persistentbindingiterator.java

java1.6众多例子参考

/*
 * @(#)PersistentBindingIterator.java	1.11 05/11/17
 *
 * Copyright 2006 Sun Microsystems, Inc. All rights reserved.
 * SUN PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 */
/*
 * @(#)TransientBindingIterator.java	1.36 99/07/16
 * 
 * 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 general CORBA classes
import org.omg.CORBA.SystemException;
import org.omg.CORBA.ORB;
import org.omg.CORBA.INTERNAL;

// Get org.omg.CosNaming Types
import org.omg.CosNaming.Binding;
import org.omg.CosNaming.BindingType;
import org.omg.CosNaming.BindingTypeHolder;
import org.omg.CosNaming.NameComponent;
import org.omg.PortableServer.POA;

// Get base implementation
import com.sun.corba.se.impl.naming.pcosnaming.NamingContextImpl;
import com.sun.corba.se.impl.naming.pcosnaming.InternalBindingValue;

import com.sun.corba.se.impl.naming.cosnaming.BindingIteratorImpl;

// Get a hash table
import java.util.Hashtable;
import java.util.Enumeration;

/**
 * Class TransientBindingIterator implements the abstract methods
 * defined by BindingIteratorImpl, to use with the TransientNamingContext
 * implementation of the NamingContextImpl. The TransientBindingIterator
 * implementation receives a hash table of InternalBindingValues, and uses
 * an Enumeration to iterate over the contents of the hash table.
 * @see BindingIteratorImpl
 * @see TransientNamingContext
 */
public class PersistentBindingIterator extends BindingIteratorImpl
{
    private POA biPOA;
    /**
     * Constructs a new PersistentBindingIterator object.
     * @param orb a org.omg.CORBA.ORB object.
     * @param aTable A hashtable containing InternalBindingValues which is
     * the content of the PersistentNamingContext.
     * @param java.lang.Exception a Java exception.
     * @exception Exception a Java exception thrown of the base class cannot
     * initialize.
   */
    public PersistentBindingIterator(org.omg.CORBA.ORB orb, Hashtable aTable,
        POA thePOA ) throws java.lang.Exception
    {
	super(orb);
	this.orb = orb;
	theHashtable = aTable;
	theEnumeration = this.theHashtable.keys();
	currentSize = this.theHashtable.size();
        biPOA = thePOA;
    }

    /**
   * Returns the next binding in the NamingContext. Uses the enumeration
   * object to determine if there are more bindings and if so, returns
   * the next binding from the InternalBindingValue.
   * @param b The Binding as an out parameter.
   * @return true if there were more bindings.
   */
    final public boolean NextOne(org.omg.CosNaming.BindingHolder b)
    {
	// If there are more elements get the next element
	boolean hasMore = theEnumeration.hasMoreElements();
	if (hasMore) {
            InternalBindingKey theBindingKey =
		 ((InternalBindingKey)theEnumeration.nextElement());
            InternalBindingValue theElement =
		(InternalBindingValue)theHashtable.get( theBindingKey );
	    NameComponent n = new NameComponent( theBindingKey.id, theBindingKey.kind ); 
	    NameComponent[] nlist = new NameComponent[1];
	    nlist[0] = n;
            BindingType theType = theElement.theBindingType;
	    
	    b.value =
	        new Binding( nlist, theType );	
	} else {
	    // Return empty but marshalable binding
	    b.value = new Binding(new NameComponent[0],BindingType.nobject);
	}
	return hasMore;
    }

    /**
   * Destroys this BindingIterator by disconnecting from the ORB
   * @exception org.omg.CORBA.SystemException One of a fixed set of CORBA system exceptions.
   */
    final public void Destroy()
    {
        // Remove the object from the Active Object Map.
        try {
            byte[] objectId = biPOA.servant_to_id( this );
            if( objectId != null ) {
                biPOA.deactivate_object( objectId );
            }
        }
        catch( Exception e ) {
            throw new INTERNAL( "Exception in BindingIterator.Destroy " + e );
        }
    }

    /**
   * Returns the remaining number of elements in the iterator.
   * @return the remaining number of elements in the iterator.   
   */
    public final int RemainingElements() {
	return currentSize;
    }

    private int currentSize;
    private Hashtable theHashtable;
    private Enumeration theEnumeration;
    private org.omg.CORBA.ORB orb;
}