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	/*
	* Copyright (c) 1997, 2013, Oracle and/or its affiliates. All rights reserved.
	* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
	*
	* This code is free software; you can redistribute it and/or modify it
	* under the terms of the GNU General Public License version 2 only, as
	* published by the Free Software Foundation. Oracle designates this
	* particular file as subject to the "Classpath" exception as provided
	* by Oracle in the LICENSE file that accompanied this code.
	*
	* This code is distributed in the hope that it will be useful, but WITHOUT
	* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
	* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
	* version 2 for more details (a copy is included in the LICENSE file that
	* accompanied this code).
	*
	* You should have received a copy of the GNU General Public License version
	* 2 along with this work; if not, write to the Free Software Foundation,
	* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
	*
	* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
	* or visit www.oracle.com if you need additional information or have any
	* questions.
	*/

	package java.rmi.activation;

	import java.io.Serializable;
	import java.rmi.MarshalledObject;

	/**
	* An activation descriptor contains the information necessary to
	* activate an object: <ul>
	* <li> the object's group identifier,
	* <li> the object's fully-qualified class name,
	* <li> the object's code location (the location of the class), a codebase URL
	* path,
	* <li> the object's restart "mode", and,
	* <li> a "marshalled" object that can contain object specific
	* initialization data. </ul>
	*
	* <p>A descriptor registered with the activation system can be used to
	* recreate/activate the object specified by the descriptor. The
	* <code>MarshalledObject</code> in the object's descriptor is passed
	* as the second argument to the remote object's constructor for
	* object to use during reinitialization/activation.
	*
	* @author Ann Wollrath
	* @since 1.2
	* @see java.rmi.activation.Activatable
	*/
	public final class ActivationDesc implements Serializable {

	/**
	* @serial the group's identifier
	*/
	private ActivationGroupID groupID;

	/**
	* @serial the object's class name
	*/
	private String className;

	/**
	* @serial the object's code location
	*/
	private String location;

	/**
	* @serial the object's initialization data
	*/
	private MarshalledObject<?> data;

	/**
	* @serial indicates whether the object should be restarted
	*/
	private boolean restart;

	/** indicate compatibility with the Java 2 SDK v1.2 version of class */
	private static final long serialVersionUID = 7455834104417690957L;

	/**
	* Constructs an object descriptor for an object whose class name
	* is <code>className</code>, that can be loaded from the
	* code <code>location</code> and whose initialization
	* information is <code>data</code>. If this form of the constructor
	* is used, the <code>groupID</code> defaults to the current id for
	* <code>ActivationGroup</code> for this VM. All objects with the
	* same <code>ActivationGroupID</code> are activated in the same VM.
	*
	* <p>Note that objects specified by a descriptor created with this
	* constructor will only be activated on demand (by default, the restart
	* mode is <code>false</code>). If an activatable object requires restart
	* services, use one of the <code>ActivationDesc</code> constructors that
	* takes a boolean parameter, <code>restart</code>.
	*
	* <p> This constructor will throw <code>ActivationException</code> if
	* there is no current activation group for this VM. To create an
	* <code>ActivationGroup</code> use the
	* <code>ActivationGroup.createGroup</code> method.
	*
	* @param className the object's fully package qualified class name
	* @param location the object's code location (from where the class is
	* loaded)
	* @param data the object's initialization (activation) data contained
	* in marshalled form.
	* @exception ActivationException if the current group is nonexistent
	* @exception UnsupportedOperationException if and only if activation is
	* not supported by this implementation
	* @since 1.2
	*/
	public ActivationDesc(String className,
	String location,
	MarshalledObject<?> data)
	throws ActivationException
	{
	this(ActivationGroup.internalCurrentGroupID(),
	className, location, data, false);
	}

	/**
	* Constructs an object descriptor for an object whose class name
	* is <code>className</code>, that can be loaded from the
	* code <code>location</code> and whose initialization
	* information is <code>data</code>. If this form of the constructor
	* is used, the <code>groupID</code> defaults to the current id for
	* <code>ActivationGroup</code> for this VM. All objects with the
	* same <code>ActivationGroupID</code> are activated in the same VM.
	*
	* <p>This constructor will throw <code>ActivationException</code> if
	* there is no current activation group for this VM. To create an
	* <code>ActivationGroup</code> use the
	* <code>ActivationGroup.createGroup</code> method.
	*
	* @param className the object's fully package qualified class name
	* @param location the object's code location (from where the class is
	* loaded)
	* @param data the object's initialization (activation) data contained
	* in marshalled form.
	* @param 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. Specifying <code>restart</code> to be
	* <code>true</code> does not force an initial immediate activation of
	* a newly registered object; initial activation is lazy.
	* @exception ActivationException if the current group is nonexistent
	* @exception UnsupportedOperationException if and only if activation is
	* not supported by this implementation
	* @since 1.2
	*/
	public ActivationDesc(String className,
	String location,
	MarshalledObject<?> data,
	boolean restart)
	throws ActivationException
	{
	this(ActivationGroup.internalCurrentGroupID(),
	className, location, data, restart);
	}

