivationDesc(String className, String location, MarshalledObject<?> data, boolean restart) throws ActivationException
Constructs an object descriptor for an object whose class name is className
, that can be loaded from the code location
and whose initialization information is data
. If this form of the constructor is used, the groupID
defaults to the current id for ActivationGroup
for this VM. All objects with the same ActivationGroupID
are activated in the same VM.
This constructor will throw ActivationException
if there is no current activation group for this VM. To create an ActivationGroup
use the ActivationGroup.createGroup
method.
- Parameters:
-
className
- the object's fully package qualified class name -
location
- the object's code location (from where the class is loaded) -
data
- the object's initialization (activation) data contained in marshalled form. -
restart
- if true, the object is restarted (reactivated) when either the activator is restarted or the object's activation group is restarted after an unexpected crash; if false, the object is only activated on demand. Specifyingrestart
to betrue
does not force an initial immediate activation of a newly registered object; initial activation is lazy. - Throws:
-
ActivationException
- if the current group is nonexistent -
UnsupportedOperationException
- if and only if activation is not supported by this implementation - Since:
- 1.2
ActivationDesc
public ActivationDesc(ActivationGroupID groupID, String className, String location, MarshalledObject<?> data)
Constructs an object descriptor for an object whose class name is className
that can be loaded from the code location
and whose initialization information is data
. All objects with the same groupID
are activated in the same Java VM.
Note that objects specified by a descriptor created with this constructor will only be activated on demand (by default, the restart mode is false
). If an activatable object requires restart services, use one of the ActivationDesc
constructors that takes a boolean parameter, restart
.
- Parameters:
-
groupID
- the group's identifier (obtained from registeringActivationSystem.registerGroup
method). The group indicates the VM in which the object should be activated. -
className
- the object's fully package-qualified class name -
location
- the object's code location (from where the class is loaded) -
data
- the object's initialization (activation) data contained in marshalled form. - Throws:
-
IllegalArgumentException
- ifgroupID
is null -
UnsupportedOperationException
- if and only if activation is not supported by this implementation - Since:
- 1.2
ActivationDesc
public ActivationDesc(ActivationGroupID groupID, String className, String location, MarshalledObject<?> data, boolean restart)
Constructs an object descriptor for an object whose class name is className
that can be loaded from the code location
and whose initialization information is data
. All objects with the same groupID
are activated in the same Java VM.
- Parameters:
-
groupID
- the group's identifier (obtained from registeringActivationSystem.registerGroup
method). The group indicates the VM in which the object should be activated. -
className
- the object's fully package-qualified class name -
location
- the object's code location (from where the class is loaded) -
data
- the object's initialization (activation) data contained in marshalled form. -
restart
- if true, the object is restarted (reactivated) when either the activator is restarted or the object's activation group is restarted after an unexpected crash; if false, the object is only activated on demand. Specifyingrestart
to betrue
does not force an initial immediate activation of a newly registered object; initial activation is lazy. - Throws:
-
IllegalArgumentException
- ifgroupID
is null -
UnsupportedOperationException
- if and only if activation is not supported by this implementation - Since:
- 1.2
Method Detail
getGroupID
public ActivationGroupID getGroupID()
Returns the group identifier for the object specified by this descriptor. A group provides a way to aggregate objects into a single Java virtual machine. RMI creates/activates objects with the same groupID
in the same virtual machine.
- Returns:
- the group identifier
- Since:
- 1.2
getClassName
public String getClassName()
Returns the class name for the object specified by this descriptor.
- Returns:
- the class name
- Since:
- 1.2
getLocation
public String getLocation()
Returns the code location for the object specified by this descriptor.
- Returns:
- the code location
- Since:
- 1.2
getData
public MarshalledObject<?> getData()
Returns a "marshalled object" containing intialization/activation data for the object specified by this descriptor.
- Returns:
- the object specific "initialization" data
- Since:
- 1.2
getRestartMode
public boolean getRestartMode()
Returns the "restart" mode of the object associated with this activation descriptor.
- Returns:
- true if the activatable object associated with this activation descriptor is restarted via the activation daemon when either the daemon comes up or the object's group is restarted after an unexpected crash; otherwise it returns false, meaning that the object is only activated on demand via a method call. Note that if the restart mode is
true
, the activator does not force an initial immediate activation of a newly registered object; initial activation is lazy. - Since:
- 1.2
equals
public boolean equals(Object obj)
Compares two activation descriptors for content equality.
- Overrides:
-
equals
in classObject
- Parameters:
-
obj
- the Object to compare with - Returns:
- true if these Objects are equal; false otherwise.
- Since:
- 1.2
- See Also:
Hashtable
hashCode
public int hashCode()
Return the same hashCode for similar ActivationDesc
s.