ejbasyncresult.java

本文介绍了一种EJB异步调用方法,使得客户端能够方便地异步调用EJB

/**
 * javax.ejb.async - Proposed Classes/Interfaces for EJB Async support
 *
 * @version     1.1
 * @author      Andrzej Jan Taramina, Chaeron Consulting Corporation
 */
	
package javax.ejb.async;

//***************************************************************************
//*
//*		Imports
//*
//***************************************************************************/

import java.io.Serializable;
import java.rmi.*;
import javax.ejb.*;


//***************************************************************************
//*
//*		EJBAsyncResult Class definition
//*
//***************************************************************************/

/**
 * The </code>EJBAsyncResult</code> class is used by the EJB Server/Container to
 * return the Bean's remote method invocation return value or exception to the users
 * callback (</code>EJBAsyncCallback</code>)routine for asynchronous invocations.
 *
 * @see	   javax.ejb.async.EJBAsyncCallback
 *
 * @author  Andrzej Jan Taramina, Chaeron Consulting Corporation
 * @version 1.1, 03/17/99
 */
 
public class EJBAsyncResult implements Serializable
{

	//***************************************************************************
	//*
	//*		Constant definitions
	//*
	//***************************************************************************/
	
	
	//***************************************************************************
	//*
	//*		Attributes
	//*
	//***************************************************************************/

	private EJBObject		source			= null;
	private Serializable	result			= null;
	private Exception		exception 		= null;
	private Object			clientContext	= null;
	
	
	//***************************************************************************
	//*
	//*		EJBAsyncResult methods
	//*
	//***************************************************************************/
	
	/**
	* Constructs an EJBAsyncResult with no result/exception information set.  You will need
	* to use the setResult() or setException() methods to set this information.  You will also
	* need to set the source EJBObject.
	*
	* @see	   javax.ejb.async.EJBAsyncResult#setResult(Serializable)
	* @see	   javax.ejb.async.EJBAsyncResult#setException(Exception)
	* @see	   javax.ejb.async.EJBAsyncResult#setSource(EJBObject)
	*/
		
  	public EJBAsyncResult() 
	{
	  	super();
  	}
		
	/**
	* Constructs an EJBAsyncResult with the specified exception. You will also
	* need to set the source EJBObject.
	*
	* @param   exception   The remote method invocation exception.
	*
	* @see	   javax.ejb.async.EJBAsyncResult#setSource(EJBObject)
	*/
	
	public EJBAsyncResult( Exception exception ) 
	{
	  	super();
		
		this.exception 	= exception;
  	}
		
	/**
	* Constructs an EJBAsyncResult with the specified result object. You will also
	* need to set the source EJBObject.
	*
	* @param   result   The remote method invocation return value.
	*
	* @see	   javax.ejb.async.EJBAsyncResult#setSource(EJBObject)
	*/
	
	public EJBAsyncResult( Serializable result ) 
	{
	  	super();
			
		this.result = result;
  	}
		
	/**
	* Constructs an EJBAsyncResult with no result/exception information set.  You will need
	* to use the setResult() or setException() methods to set this information.
	*
	* @param   source   The EJBObject used to create the result.
	*
	* @see	   javax.ejb.async.EJBAsyncResult#setResult(Serializable)
	* @see	   javax.ejb.async.EJBAsyncResult#setException(Exception)
	*/
		
  	public EJBAsyncResult( EJBObject source ) 
	{
	  	super();
			
		this.source = source;
  	}
		
	/**
	* Constructs an EJBAsyncResult with the specified exception.
	*
	* @param   source   The EJBObject used to create the result.
	* @param   exception   The remote method invocation exception.
	*/
	
	public EJBAsyncResult( EJBObject source, Exception exception ) 
	{
	  	super();
		
		this.source 	= source;
		this.exception 	= exception;
  	}
		
	/**
	* Constructs an EJBAsyncResult with the specified result object.
	*
	* @param   source   The EJBObject used to create the result.
	* @param   result   The remote method invocation return value.
	*/
	
	public EJBAsyncResult( EJBObject source, Serializable result ) 
	{
	  	super();
			
		this.source = source;
		this.result = result;
  	}


	
	//***************************************************************************
	//*
	//*		Accessor Methods
	//*
	//***************************************************************************/
	
	/**
	* Get the remote method result.  If the remote method threw an exception, then
	* this exception will be rethrown by this method.
	*
	* @return  The return value of the remote method invocation
	* @exception  Exception  If the remote method invocation threw an exception
	*
	* @see	   javax.ejb.async.EJBAsyncResult#setResult(Serializable)
	*/

	public Object getResult() throws Exception
	{
		if( exception != null ) {
			throw( exception );
		}
		
		return( result );
	}
	
	
	/**
	* Set the remote method result.  This method should only used by the EJB Server.
	*
	* @param	result The return value of the remote method invocation
	* @see	   	javax.ejb.async.EJBAsyncResult#getResult
	*/

	public void setResult( Serializable result )
	{
		this.result = result;	
	}
	
	
	/**
	* Set the exception.  This method should only used by the EJB Server.
	*
	* @param	exception The exception thrown by the remote method invocation
	*/

	public void setException( Exception exception )
	{
		this.exception = exception;
	}
	
	/**
	* Get the source EJBObject that returned this result.  
	*
	* @return  The EJBObject that returned this result.
	*
	* @see	   javax.ejb.async.EJBAsyncResult#setSource(EJBObject)
	*/

	public EJBObject getSource() throws Exception
	{
		return( source );
	}
	
	
	/**
	* Set the source EJB Object that created this result.  
	* This method should only used by the EJB Server, and should be used on the 
	* client side to set the EJBObject before calling the users EJBAsyncCallback.
	*
	* @param	source The EJB Object that created this result
	* @see	   	javax.ejb.async.EJBAsyncResult#getSource
	*/

	public void setSource( EJBObject source )
	{
		this.source = source;	
	}
	
	/**
	* Get the the clientContext that the user included with the original method invocation.  
	*
	* @return  The Client Context object.
	*
	* @see	   javax.ejb.async.EJBAsyncResult#setClientContext(Object)
	*/

	public Object getClientContext() throws Exception
	{
		return( clientContext );
	}
	
	
	/**
	* Set client context that the user included in the original method invocation.  
	* This method should only used by the EJB Server, and should be used on the 
	* client side to set the client context before calling the users EJBAsyncCallback.
	*
	* @param	context The client context Object that the user passed in.
	* @see	   	javax.ejb.async.EJBAsyncResult#getClientContext
	*/

	public void setClientContext( Object context )
	{
		this.clientContext = context;	
	}
	
}