	/**
	* Constructs an object descriptor for an object whose class name
	* is <code>className</code> that can be loaded from the
	* code <code>location</code> and whose initialization
	* information is <code>data</code>. All objects with the same
	* <code>groupID</code> are activated in the same Java VM.
	*
	* <p>Note that objects specified by a descriptor created with this
	* constructor will only be activated on demand (by default, the restart
	* mode is <code>false</code>). If an activatable object requires restart
	* services, use one of the <code>ActivationDesc</code> constructors that
	* takes a boolean parameter, <code>restart</code>.
	*
	* @param groupID the group's identifier (obtained from registering
	* <code>ActivationSystem.registerGroup</code> method). The group
	* indicates the VM in which the object should be activated.
	* @param className the object's fully package-qualified class name
	* @param location the object's code location (from where the class is
	* loaded)
	* @param data the object's initialization (activation) data contained
	* in marshalled form.
	* @exception IllegalArgumentException if <code>groupID</code> is null
	* @exception UnsupportedOperationException if and only if activation is
	* not supported by this implementation
	* @since 1.2
	*/
	public ActivationDesc(ActivationGroupID groupID,
	String className,
	String location,
	MarshalledObject<?> data)
	{
	this(groupID, className, location, data, false);
	}

	/**
	* Constructs an object descriptor for an object whose class name
	* is <code>className</code> that can be loaded from the
	* code <code>location</code> and whose initialization
	* information is <code>data</code>. All objects with the same
	* <code>groupID</code> are activated in the same Java VM.
	*
	* @param groupID the group's identifier (obtained from registering
	* <code>ActivationSystem.registerGroup</code> method). The group
	* indicates the VM in which the object should be activated.
	* @param className the object's fully package-qualified class name
	* @param location the object's code location (from where the class is
	* loaded)
	* @param data the object's initialization (activation) data contained
	* in marshalled form.
	* @param 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. Specifying <code>restart</code> to be
	* <code>true</code> does not force an initial immediate activation of
	* a newly registered object; initial activation is lazy.
	* @exception IllegalArgumentException if <code>groupID</code> is null
	* @exception UnsupportedOperationException if and only if activation is
	* not supported by this implementation
	* @since 1.2
	*/
	public ActivationDesc(ActivationGroupID groupID,
	String className,
	String location,
	MarshalledObject<?> data,
	boolean restart)
	{
	if (groupID == null)
	throw new IllegalArgumentException("groupID can't be null");
	this.groupID = groupID;
	this.className = className;
	this.location = location;
	this.data = data;
	this.restart = restart;
	}

	/**
	* 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 <code>groupID</code> in the same virtual machine.
	*
	* @return the group identifier
	* @since 1.2
	*/
	public ActivationGroupID getGroupID() {
	return groupID;
	}

	/**
	* Returns the class name for the object specified by this
	* descriptor.
	* @return the class name
	* @since 1.2
	*/
	public String getClassName() {
	return className;
	}

	/**
	* Returns the code location for the object specified by
	* this descriptor.
	* @return the code location
	* @since 1.2
	*/
	public String getLocation() {
	return location;
	}

	/**
	* Returns a "marshalled object" containing intialization/activation
	* data for the object specified by this descriptor.
	* @return the object specific "initialization" data
	* @since 1.2
	*/
	public MarshalledObject<?> getData() {
	return data;
	}

	/**
	* Returns the "restart" mode of the object associated with
	* this activation descriptor.
	*
	* @return 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 <code>true</code>, the
	* activator does not force an initial immediate activation of
	* a newly registered object; initial activation is lazy.
	* @since 1.2
	*/
	public boolean getRestartMode() {
	return restart;
	}

	/**
	* Compares two activation descriptors for content equality.
	*
	* @param obj the Object to compare with
	* @return true if these Objects are equal; false otherwise.
	* @see java.util.Hashtable
	* @since 1.2
	*/
	public boolean equals(Object obj) {

	if (obj instanceof ActivationDesc) {
	ActivationDesc desc = (ActivationDesc) obj;
	return
	((groupID == null ? desc.groupID == null :
	groupID.equals(desc.groupID)) &&
	(className == null ? desc.className == null :
	className.equals(desc.className)) &&
	(location == null ? desc.location == null:
	location.equals(desc.location)) &&
	(data == null ? desc.data == null :
	data.equals(desc.data)) &&
	(restart == desc.restart));

	} else {
	return false;
	}
	}

	/**
	* Return the same hashCode for similar <code>ActivationDesc</code>s.
	* @return an integer
	* @see java.util.Hashtable
	*/
	public int hashCode() {
	return ((location == null
	? 0
	: location.hashCode() << 24) ^
	(groupID == null
	? 0
	: groupID.hashCode() << 16) ^
	(className == null
	? 0
	: className.hashCode() << 9) ^
	(data == null
	? 0
	: data.hashCode() << 1) ^
	(restart
	? 1
	: 0));
	}
	}

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