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Jacskon XML serialization of a list

EDIT: I am trying to serialise to XML markup from Java objects.
I am struggling to serialise some XML from a List of size N of Integers using Jackson.
I want to output the following XML from a list of integers of variable length [9, 2, ... , 7].
<tagName>
<thing1>9</thing1>
<thing2>2</thing2>
...
<thingN>7</thingN>
<tagName>
I can't find any resource on here for dealing with deserialising lists.
The closest I have managed to get is
#JacksonXmlProperty(localName = "thing")
private List<Integer> thingList;
And I can't figure out how to add a counter to the local name for each member of the list.
Any help would be appreciated, thank you!

Ok Now I got your problem. So We I tried It with Jsoup library and find below code snippet for your work.
public static void main(String[] args) {
int [] array={1,2,3,4,5};
TagName name = new TagName();
//initialize the TagName object
for (int a=0;a<array.length;a++) {
name.setThingList(array[a]);
}
XmlMapper xmlMapper = new XmlMapper();
try {
//get object as a string
String value = xmlMapper.writeValueAsString(name);
//First you need to parse the xml
Document doc = Jsoup.parse(value, "", Parser.xmlParser());
//get tagname object
Element tagname = doc.getElementsByTag("tagname").first();
//get tagname's children which are thing
Elements childs = tagname.children();
for (int a = 0; a < childs.size(); ) {
//rename their tagname
childs.get(a).tagName("thing" + ++a);
}
System.out.println(tagname);
} catch (IOException e) {
e.printStackTrace();
}
}
<tagname>
<thing1>
1
</thing1>
<thing2>
2
</thing2>
<thing3>
3
</thing3>
<thing4>
4
</thing4>
<thing5>
5
</thing5>
</tagname>
#JacksonXmlRootElement(localName = "xml")
public class TagName {
public ArrayList<Integer> getThingList() {
return thingList;
}
public void setThingList(Integer thing) {
this.thingList.add(thing);
}
#JacksonXmlElementWrapper(localName = "tagname")
#JacksonXmlProperty(localName = "thing")
private ArrayList<Integer> thingList = new ArrayList<>();
}

Play Framework IF statement and FOR loop

I am new to MVC and following this link I have a search page for resulting pdf metadatas by using Solr. My if statement and for loop in html side do not work
Searching.java in models folder:
public class Searching {
public String q;
public String outputTitle;
public String outputAuthor;
public String outputContent;
public String outputPage;
public String outputPath;
}
search function in Application.java:
final static Form<Searching> searchForm = form(Searching.class);
final static List<Searching> searchList = new ArrayList<Searching>();
public static Result search() {
Form<Searching> filledForm = searchForm.bindFromRequest();
Searching searched = filledForm.get();
....(database connection lines)
QueryResponse response = solr.query(query);
SolrDocumentList results = response.getResults();
if(results.isEmpty())
System.out.println("SEARCH NOT FOUND");
else {
for (int i = 0; i < results.size(); ++i) {
searched.outputTitle = (String)results.get(i).getFirstValue("title");
searched.outputAuthor = (String)results.get(i).getFirstValue("author");
searched.outputPage =results.get(i).getFirstValue("pageNumber").toString();
searched.outputContent = (String)results.get(i).getFirstValue("content");
searched.outputPath = (String)results.get(i).getFirstValue("path");
searchList.add(searched);
}
System.out.println("\nresults.getNumFound(): "+ searched.outputFound);
System.out.println("results.size(): "+results.size());
}
return play.mvc.Results.ok(search.render(searched, searchForm, searchList));
}
search.scala.html
#(searched: Searching, searchForm: Form[Searching], searchList: List[Searching])
.. some buttons,a search bar...
#if(searchList.isEmpty()) {
<h1>Error</h1>
} else {
#for(search <- searchList) {
<ul>Title: #search.outputTitle</ul>
<ul>Author: #search.outputAuthor <a href="#search.outputPath" download>Download PDF</a></ul>
<ul>Number of Page(s): #search.outputPage</ul>
}
}
Java code works well. I can see outputs on the terminal, but my html side has problem and it shows one book many times according to size of searchList

