package javax.megaco.message.descriptor;



import java.io.Serializable;





import javax.megaco.ParameterNotSetException;

import javax.megaco.pkg.PkgEventItem;

import javax.megaco.pkg.PkgItemStr;



/**

 * The EventBufParam object is a class that shall be used to set the stream id,

 * event id, package id and parameter name and value for an event id. The class

 * optionally provides interface to specify the package name, item name and the

 * associated parameters in the string format. This is an independent class

 * derived from java.util.Object and shall not have any derived classes.

 */

public class EventBufParam implements Serializable {



	private PkgItemStr eventItemStr;

	private PkgEventItem eventItem;

	private Integer streamId;



	/**

	 * Constructs Event buffer parameter object with the PkgEventItem object.

	 * This is to be set within an event buffer descriptor.

	 * 

	 * @param eventItem

	 * @throws IllegalArgumentException

	 *             - Thrown if an invalid eventItem object reference is set.

	 */

	public EventBufParam(PkgEventItem eventItem) throws IllegalArgumentException {

		this.eventItem = eventItem;

	}



	/**

	 * 

	 * Constructs Event buffer parameter object with the PkgItemStr object. This

	 * method would be used if the package parameters are to be conveyed in the

	 * string format. This is to be set within an event buffer descriptor.

	 * 

	 * @param eventItemStr

	 * @throws IllegalArgumentException

	 *             - Thrown if an invalid eventItemStr object reference is set.

	 */

	public EventBufParam(PkgItemStr eventItemStr) throws IllegalArgumentException {

		this.eventItemStr = eventItemStr;

	}



	/**

	 * The method can be used to get the pkdgName as set in the event buffer

	 * descriptor. This method gives the package information, the attached event

	 * information and the parameter name and value for the event id.

	 * 

	 * @return The object reference for the megaco package, which has the object

	 *         reference for megaco package event and which in turn has the

	 *         reference for the parameter info. If the parameter has not been

	 *         set, then this method shall return NULL.

	 */

	public PkgEventItem getMegacoPkgEvtItem() {

		return this.eventItem;

	}



	/**

	 * The method can be used to get the pkdgName as set in the event buffer

	 * descriptor. This method gives the package information, the attached event

	 * information and the parameter name and value. As comapres to the

	 * getMegacoPkgEvtItem() method, this method returnes the package parameters

	 * in the string format.

	 * 

	 * @return The object reference for the megaco package item. This class

	 *         holds information about package name, item name and the

	 *         parameters in the string format. If the parameter has not been

	 *         set, then this method shall return NULL.

	 */

	public PkgItemStr getMegacoPkgItemStr() {

		return this.eventItemStr;

	}



	/**

	 * The method can be used to get stream id in the event buffer descriptor.

	 * 

	 * @return streamId - The integer value of the stream id shall be returned.

	 *         This shall be returned only if the streamId is present in the

	 *         event parameter of the event buffer descriptor.

	 * @throws javax.megaco.ParameterNotSetException

	 *             - Thrown if streamId has not been set. Thus this method

	 *             should be called only after verifying that the streamId is

	 *             set using isStreamIdPresen

	 */

	public int getStreamId() throws javax.megaco.ParameterNotSetException {

		if (!isStreamIdPresent()) {

			throw new ParameterNotSetException("StreamId must be present");

		}



		return this.streamId.intValue();

	}



	/**

	 * The method can be used to set stream id in the event buffer descriptor.

	 * This automatically sets the value of stream id present in the event

	 * parameter object to true.

	 * 

	 * @param streamId

	 *            - The integer value of the stream id shall be set.

	 * @throws IllegalArgumentException

	 *             - Thrown if streamId is set with an invalid value.

	 */

	public void setStreamId(int streamId) throws IllegalArgumentException {



		if (streamId <= 0) {

			throw new IllegalArgumentException("StreamId must be greater than zero.");

		}



		this.streamId = new Integer(streamId);

	}



	/**

	 * The method can be used to find if the stream id is present in the current

	 * object.

	 * 

	 * @return Returns true if the stream id is present. This needs to be

	 *         checked before getting the stream id from this object.

	 */

	public boolean isStreamIdPresent() {

		return this.streamId != null;

	}



	public java.lang.String toString()



	{

		return super.toString();

	}



}