jdk/src/java.rmi/share/classes/java/rmi/activation/ActivationInstantiator.java

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 * accompanied this code).
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package java.rmi.activation;

import java.rmi.MarshalledObject;
import java.rmi.Remote;
import java.rmi.RemoteException;

/**
 * An <code>ActivationInstantiator</code> is responsible for creating
 * instances of "activatable" objects. A concrete subclass of
 * <code>ActivationGroup</code> implements the <code>newInstance</code>
 * method to handle creating objects within the group.
 *
 * @author      Ann Wollrath
 * @see         ActivationGroup
 * @since       1.2
 */
public interface ActivationInstantiator extends Remote {

   /**
    * The activator calls an instantiator's <code>newInstance</code>
    * method in order to recreate in that group an object with the
    * activation identifier, <code>id</code>, and descriptor,
    * <code>desc</code>. The instantiator is responsible for: <ul>
    *
    * <li> determining the class for the object using the descriptor's
    * <code>getClassName</code> method,
    *
    * <li> loading the class from the code location obtained from the
    * descriptor (using the <code>getLocation</code> method),
    *
    * <li> creating an instance of the class by invoking the special
    * "activation" constructor of the object's class that takes two
    * arguments: the object's <code>ActivationID</code>, and the
    * <code>MarshalledObject</code> containing object specific
    * initialization data, and
    *
    * <li> returning a MarshalledObject containing the stub for the
    * remote object it created.</ul>
    *
    * <p>In order for activation to be successful, one of the following requirements
    * must be met, otherwise {@link ActivationException} is thrown:
    *
    * <ul><li>The class to be activated and the special activation constructor are both public,
    * and the class resides in a package that is
    * {@linkplain Module#isExported(String,Module) exported}
    * to at least the {@code java.rmi} module; or
    *
    * <li>The class to be activated resides in a package that is
    * {@linkplain Module#isOpen(String,Module) open}
    * to at least the {@code java.rmi} module.
    * </ul>
    *
    * @param id the object's activation identifier
    * @param desc the object's descriptor
    * @return a marshalled object containing the serialized
    * representation of remote object's stub
    * @exception ActivationException if object activation fails
    * @exception RemoteException if remote call fails
    * @since 1.2
    */
    public MarshalledObject<? extends Remote> newInstance(ActivationID id,
                                                          ActivationDesc desc)
        throws ActivationException, RemoteException;
}