TransporterImplBean.java

/* Generated by Together */

package multimonster.transporter;
import java.rmi.RemoteException;

import javax.ejb.CreateException;
import javax.ejb.EJBException;
import javax.ejb.RemoveException;
import javax.ejb.SessionBean;
import javax.ejb.SessionContext;
import javax.naming.Context;
import javax.naming.InitialContext;
import javax.naming.NamingException;

import multimonster.common.FormatId;
import multimonster.common.MMThread;
import multimonster.common.ProtocolId;
import multimonster.common.Proxy;
import multimonster.common.media.MOIdentifier;
import multimonster.common.pipe.Pipe;
import multimonster.common.plugin.PlugInIdentifier;
import multimonster.common.plugin.PlugInInformation;
import multimonster.common.setting.Setting;
import multimonster.common.util.EjbCreator;
import multimonster.common.util.EjbHomeGetter;
import multimonster.converter.exceptions.ConverterException;
import multimonster.converter.interfaces.ConverterImpl;
import multimonster.converter.interfaces.ConverterImplHome;
import multimonster.transporter.exceptions.TransporterException;

import org.apache.log4j.Logger;

/**
 * 
 * Transfers data with a protocol to the MediaProxy.
 * 
 * @author J�rg Meier
 *
 * @ejb.bean	name = "TransporterImpl"
 * 				display-name = "TransporterFacade SessionBean"
 * 				description = "The Facade of the Transporter-Package of MultiMonster"
 * 				view-type = "remote"
 * 				jndi-name = "multimonster/transporter/TransporterFacade"
 */
public class TransporterImplBean implements TransporterFacade, SessionBean {

	private SessionContext ctx;
	private Logger log;
	private Context context;
	private ConverterImplHome converterHome;

	public void setSessionContext(SessionContext context) throws RemoteException, EJBException {
		ctx = context;
	}

	public void ejbActivate() throws EJBException {
	}

	public void ejbPassivate() throws EJBException {
	}

	public void ejbRemove() throws EJBException {
	}

	/**
	 * @ejb.create-method 
	 * 
	 * @throws CreateException
	 * @throws EJBException
	 */
	public void ejbCreate() throws CreateException, EJBException {
			log = Logger.getLogger(this.getClass());
		try {
			context = new InitialContext();
			converterHome = EjbHomeGetter.getConverterHome(context);
			
		} catch (NamingException e) {
			log.error(this.getClass().getName() + " Couldn't get referenced EJB-Home-Interfaces.");
		}

	}


	/**
	 * @ejb.interface-method view-type = "remote"
	 * 
	 * Starts data output by returning a Pipe which serves the data
	 * with a protocol.
	 * 
	 */
    public Pipe output(MOIdentifier mOId, FormatId fId, ProtocolId protocolId) throws TransporterException {
		log.debug("output()");
    	return startTransporter(mOId, fId, protocolId, false);
    }

	/**
	 * @ejb.interface-method view-type = "remote"
	 */
   public Pipe input(MOIdentifier mOId, ProtocolId protocolId) throws TransporterException {
		
		log.debug("input() called.");
		return startTransporter(mOId, null, protocolId, true);
    }

	private Pipe startTransporter(MOIdentifier mOId, FormatId fId, ProtocolId protocolId, boolean isInput) throws TransporterException {
		
		Pipe pipeToProxy = null;
		Pipe pipeFromConverter = null;
		String errorText = "";
		ConverterImpl converter = null;
		TransporterPlugInFactory transporterFactory = null;
		TransporterPlugin transporter = null;
		
		// parameter checks
		if (mOId == null) {
			errorText = "mOId was null - aborting.";
			log.error(errorText);
			throw new TransporterException(errorText);			
		} else if (fId == null) {
			log.debug("FormatID is null - can only do input.");
		} else if (protocolId == null) {
			errorText = "protocol was null - aborting.";
			log.error(errorText);
			throw new TransporterException(errorText);
		} else {
			//log.debug("parameter ok.");			
		}