I am posting the answer explicitly even though I was able to help the OP in the chat - maybe somebody else is running into such problem but did not check the chat:
The problem is even though you have the line in the for-loop you are still using the same searched variable. What you have to do is to reinitialize the variable when entering the loop. Something like:
for (...) {
searched = new Searching();
searched.outputTitle = (String)results.get(i).getFirstValue("title");
....
searchList.add(searched);
}
This solves the problem with the duplicates and everything is fine now.

Has XMLUnit an Output of XPathes with Namespaces?

For my Java program im using XMLUnit 1.5, wich compares two XML-Files (with Namespaces). But the XPathes, I get, do not contain any Namespaces. How I can tell XMLUnit todo that? Is that possible?
Here is my code:
control = new FileReader(file1);
test = new FileReader(file2);
list = new ArrayList<Unterschied>();
Diff diff;
diff = new Diff(control, test);
diff.overrideElementQualifier(new ElementNameAndAttributeQualifier());
if (diff.similar())
{
MessageDialog.openInformation(null, "Info", "Similar");
}
else if (!diff.similar())
{
DetailedDiff detDiff = new DetailedDiff(diff);
detDiff.overrieElementQualifier(new ElementNameAndAttributeQualifier());
#SuppressWarnings("unchecked")
List<Object> differences = detDiff.getAllDifferences();
for (Object object : differences)
{
Difference difference = (Difference) object;
if (!difference.isRecoverable() && !difference.getDescription().contains("number of child nodes"))
{
controlXPath = difference.getControlNodeDetail().getXpathLocation(); // without Namespaces!
controlValue = difference.getControlNodeDetail().getValue();
testXPath = difference.getTestNodeDetail().getXpathLocation(); // without Namespaces!
testValue = difference.getTestNodeDetail().getValue();
list.add(new Unterschied(controlOrt, controlWert, testOrt, testWert));
}
}
Later in my program I evaluating these XPathes for getting the correct position of this node. With these position I select the appropriate text in the editor, so that the user can see the Difference.
My code for evaluating:
public void evaluateXPath(String xp, Node node) {
XPath newXPath = new XPathFactoryImpl().newXPath();
XPathExpression xpExp = newXPath.compile(xpath);
NodeList nodeList = (NodeList) xpExp.evaluate(node, XPathConstants.NODESET);
int length = nodeList.getLength();
for (int i=0; i < length; i++) {
IDOMNode iDOMnode = (IDOMNode) nodeList.item(i);
textEditor.selectAndReveal(iDOMnode.getStartOffset(), iDOMnode.getEndOffset()-iDOMnode.getStartOffset());
}
}
Thanks for your help and sorry for my bad english! ;)

No, XMLUnit 1.x will only return plain XPath without any namespace indication at all.
XMLUnit 2.x (under development) will return XPaths using prefixes for namespaces that can be configured per NS-URI.

Android - Reading XML issues

I've got an app that consumes a .NET web service which returns an XML string of data. I'm trying to read this XML and insert it into the local SQLite DB but I'm having some trouble. Here's a sample of the xml:
<?xml version="1.0" encoding="utf-8" ?>
<string xmlns="RemoteWebService"><OpenIssues> <Table> <IssueID>15351</IssueID> <IssueSummary>Computer keeps crashing. This continues to be a problem</IssueSummary> <LocationName>West Side</LocationName> <Status>WIP</Status> <CustomerID>89755</CustomerID> <CustomerName>West Side Computers</CustomerName> <CustomerShortName>WSC</CustomerShortName> <Notes /> <STATUS1>Work In Progress</STATUS1> <SubmittedBy>WSC - Tom Johns</SubmittedBy> <EQ_Replaced>true</EQ_Replaced></Table> </OpenIssues></string>
Using DOM, I'm trying to parse the results like so:
private void GetLatestData(String response) throws ParserConfigurationException, SAXException, IOException{
DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
DocumentBuilder db = dbf.newDocumentBuilder();
Document doc = db.parse(new InputSource(new StringReader(response)));
//Normalize the document.
doc.getDocumentElement().normalize();
//Get Root Node.
NodeList nodeList = doc.getElementsByTagName("Table");
Node node = nodeList.item(0);
//Get Child Nodes.
for(int i = 0; i < node.getChildNodes().getLength(); i++){
IssueInfo issue = new IssueInfo();
Node tempNode = node.getChildNodes().item(i);
if(tempNode.getNodeName().equalsIgnoreCase("IssueID")){
issue.setIssueNumber(Long.parseLong(tempNode.getTextContent()));
}
if(tempNode.getNodeName().equalsIgnoreCase("IssueSummary")){
issue.setIssueNumber(Long.parseLong(tempNode.getTextContent()));
}
if(issue.getIssueNumber() > 0 && issue.getIssueSummary() != null){
creator = new IssueInfoCreator(this, DBVersion);
creator.open();
creator.InsertIssue(issue.getIssueNumber(), DateFormat.getDateInstance().format(new Date()), issue.getIssueSummary());
creator.close();
}
}
}
When I run it through the debugger, it gets "IssueID" just fine but how can I get it to pickup the next node "IssueSummary" right after that so I can insert the data at once? It seems like I need another loop somewhere, just not too sure where though.

If I understand your question correctly, this is what you may need to do.
Node node = nodeList.item(0);
Returns
<Table>
<IssueID>15351</IssueID>
<IssueSummary>Computer keeps crashing. This continues to be a problem</IssueSummary>
<Notes />
</Table>
node.getChildNodes().getLength();
Returns 3.
IssueInfo issue = new IssueInfo();
// Go through each child and find out node name and populate it.
for(int i = 0; i < node.getChildNodes().getLength(); i++){
Node tempNode = node.getChildNodes().item(i);
if(tempNode.getNodeName().equalsIgnoreCase("IssueID")){
issue.setIssueNumber(Long.parseLong(tempNode.getTextContent()));
}
if(tempNode.getNodeName().equalsIgnoreCase("IssueSummary")){
issue.setIssueNumber(Long.parseLong(tempNode.getTextContent()));
}
}
Move if logic out of the loop.
if(issue.getIssueNumber() > 0 && issue.getIssueSummary() != null){
creator = new IssueInfoCreator(this, DBVersion);
creator.open();
creator.InsertIssue(issue.getIssueNumber(), DateFormat.getDateInstance().format(new Date()), issue.getIssueSummary());
creator.close();
}

Seems like a simple DOM traversing issue.
If you can guarantee the next node is the summary, you could try using the getNextSibling() method for nodes
I modified your code so I could call it without using your classes. This is the code I used:
private static void GetLatestData(String response) {
try{
DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
/* the following 2 lines help you eliminate whitespace
from your xml DOM tree */
dbf.setValidating(true);
dbf.setIgnoringElementContentWhitespace(true);
DocumentBuilder db = dbf.newDocumentBuilder();
DocumentBuilder db = dbf.newDocumentBuilder();
Document doc = db.parse(new InputSource(new StringReader(response)));
//Normalize the document.
doc.getDocumentElement().normalize();
//Get Root Node.
NodeList nodeList = doc.getElementsByTagName("Table");
Node node = nodeList.item(0);
long issueNumber;
String summary;
//Get Child Nodes.
for(int i = 0; i < node.getChildNodes().getLength(); i++){
Node tempNode = node.getChildNodes().item(i);
if(tempNode.getNodeName().equalsIgnoreCase("IssueID")){
issueNumber = (Long.parseLong(tempNode.getTextContent()));
Node summaryNode = tempNode.getNextSibling();
summary = summaryNode.getTextContent();
System.out.println(String.format("Issue # %d, Summary: %s" , issueNumber,summary));
}
}
}catch(Exception exception){
exception.printStackTrace();
}
}
and I call it like this:
GetLatestData("<OpenIssues> " +
"<Table> " +
"<IssueID>15351</IssueID>" +
"<IssueSummary>Computer keeps crashing. This continues to be a problem</IssueSummary> " +
"<Notes />" +
"</Table></OpenIssues> ");
from a simple Java class. It's working all right for me, at least. It prints out:
Issue # 15351, Summary: Computer keeps crashing. This continues to be a problem

*smacks forehead*
issue will never have more than one value set, as it's created anew for each child node.
Just swap the two lines to create issue only once:
IssueInfo issue = new IssueInfo();
for(int i = 0; i < node.getChildNodes().getLength(); i++){
...
You should probably move the final if outside the for too, so it's not executed more than once.
AND you'll need to actually set the summary in the second if not. You're setting the 'issue number' twice.

Finally found the resolution to this with the help of my coworker and some digging around. It should be noted that we changed the WebService that returned a string from DataSet.GetXml() to an XmlDocument.InnerXml. This removed the spaces in between the nodes and then we were able to move forward from there. Here's the final code we used:
public void GetLatestData(SoapPrimitive xml)throws ParserConfigurationException, SAXException, IOException{
//get the factory
DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
//Using factory get an instance of document builder
DocumentBuilder db = dbf.newDocumentBuilder();
Document doc;
//parse using builder to get DOM representation of the XML file
InputSource is = new InputSource(new StringReader(xml.toString()));
doc = db.parse(is);
//Clear out Issues table first.
creator = new IssueInfoCreator(this, DBVersion);
creator.open();
creator.ClearIssueTable();
creator.close();
NodeList nodes = doc.getElementsByTagName("Table");
for(int i = 0; i < nodes.getLength(); i++) {
IssueInfo issue = new IssueInfo();
Element e = (Element)nodes.item(i);
issue.setIssueNumber(Long.parseLong(XMLfunctions.getValue(e, "IssueID")));
issue.setIssueSummary(XMLfunctions.getValue(e, "IssueSummary"));
issue.setDateReceived(DateFormat.format("MM/dd/yyyy hh:mm:ss", System.currentTimeMillis()).toString());
if(issue.getIssueNumber() > 0 && issue.getIssueSummary() != null){
creator = new IssueInfoCreator(this, DBVersion);
creator.open();
creator.InsertIssue(issue.getIssueNumber(), issue.getDateReceived(), issue.getIssueSummary());
creator.close();
}
}
}
And here is the getValue method of the XMLfuntions class:
public static String getValue(Element item, String str) {
NodeList n = item.getElementsByTagName(str);
return XMLfunctions.getElementValue(n.item(0));
}
public final static String getElementValue( Node elem ) {
Node kid;
if( elem != null){
if (elem.hasChildNodes()){
for( kid = elem.getFirstChild(); kid != null; kid = kid.getNextSibling() ){
if( kid.getNodeType() == Node.TEXT_NODE ){
return kid.getNodeValue();
}
}
}
}
return "";
}
Definately not taking credit for this, I found it here:
Programmer XR and modified it to my needs.
Hopefully this will help other people out!

