nameservice.java

java1.6众多例子参考

/*
 * @(#)NameService.java	1.11 05/11/17
 *
 * Copyright 2006 Sun Microsystems, Inc. All rights reserved.
 * SUN PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 */
/*
 * @(#)NameService.java 1.3 00/04/06
 *
 * Copyright 1993-1997 Sun Microsystems, Inc. 901 San Antonio Road,
 * Palo Alto, California, 94303, U.S.A.  All Rights Reserved.
 *
 * This software is the confidential and proprietary information of Sun
 * Microsystems, Inc. ("Confidential Information").  You shall not
 * disclose such Confidential Information and shall use it only in
 * accordance with the terms of the license agreement you entered into
 * with Sun.
 *
 * CopyrightVersion 1.2
 *
 */

package com.sun.corba.se.impl.naming.pcosnaming;

import java.io.File;
import java.util.Properties;

import org.omg.CORBA.Policy;
import org.omg.PortableServer.POA;
import org.omg.PortableServer.LifespanPolicyValue;
import org.omg.PortableServer.RequestProcessingPolicyValue;
import org.omg.PortableServer.IdAssignmentPolicyValue;
import org.omg.PortableServer.ServantRetentionPolicyValue;
import org.omg.CosNaming.NamingContext;
import org.omg.CosNaming.NamingContextHelper;
import org.omg.PortableServer.*;

import com.sun.corba.se.spi.orb.ORB ;

import com.sun.corba.se.impl.orbutil.ORBConstants ;

/**
 * @version     1.3, 00/04/06
 * @author      Hemanth Puttaswamy
 * @since       JDK1.2
 */

public class NameService
{
    private NamingContext rootContext = null;
    private POA nsPOA = null;
    private ServantManagerImpl contextMgr;
    private ORB theorb;

    /**
     * Create NameService which starts the Root Naming Context in Persistent CosNaming
     * @param orb an ORB object.
     * @param logDir a File
     * @exception java.lang.Exception a Java exception.
     */
    public NameService(ORB orb, File logDir)
	throws Exception
    {
	theorb = orb;

	// Moved this to the creation of the ORB that is passed into this
	// constructor.
	// 
	// This is required for creating Persistent Servants under this ORB
	// Right now the Persistent NameService and ORBD are launched together
	// Find out a better way of doing this, Since ORBD is an important
	// process which should not be killed because of some external process
	// orb.setPersistentServerId( (int) 1000 );

	// get and activate the root naming POA
	POA rootPOA = (POA)orb.resolve_initial_references(
	    ORBConstants.ROOT_POA_NAME ) ;
	rootPOA.the_POAManager().activate();

	// create a new POA for persistent Naming Contexts
	// With Non-Retain policy, So that every time Servant Manager
	// will be contacted when the reference is made for the context
	// The id assignment is made by the NameServer, The Naming Context
	// id's will be in the format NC<Index>
	int i=0;
	Policy[] poaPolicy = new Policy[4];
	poaPolicy[i++] = rootPOA.create_lifespan_policy(
			 LifespanPolicyValue.PERSISTENT);
	poaPolicy[i++] = rootPOA.create_request_processing_policy(
			 RequestProcessingPolicyValue.USE_SERVANT_MANAGER);
	poaPolicy[i++] = rootPOA.create_id_assignment_policy(
		         IdAssignmentPolicyValue.USER_ID);
        poaPolicy[i++] = rootPOA.create_servant_retention_policy(
			 ServantRetentionPolicyValue.NON_RETAIN);


	nsPOA = rootPOA.create_POA("NameService", null, poaPolicy);
	nsPOA.the_POAManager().activate( );

	// create and set the servant manager
	contextMgr = new 
	    ServantManagerImpl(orb, logDir, this );

	// The RootObject key will be NC0
	String rootKey = contextMgr.getRootObjectKey( ); 
	// initialize the root Naming Context
	NamingContextImpl nc = 
		new NamingContextImpl( orb, rootKey, this, contextMgr );
	nc = contextMgr.addContext( rootKey, nc );
	nc.setServantManagerImpl( contextMgr );
	nc.setORB( orb );
	nc.setRootNameService( this );

	nsPOA.set_servant_manager(contextMgr);
	rootContext = NamingContextHelper.narrow(
	nsPOA.create_reference_with_id( rootKey.getBytes( ), 
	NamingContextHelper.id( ) ) );
    }

    /**
     * This method returns the Root Naming Context
     */
    public NamingContext initialNamingContext()
    {
	return rootContext;
    }

    /**
     * This method returns nsPOA which is the only POA that we use for 
     * Persistent Naming Contexts.
     */
    POA getNSPOA( ) {
        return nsPOA;
    }


    /**
     * This method  creates a NewContext, This will internally invoked from
     * NamingContextImpl. It is not a public API. NewContext is in this class
     * because a Persiten reference has to be created with Persistent NameService
     * POA.
     */
    public NamingContext NewContext( ) throws org.omg.CORBA.SystemException 
    {
	try
	{
		// Get the new Naming Context Key from 
		// the ServantManager
		String newKey = 
		contextMgr.getNewObjectKey( );
		// Create the new Naming context and create the Persistent
		// reference
		NamingContextImpl theContext = 
		new NamingContextImpl( theorb, newKey,
		    this, contextMgr );
		NamingContextImpl tempContext = contextMgr.addContext( newKey,
						 theContext );
		if( tempContext != null )
		{
			theContext = tempContext;
		}
		// If the context is read from the File, The following three entries
		// will be null. So a fresh setup may be required.
		theContext.setServantManagerImpl( contextMgr );
		theContext.setORB( theorb );
		theContext.setRootNameService( this );
	        NamingContext theNewContext = 
		NamingContextHelper.narrow(
	 	nsPOA.create_reference_with_id( newKey.getBytes( ), 
	        NamingContextHelper.id( )) );
		return theNewContext;
	}
	catch( org.omg.CORBA.SystemException e )
	{
		throw e;
	}
	catch( java.lang.Exception e )
	{
		//throw e;
	}
	return null;
    } 	

    /**
     * getObjectReferenceFromKey returns the Object reference from the objectkey using POA.create_reference_with_id method
     * @param Object Key as String
     * @returns reference an CORBA.Object.
     */
    org.omg.CORBA.Object getObjectReferenceFromKey( String key )
    { 
	org.omg.CORBA.Object theObject = null;
	try
	{
		theObject = nsPOA.create_reference_with_id( key.getBytes( ), NamingContextHelper.id( ) );
	}
	catch (Exception e )
	{
		theObject = null;
	}
        return theObject;
    } 

    /**
     * getObjectKey gets the Object Key from the reference using POA.reference_to_id method
     * @param reference an CORBA.Object.
     * @returns Object Key as String
     */
    String getObjectKey( org.omg.CORBA.Object reference )
    { 
	byte theId[];
	try
	{
		theId = nsPOA.reference_to_id( reference ); 
	}
	catch( org.omg.PortableServer.POAPackage.WrongAdapter e )
	{
		return null;
	}
	catch( org.omg.PortableServer.POAPackage.WrongPolicy e )
	{
		return null;
	}
	catch( Exception e )
	{
		return null;
	}
	String theKey = new String( theId );
	return theKey;
    }

 
}