		// get PlugIn for protocol
		transporterFactory = TransporterPlugInFactory.getInstance();		 
		if (transporterFactory == null){
			errorText = "Couldn't get TransporterFactory";
			log.error(errorText);
			throw new TransporterException(errorText);
		}
		try {
			transporter = transporterFactory.getTransporter(protocolId, isInput);
			
		} catch (TransporterException e1) {
			errorText = "TransporterFactory couldn't get PlugIn: " +e1.getMessage();
			log.error(errorText);
			throw new TransporterException(errorText);
		}
		
		// create Pipe to Proxy
		pipeToProxy = new Pipe();
		if (pipeToProxy == null) {
			errorText = "Couldn't create Pipe to Proxy.";
			log.error(errorText);
			throw new TransporterException(errorText);
		}
		
		// start deeper layers by asking the converter for a data-pipe
		try {
			converter = EjbCreator.createConverter(converterHome, context);
			
		} catch (Exception e) {
			errorText = "Couldn't get controller: " +e.getMessage();
			log.error(errorText);
			throw new TransporterException(errorText);
		}
		try {
			// call converter to get data pipe
			if (isInput) {
				//create pipe where Transporter has to insert data for converter
				pipeFromConverter = new Pipe();
				if (pipeFromConverter == null) {
					errorText = "Couldn't create Pipe to Converter.";
					log.error(errorText);
					throw new TransporterException(errorText);
				}				
				converter.addMediaObject(mOId, pipeFromConverter);
				
			} else {			
				pipeFromConverter = converter.getMediaInstance(mOId, fId);
			}
			converter.remove();
			
		} catch (RemoteException e) {
			errorText = "Error calling converter: " +e.getMessage();
			log.error(errorText);
			throw new TransporterException(errorText);
		} catch (RemoveException e) {
			errorText = "Error removing converter: " +e.getMessage();
			log.error(errorText);
			throw new TransporterException(errorText);
		} catch (ConverterException e) {
			errorText = "Got error from converter: " +e.getMessage();
			log.error(errorText);
			throw new TransporterException(errorText);
		}
		if (pipeFromConverter == null){
			errorText = "Got no pipe from converter.";
			log.error(errorText);
			throw new TransporterException(errorText);
		}
		
		// give both Pipes to Transporter-PlugIn
		transporter.setPipes(pipeToProxy, pipeFromConverter);

		// start transporting...
		MMThread transporterThread = new MMThread(transporter);
		transporterThread.start();
		
		//log.debug("Transporter started.");
		
		return pipeToProxy;
    }

	/**
	 * @ejb.interface-method view-type = "remote"
	 */
   public boolean registerProxy(Proxy proxy) {
		return false;
    }

	/**
	 * @ejb.interface-method view-type = "remote"
	 */
    public boolean releaseProxy(Proxy proxy) {
		return false;
    }

	/* (non-Javadoc)
	 * @see multimonster.common.SettingListener#changeSetting(multimonster.common.Setting[])
	 */
	/**
	 * @ejb.interface-method view-type = "remote"
	 */
	public void changeSetting(Setting[] setting) {
		// TODO Auto-generated method stub
		
	}

	/* (non-Javadoc)
	 * @see multimonster.common.Pluggable#addPlugIn(multimonster.common.PlugInInformation)
	 */
	/**
	 * @ejb.interface-method view-type = "remote"
	 */
	public void addPlugIn(PlugInInformation plugInInformation) {
		// TODO Auto-generated method stub
		
	}

	/* (non-Javadoc)
	 * @see multimonster.common.Pluggable#releasePlugIn(multimonster.common.PlugInIdentifier)
	 */
	/**
	 * @ejb.interface-method view-type = "remote"
	 */
	public void releasePlugIn(PlugInIdentifier plugInId) {
		// TODO Auto-generated method stub
		
	}

	/* (non-Javadoc)
	 * @see multimonster.common.Pluggable#removePlugIn(multimonster.common.PlugInIdentifier)
	 */
	/**
	 * @ejb.interface-method view-type = "remote"
	 */
	public void removePlugIn(PlugInIdentifier plugInId) {
		// TODO Auto-generated method stub
		
	}
}