since: JavaMail - 1.1

 protected Multipart() 
{

}

Default constructor. An empty Multipart object is created.

 public synchronized  void addBodyPart(BodyPart part) throws MessagingException 
{
	if (parts == null)
	    parts = new Vector();
	parts.addElement(part);
	part.setParent(this);
}

Adds a Part to the multipart. The BodyPart is appended to the list of existing Parts.

 public synchronized  void addBodyPart(BodyPart part,
    int index) throws MessagingException 
{
	if (parts == null)
	    parts = new Vector();
	parts.insertElementAt(part, index);
	part.setParent(this);
}

Adds a BodyPart at position index. If index is not the last one in the list, the subsequent parts are shifted up. If index is larger than the number of parts present, the BodyPart is appended to the end.

 public synchronized BodyPart getBodyPart(int index) throws MessagingException 
{
	if (parts == null)
	    throw new IndexOutOfBoundsException("No such BodyPart");
	return (BodyPart)parts.elementAt(index);
}

Get the specified Part. Parts are numbered starting at 0.

 public String getContentType() 
{
	return contentType;
}

Return the content-type of this Multipart.

This implementation just returns the value of the contentType field.

 public synchronized int getCount() throws MessagingException 
{
	if (parts == null)
	    return 0;
	return parts.size();
}

Return the number of enclosed BodyPart objects.

 public synchronized Part getParent() 
{
	return parent;
}

Return the Part that contains this Multipart object, or null if not known.

 public synchronized boolean removeBodyPart(BodyPart part) throws MessagingException 
{
	if (parts == null)
	    throw new MessagingException("No such body part");
	boolean ret = parts.removeElement(part);
	part.setParent(null);
	return ret;
}

Remove the specified part from the multipart message. Shifts all the parts after the removed part down one.

 public synchronized  void removeBodyPart(int index) throws MessagingException 
{
	if (parts == null)
	    throw new IndexOutOfBoundsException("No such BodyPart");
	BodyPart part = (BodyPart)parts.elementAt(index);
	parts.removeElementAt(index);
	part.setParent(null);
}

Remove the part at specified location (starting from 0). Shifts all the parts after the removed part down one.

 protected synchronized  void setMultipartDataSource(MultipartDataSource mp) throws MessagingException 
{
	contentType = mp.getContentType();
	int count = mp.getCount();
	for (int i = 0; i <  count; i++)
	    addBodyPart(mp.getBodyPart(i));
}

Setup this Multipart object from the given MultipartDataSource.

The method adds the MultipartDataSource's BodyPart objects into this Multipart. This Multipart's contentType is set to that of the MultipartDataSource.

This method is typically used in those cases where one has a multipart data source that has already been pre-parsed into the individual body parts (for example, an IMAP datasource), but needs to create an appropriate Multipart subclass that represents a specific multipart subtype.

 public synchronized  void setParent(Part parent) 
{
	this.parent = parent;
}

Set the parent of this Multipart to be the specified Part. Normally called by the Message or BodyPart setContent(Multipart) method. parent may be null if the Multipart is being removed from its containing Part.

 abstract public  void writeTo(OutputStream os) throws IOException, MessagingException
Output an appropriately encoded bytestream to the given
OutputStream. The implementation subclass decides the
appropriate encoding algorithm to be used. The bytestream
is typically used for sending.