www.pudn.com > chap8.rar > MailboxDOMProducer.java

package chap8; 
 
import java.util.Iterator; 
import java.text.SimpleDateFormat; 
import javax.xml.parsers.*; 
import org.w3c.dom.*; 
 
/** 
 * Converts a Mailbox into a DOM tree. 
 */ 
public class MailboxDOMProducer { 
    // controls how dates are formatted 
    private static SimpleDateFormat sdFmt = new SimpleDateFormat( 
            "MMM dd, yyyy HH:mm:ss a"); 
 
    /** 
     * A simple unit test that produces XML for a Mailbox to System.out. 
     */ 
    public static void main(String[] args) throws Exception { 
        Mailbox mbox = MailboxFactory.getMailbox("burke_e"); 
        Document doc = createMailboxDocument(mbox, Mailbox.INBOX); 
 
        System.out.println( 
                com.oreilly.javaxslt.util.DOMUtil.domToString(doc)); 
    } 
 
    /** 
     * @param mailbox the Mailbox to produce DOM for. 
     * @param curFolderName the currently selected folder. 
     * @return DOM for a Mailbox object. 
     */ 
    public static Document createMailboxDocument(Mailbox mailbox, 
            String curFolderName) throws ParserConfigurationException { 
        // use JAXP to create a DOM Document 
        DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance(); 
        DocumentBuilder db = dbf.newDocumentBuilder(); 
        Document doc = db.newDocument(); 
 
        // the root element is  
        Element mailboxElem = doc.createElement("mailbox"); 
        doc.appendChild(mailboxElem); 
 
        //  contains  
        Element usernameElem = doc.createElement("username"); 
        mailboxElem.appendChild(usernameElem); 
 
        // the mailbox may be null. In this case, we are done. 
        if (mailbox != null) { 
            usernameElem.appendChild(doc.createTextNode(mailbox.getUsername())); 
 
            // create the following: 
            //  
            //   A Folder Name 
            //   Another Folder Name 
            //  
            Element foldersElem = doc.createElement("folders"); 
            mailboxElem.appendChild(foldersElem); 
            Iterator folderNames = mailbox.getFolderNames(); 
            while (folderNames.hasNext()) { 
                String curName = (String) folderNames.next(); 
                Element curFolderElem = doc.createElement("name"); 
                curFolderElem.appendChild(doc.createTextNode(curName)); 
                foldersElem.appendChild(curFolderElem); 
            } 
 
            // pick a default folder if the current folder name is invalid 
            if (!mailbox.containsFolder(curFolderName)) { 
                curFolderName = Mailbox.INBOX; 
            } 
 
            // create the following: 
            //   
            //     Folder Name 
            //     ...zero or more  elements 
            //   
            Element folderElem = doc.createElement("folder"); 
            mailboxElem.appendChild(folderElem); 
 
            Element nameElem = doc.createElement("name"); 
            nameElem.appendChild(doc.createTextNode(curFolderName)); 
            folderElem.appendChild(nameElem); 
 
            // add all of the  elements to the  
            MailFolder curFolder = mailbox.getFolder(curFolderName); 
            Iterator iter = curFolder.getMessages(); 
            while (iter.hasNext()) { 
                MessageHeader curHeader = (MessageHeader) iter.next(); 
                folderElem.appendChild(createMessageHeaderElement( 
                        doc, curHeader)); 
            } 
        } 
 
        return doc; 
    } 
 
    /** 
     * Produce a  element. 
     */ 
    public static Element createMessageHeaderElement(Document doc, 
            MessageHeader msgHeader) { 
        Element msgHdrElem = doc.createElement("messageHeader"); 
        msgHdrElem.setAttribute("id", Long.toString(msgHeader.getID())); 
 
        Element fromElem = doc.createElement("from"); 
        fromElem.appendChild(doc.createTextNode(msgHeader.getFrom())); 
        msgHdrElem.appendChild(fromElem); 
 
        Element toElem = doc.createElement("to"); 
        toElem.appendChild(doc.createTextNode(msgHeader.getTo())); 
        msgHdrElem.appendChild(toElem); 
 
        Element subjectElem = doc.createElement("subject"); 
        subjectElem.appendChild(doc.createTextNode(msgHeader.getSubject())); 
        msgHdrElem.appendChild(subjectElem); 
 
        // produce the following: 
        //  DateAndTime 
        Element whenReceivedElem = doc.createElement("whenReceived"); 
        whenReceivedElem.appendChild(doc.createTextNode( 
                sdFmt.format(msgHeader.getWhenReceived()))); 
        whenReceivedElem.setAttribute("sortKey", 
                String.valueOf(msgHeader.getWhenReceived().getTime())); 
        msgHdrElem.appendChild(whenReceivedElem); 
 
        return msgHdrElem; 
    } 
 
    // prevent instantiation of this class 
    private MailboxDOMProducer() { 
    } 
}