org.joseki.Response Maven / Gradle / Ivy

Go to download
/*
 * (c) Copyright 2005, 2006, 2007, 2008, 2009 Hewlett-Packard Development Company, LP
 * All rights reserved.
 * [See end of file]
 */

package org.joseki;

import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import com.hp.hpl.jena.query.ResultSet;
import com.hp.hpl.jena.rdf.model.Model;


abstract public class Response
{
    private static Logger log = LoggerFactory.getLogger(Response.class) ;

    private List callbacks = new ArrayList() ;
    
    private Model responseModel = null ;
    private ResultSet responseResultSet = null ;
    private Boolean responseBoolean = null ;
    private boolean responseNothing = false ; 
    
    private boolean done = false ;
    protected Request request ;
    
    protected Response(Request request)
    { this.request = request ; }
    
    public void addCallback(ResponseCallback callback)
    { 
        // Add at front - called in reverse order added (nesting)
        callbacks.add(0, callback) ;
    }
    
    public void setModel(Model model) throws QueryExecutionException
    { checkState() ; this.responseModel = model ; }
    
    public void setResultSet(ResultSet rs) throws QueryExecutionException
    { checkState() ; this.responseResultSet = rs ; }
    
    public void setBoolean(boolean b) throws QueryExecutionException
    { checkState() ; this.responseBoolean = new Boolean(b) ; }
    

    public void setOK() throws QueryExecutionException
    { checkState() ; this.responseNothing = true ; }
    
    public void sendException(ExecutionException execEx)
    {
        if ( done )
        {
            log.error("doException: Response already sent: "+request.getServiceURI()) ;
            return ;
        }
        doException(execEx) ;
        doCallbacks(false) ;
    }
    
    public void sendResponse() throws QueryExecutionException
    {
        if ( done )
        {
            log.warn("Already sent response") ;
            return ;
        }
        
        if ( responseModel == null && responseResultSet == null && responseBoolean == null && ! responseNothing )
        {
            log.warn("Response not set") ;
            throw new QueryExecutionException(ReturnCodes.rcInternalError,
                                              "Nothing to send as response") ;
        }
        
        done = true ;
        if ( responseModel != null )
            doResponseModel(responseModel) ;
        
        if ( responseResultSet != null )
            doResponseResultSet(responseResultSet) ;
        
        if ( responseBoolean != null )
            doResponseBoolean(responseBoolean) ;
        
        if ( responseNothing )
            doResponseNothing() ;

        responseModel = null ;
        responseResultSet = null ;
        responseBoolean = null ;
        
        doCallbacks(true) ;
        return ;
    }
    
    private void doCallbacks(boolean successfulOperation)
    {
        for ( Iterator iter = callbacks.iterator() ; iter.hasNext(); )
        {
            ResponseCallback callback = iter.next();
            callback.callback(successfulOperation) ;
        }
    }
    
    abstract protected void doResponseNothing() throws QueryExecutionException ;

    abstract protected void doResponseModel(Model model) throws QueryExecutionException ;
    
    abstract protected void doResponseResultSet(ResultSet resultSet) throws QueryExecutionException ;

    abstract protected void doResponseBoolean(Boolean bool) throws QueryExecutionException ;
    
    abstract protected void doException(ExecutionException execEx) ;
    
    private void checkState() throws QueryExecutionException
    {
       if ( done )
       {
           log.warn("State error: already done") ;
           throw new QueryExecutionException(ReturnCodes.rcInternalError,
                                             "State error: already done") ;
       }
       if ( responseModel != null )
       {
           log.warn("State error: model already set") ;
           throw new QueryExecutionException(ReturnCodes.rcInternalError,
                                             "State error: model already set") ;
       }
       if ( responseResultSet != null )
       {
           log.warn("State error: result set already set") ;
           throw new QueryExecutionException(ReturnCodes.rcInternalError,
                                             "State error: result set already set") ;
       }
    }

}

/*
 * (c) Copyright 2005, 2006, 2007, 2008, 2009 Hewlett-Packard Development Company, LP
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. The name of the author may not be used to endorse or promote products
 *    derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */