Develop Reference

Building XML document in lowercase or TitleCase - flag based

In my current project, we are in the process of re-factoring a java class that constructs an XML document. In previous versions of the product delivered to the customer, the XML document is built with lower case elements and attributes:
<rootElement attr = "abc">
<childElement childAttr = "xyz"/>
</rootElement>
But now we have a requirement to build the XML document with TitleCase element and attributes. The user will set a flag in a properties file to indicate whether the document should be built in lower case or title case. If the flag is configured to build the document in TitleCase, the resultant document will look like:
<RootElement Attr = "abc">
<ChildElement ChildAttr = "xyz">
</RootElement>
Various approaches to solve the problem:
1. Plugging in a transformer to convert lowercase XML document to TitleCase XML document. But this will impact the overall performance, as we deal with huge XML files spanning more than 10,000 lines.
2. Create two separate maps with corr. XML elements and attributes.
For eg:
lowercase map: rootelement -> rootElement, attr -> attr ....
TitelCase map: rootlement -> RootElement, attr -> Attr ....
Based on the property set by the user, the corr. map will be chosen and XML element/attributes from this map will be used to build the XML document.
3. Using enum to define constants and its corr. values.
public enum XMLConstants {
ROOTELEMENT("rootElement", "RootElement"),
ATTRIBUTE("attr", "Attr");
private String lowerCase;
private String titleCase;
private XMLConstants(String aLowerCase, String aTitleCase){
titleCase = aTitleCase;
lowerCase = aLowerCase;
}
public String getValue(boolean isLowerCase){
if(isLowerCase){
return lowerCase;
} else {
return titleCase;
}
}
}
--------------------------------------------------------------
// XML document builder
if(propertyFlag){
isLowerCase = false;
} else {
isLowerCase = true;
}
....
....
createRootElement(ROOTELEMENT.getValue(isLowerCase));
createAttribute(ATTRIBUTE.getValue(isLowerCase));
Please help me choose the right option keeping in mind the performance aspect of the entire solution. If you have any other suggestions, please let me know.

// set before generate XML
boolean isUpperCase;
// use function for each tag/attribute name instead of string constant
// smth. like getInCase("rootElement")
String getInCase(String initialName) {
String intialFirstCharacter = initialName.substring(0, 1);
String actualFirstCharacter;
if (isUpperCase) {
actualFirstCharacter = intialFirstCharacter.toUpperCase();
} else {
actualFirstCharacter = intialFirstCharacter.toLowerCase();
}
return actualFirstCharacter + initialName.substring(1);
}

Extracting Values From an XML File Either using XPath, SAX or DOM for this Specific Scenario

I am currently working on an academic project, developing in Java and XML. Actual task is to parse XML, passing required values preferably in HashMap for further processing. Here is the short snippet of actual XML.
<root>
<BugReport ID = "1">
<Title>"(495584) Firefox - search suggestions passes wrong previous result to form history"</Title>
<Turn>
<Date>'2009-06-14 18:55:25'</Date>
<From>'Justin Dolske'</From>
<Text>
<Sentence ID = "3.1"> Created an attachment (id=383211) [details] Patch v.2</Sentence>
<Sentence ID = "3.2"> Ah. So, there's a ._formHistoryResult in the....</Sentence>
<Sentence ID = "3.3"> The simple fix it to just discard the service's form history result.</Sentence>
<Sentence ID = "3.4"> Otherwise it's trying to use a old form history result that no longer applies for the search string.</Sentence>
</Text>
</Turn>
<Turn>
<Date>'2009-06-19 12:07:34'</Date>
<From>'Gavin Sharp'</From>
<Text>
<Sentence ID = "4.1"> (From update of attachment 383211 [details])</Sentence>
<Sentence ID = "4.2"> Perhaps we should rename one of them to _fhResult just to reduce confusion?</Sentence>
</Text>
</Turn>
<Turn>
<Date>'2009-06-19 13:17:56'</Date>
<From>'Justin Dolske'</From>
<Text>
<Sentence ID = "5.1"> (In reply to comment #3)</Sentence>
<Sentence ID = "5.2"> &gt; (From update of attachment 383211 [details] [details])</Sentence>
<Sentence ID = "5.3"> &gt; Perhaps we should rename one of them to _fhResult just to reduce confusion?</Sentence>
<Sentence ID = "5.4"> Good point.</Sentence>
<Sentence ID = "5.5"> I renamed the one in the wrapper to _formHistResult. </Sentence>
<Sentence ID = "5.6"> fhResult seemed maybe a bit too short.</Sentence>
</Text>
</Turn>
.....
and so on
</BugReport>
There are many commenter like 'Justin Dolske' who have commented on this report and what I actually looking for is the list of commenter and all sentences they have written in a whole XML file. Something like if(from == justin dolske) getHisAllSentences(). Similarly for other commenters (for all). I have tried many different ways to get the sentences only for 'Justin dolske' or other commenters, even in a generic form for all using XPath, SAX and DOM but failed. I am quite new to these technologies including JAVA and any don't know how to achieve it.
Can anyone guide me specifically how could I get it with any of above technologies or is there any other better strategy to do it?
(Note: Later I want to put it in a hashmap such as like this HashMap (key, value) where key = name of commenter (justin dolske) and value is (all sentences))
Urgent help will be highly appreciated.

There're several ways using which you can achieve your requirement.
One way would be use JAXB. There're several tutorials available on this on the web, so feel free to refer to them.
You can also think of creating a DOM and then extracting data from it and then put it into your HashMap.
One reference implementation would be something like this:
import java.io.File;
import java.util.ArrayList;
import java.util.HashMap;
import javax.xml.parsers.DocumentBuilderFactory;
import org.w3c.dom.Document;
import org.w3c.dom.Element;
import org.w3c.dom.NodeList;
public class XMLReader {
private HashMap<String,ArrayList<String>> namesSentencesMap;
public XMLReader() {
namesSentencesMap = new HashMap<String, ArrayList<String>>();
}
private Document getDocument(String fileName){
Document document = null;
try{
document = DocumentBuilderFactory.newInstance().newDocumentBuilder().parse(new File(fileName));
}catch(Exception exe){
//handle exception
}
return document;
}
private void buildNamesSentencesMap(Document document){
if(document == null){
return;
}
//Get each Turn block
NodeList turnList = document.getElementsByTagName("Turn");
String fromName = null;
NodeList sentenceNodeList = null;
for(int turnIndex = 0; turnIndex < turnList.getLength(); turnIndex++){
Element turnElement = (Element)turnList.item(turnIndex);
//Assumption: <From> element
Element fromElement = (Element) turnElement.getElementsByTagName("From").item(0);
fromName = fromElement.getTextContent();
//Extracting sentences - First check whether the map contains
//an ArrayList corresponding to the name. If yes, then use that,
//else create a new one
ArrayList<String> sentenceList = namesSentencesMap.get(fromName);
if(sentenceList == null){
sentenceList = new ArrayList<String>();
}
//Extract sentences from the Turn node
try{
sentenceNodeList = turnElement.getElementsByTagName("Sentence");
for(int sentenceIndex = 0; sentenceIndex < sentenceNodeList.getLength(); sentenceIndex++){
sentenceList.add(((Element)sentenceNodeList.item(sentenceIndex)).getTextContent());
}
}finally{
sentenceNodeList = null;
}
//Put the list back in the map
namesSentencesMap.put(fromName, sentenceList);
}
}
public static void main(String[] args) {
XMLReader reader = new XMLReader();
reader.buildNamesSentencesMap(reader.getDocument("<your_xml_file>"));
for(String names: reader.namesSentencesMap.keySet()){
System.out.println("Name: "+names+"\tTotal Sentences: "+reader.namesSentencesMap.get(names).size());
}
}
}
Note: This is just a demonstration and you would need to modify it to suit your need. I've created it based on your XML to show one way of doing it.

I suggest to use JAXB to creates a Data Model reflecting your XML structure.
One done, you can load the XML into Java instances.
Put each 'Turn' into a Map< String, List< Turn >>, using Turn.From as key.
Once done, you'll can write:
List< Turn > justinsTurn = allTurns.get( "'Justin Dolske'" );

getChildNodes() returns NULL for my root in XML

My goal : to get the root of the XML in a Node object , and then evaluate it !
My problem :
I'm trying to evaluate my expression from the ROOT of the XML file, I have this method ( I need to implement is) :
public Object evaluate(String expression, QName returnType);
Assume that I've already opened the XML with Document , like this :
//load the document into a DOM Document
this.domFactory = DocumentBuilderFactory.newInstance();
domFactory.setNamespaceAware(true); // never forget this!
this.builder = domFactory.newDocumentBuilder();
this.doc = builder.parse("books.xml");
//create an XPath factory
this.factory = XPathFactory.newInstance();
//create an XPath Object
this.xpath = factory.newXPath();
Now when I do this , inside public Object evaluate(String expression, QName returnType);
:
String unitedString = " my characters " ;
rootNode = doc.getChildNodes().item(0);
System.out.println(rootNode.getNodeName()); // this line presents the name of the root
Object returnedObject= xpath.evaluate(unitedString,rootNode ,returnType); // this line makes eclipse go crazy
Eclispe says after line "4" : " DTMManagerDefault.getDTMHandleFromNode(Node) line: not available "
But in line "3" , Eclipse produces the name of the root , which is inventory ...
So where did I go wrong ?
What's wrong with it ?
Thank you all , Jack

first:
Your unitedString is not a valid xPath expression, it should be something like /root/node/ xPath's describe paths to (a) specific node(s) to in your xml file.
second:
The root node of any xml is a special node called the DocumentElement, you can get to it by calling doc.getDocumentElement()

parsing xml in java- multiple child elements

I want to parse xml elemets using java.I m succeeded in some part...But not sure how to do rest..I have xml as,
<MainTag>
<userid>user1</userid>
<country>US</country>
<city>LA</city>
<phone>
<number>1111111111</number>
</phone>
<phone>
<number>222222222</number>
</phone>
</MainTag>
<MainTag>
<userid>user2</userid>
<country>Aus</country>
<city>MB</city>
<phone>
<number>23233</number>
</phone>
<phone>
<number>8787822</number>
</phone>
<phone>
<number>10101</number>
</phone>
I am able to parse xml elements such as country,city etc as below.
public void endelement()
{
if (someText.equalsIgnoreCase("country"))
{
pojo.setCountry(Val);
}
else if(someText.equalsIgnoreCase("city"))
{
pojo.setCity(Val);
}
}
public void stratelement()
{
............
}
But in case of phone how I can parse it ? since one user has multiple phone nos.
I want to find multiple phone nos for particular user.
for e.g. in above xml
for user1 there are two phone nos.
for user2 there are three phone nos.
Can anybody help in this ? Thanks in advance.

I would recommend using JAXB, since it appears you are attempting to bind your xml to a POJO.
Looking at the code you have written here (and assuming that the example xml you have provided is a snippet of well formed xml), I am guess that your pojo object should have a member for phone numbers that is of type List<String>, and your pojo should have a method that allows you to add a phone number to the List (perhaps addPhoneNumber(String phoneNumber) {...})

First, that is not a well-formed XML (as it has two root elements) and you can't parse it with any parser API unless it is well-formed. Now, to parse the XML you would normally use the APIs meant for it like SAX, DOM or StAX or even better the JAXB binding API.
Since you seem to be new to this, I suggest you start learning JAXP. Use StAX instead of DOM or SAX.

you can use DocumetBuilderFactory java default class if you know the incoming xml format for example how many node it has and the names it is very simple look at this code ;
DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
try {
//documentBuilder instance
DocumentBuilder db = dbf.newDocumentBuilder();
Document dom = db.parse("employees.xml");
}catch(ParserConfigurationException pce) {
pce.printStackTrace();
}catch(SAXException se) {
se.printStackTrace();
}catch(IOException ioe) {
ioe.printStackTrace();
}
//and than get root element
Element de= dom.getDocumentElement();
//get the nodelist of main element
NodeList nl = de.getElementsByTagName("Employee");
if(nl != null && nl.getLength() > 0) {
for(int i = 0 ; i < nl.getLength();i++) {
//get the employee element
Element el = (Element)nl.item(i);
}
}
//and then get data
private void getEmployee(Element el) {
//for each <employee> element get values
String name = getTextValue(el,"Name");
int id = getIntValue(el,"Id");
int age = getIntValue(el,"Age");
//get any element attribute
//String type = el.getAttribute("type");
}
thats all

org.xml.sax.SAXParseException: Reference is not allowed in prolog

I am trying to escape html characters of a string and use this string to build a DOM XML using parseXml method shown below. Next, I am trying to insert this DOM document into database. But, when I do that I am getting the following error:
org.xml.sax.SAXParseException: Reference is not allowed in prolog.
I have three questions:
1) I am not sure how to escape double quotes. I tried replaceAll("\"", """) and am not sure if this is right.
2) Suppose I want a string starting and ending with double quotes (eg: "sony"), how do I code it? I tried something like:
String sony = "\"sony\""
Is this right? Will the above string contain "sony" along with double quotes or is there another way of doing it?
3)I am not sure what the "org.xml.sax.SAXParseException: Reference is not allowed in prolog." error means. Can someone help me fix this?
Thanks,
Sony
Steps in my code:
Utils. java
public static String escapeHtmlEntities(String s) {
return s.replaceAll("&", "&").replaceAll("<", "<").replaceAll(">", ">").replaceAll("\"", """).
replaceAll(":", ":").replaceAll("/", "/");
}
public static Document parseXml (String xml) throws Exception {
DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
factory.setNamespaceAware(true);
DocumentBuilder builder = factory.newDocumentBuilder();
Document doc = builder.parse(new InputSource(new StringReader(xml)));
doc.setXmlStandalone(false);
return doc;
}
TreeController.java
protected void notifyNewEntryCreated(String entryType) throws Exception {
for (Listener l : treeControlListeners)
l.newEntryCreated();
final DomNodeTreeModel domModel = (DomNodeTreeModel) getModel();
Element parent_item = getSelectedEntry();
String xml = Utils.escapeHtmlEntities("<entry xmlns=" + "\"http://www.w3.org/2005/atom\"" + "xmlns:libx=" +
"\"http://libx.org/xml/libx2\">" + "<title>" + "New" + entryType + "</title>" +
"<updated>2010-71-22T11:08:43z</updated>" + "<author> <name>LibX Team</name>" +
"<uri>http://libx.org</uri>" + "<email>libx.org#gmail.com</email></author>" +
"<libx:" + entryType + "></libx:" + entryType + ">" + "</entry>");
xmlModel.insertNewEntry(xml, getSelectedId());
}
XMLDataModel.java
public void insertNewEntry (String xml, String parent_id) throws Exception {
insertNewEntry(Utils.parseXml(xml).getDocumentElement(), parent_id);
}
public void insertNewEntry (Element elem, String parent_id) throws Exception {
// inserting an entry with no libx: tag will create a storage leak
if (elem.getElementsByTagName("libx:package").getLength() +
elem.getElementsByTagName("libx:libapp").getLength() +
elem.getElementsByTagName("libx:module").getLength() < 1) {
// TODO: throw exception here instead of return
return;
}
XQPreparedExpression xqp = Q.get("insert_new_entry.xq");
xqp.bindNode(new QName("entry"), elem.getOwnerDocument(), null);
xqp.bindString(new QName("parent_id"), parent_id, null);
xqp.executeQuery();
xqp.close();
updateRoots();
}
insert_new_entry.xq
declare namespace libx='http://libx.org/xml/libx2';
declare namespace atom='http://www.w3.org/2005/atom';
declare variable $entry as xs:anyAtomicType external;
declare variable $parent_id as xs:string external;
declare variable $feed as xs:anyAtomicType := doc('libx2_feed')/atom:feed;
declare variable $metadata as xs:anyAtomicType := doc('libx2_meta')/metadata;
let $curid := $metadata/curid
return replace value of node $curid with data($curid) + 1,
let $newid := data($metadata/curid) + 1
return insert node
{$newid}{
$entry//
}
into $feed,
let $newid := data($metadata/curid) + 1
return if ($parent_id = 'root') then ()
else
insert node http://libx.org/xml/libx2' /> into
$feed/atom:entry[atom:id=$parent_id]//(libx:module|libx:libapp|libx:package)

To escape a double quote, use the " entity, which is predefined in XML.
So, your example string, say an attribute value, will look like
<person name=""sony""/>
There is also &apos; for apostrophe/single quote.
I see you have lots of replaceAll calls, but the replacements seem to be the same? There are some other characters that cannot be used literally, but should be escaped:
& --> &
> --> >
< --> <
" --> "
' --> &apos;
(EDIT: ok, I see this is just formatting - the entities are being turned into they're actual values when being presented by SO.)
The SAX exception is the parser grumbling because of the invalid XML.
As well as escaping the text, you will need to ensure it adheres to the well-formedness rules of XML. There's quite a bit to get right, so it's often simpler to use a 3rd party library to write out the XML. For example, the XMLWriter in dom4j.

You can check out Tidy specification. its a spec released by w3c. Almost all recent languages have their own implementation.
rather than just replace or care only to < ,>, & just configure JTidy ( for java ) options and parse. this abstracts all the complication of Xml escape thing.
i have used both python , java and marklogic based tidy implementations. all solved my purposes