Speeding up xpath

I have a 1000 entry document whose format is something like:
<Example>
<Entry>
<n1></n1>
<n2></n2>
</Entry>
<Entry>
<n1></n1>
<n2></n2>
</Entry>
<!--and so on-->
There are more than 1000 Entry nodes here. I am writing a Java program which basically gets all the node one by one and do some analyzing on each node. But the problem is that the retrieval time of the nodes increases with its no. For example it takes 78 millisecond to retrieve the first node 100 ms to retrieve the second and it keeps on increasing. And to retrieve the 999 node it takes more than 5 second. This is extremely slow. We would be plugging this code to XML files which have even more than 1000 entries. Some like millions. The total time to parse the whole document is more than 5 minutes.
I am using this simple code to traverse it. Here nxp is my own class which has all the methods to get nodes from xpath.
nxp.fromXpathToNode("/Example/Entry" + "[" + i + "]", doc);
and doc is the document for the file. i is the no of node to retrieve.
Also when i try something like this
List<Node> nl = nxp.fromXpathToNodes("/Example/Entry",doc);
content = nl.get(i);
I face the same problem.
Anyone has any solution on how to speed up the tretirival of the nodes, so it takes the same amount of time to get the 1st node as well as the 1000 node from the XML file.
Here is the code for xpathtonode.
public Node fromXpathToNode(String expression, Node context)
{
try
{
return (Node)this.getCachedExpression(expression).evaluate(context, XPathConstants.NODE);
}
catch (Exception cause)
{
throw new RuntimeException(cause);
}
}
and here is the code for fromxpathtonodes.
public List<Node> fromXpathToNodes(String expression, Node context)
{
List<Node> nodes = new ArrayList<Node>();
NodeList results = null;
try
{
results = (NodeList)this.getCachedExpression(expression).evaluate(context, XPathConstants.NODESET);
for (int index = 0; index < results.getLength(); index++)
{
nodes.add(results.item(index));
}
}
catch (Exception cause)
{
throw new RuntimeException(cause);
}
return nodes;
}
and here is the starting
public class NativeXpathEngine implements XpathEngine
{
private final XPathFactory factory;
private final XPath engine;
/**
* Cache for previously compiled XPath expressions. {#link XPathExpression#hashCode()}
* is not reliable or consistent so use the textual representation instead.
*/
private final Map<String, XPathExpression> cachedExpressions;
public NativeXpathEngine()
{
super();
this.factory = XPathFactory.newInstance();
this.engine = factory.newXPath();
this.cachedExpressions = new HashMap<String, XPathExpression>();
}

Try VTD-XML. It uses less memory than DOM. It is easier to use than SAX and supports XPath. Here is some sample code to help you get started. It applies an XPath to get the Entry elements and then prints out the n1 and n2 child elements.
final VTDGen vg = new VTDGen();
vg.parseFile("/path/to/file.xml", false);
final VTDNav vn = vg.getNav();
final AutoPilot ap = new AutoPilot(vn);
ap.selectXPath("/Example/Entry");
int count = 1;
while (ap.evalXPath() != -1) {
System.out.println("Inside Entry: " + count);
//move to n1 child
vn.toElement(VTDNav.FIRST_CHILD, "n1");
System.out.println("\tn1: " + vn.toNormalizedString(vn.getText()));
//move to n2 child
vn.toElement(VTDNav.NEXT_SIBLING, "n2");
System.out.println("\tn2: " + vn.toNormalizedString(vn.getText()));
//move back to parent
vn.toElement(VTDNav.PARENT);
count++;
}

The correct solution is to detach the node right after you call item(i), like so:
Node node = results.item(index)
node.getParentNode().removeChild(node)
nodes.add(node)
See XPath.evaluate performance slows down (absurdly) over multiple calls

I had similar issue with the Xpath Evaluation , I tried using CachedXPathAPI’s which is faster by 100X than the XPathApi’s which was used earlier.
more information about this Api is provided here :
http://xml.apache.org/xalan-j/apidocs/org/apache/xpath/CachedXPathAPI.html
Hope it helps.
Cheers,
Madhusudhan

If you need to parse huge but flat documents, SAX is a good alternative. It allows you to handle the XML as a stream instead of building a huge DOM. Your example could be parsed using a ContentHandler like this:
import org.xml.sax.Attributes;
import org.xml.sax.SAXException;
import org.xml.sax.ext.DefaultHandler2;
public class ExampleHandler extends DefaultHandler2 {
private StringBuffer chars = new StringBuffer(1000);
private MyEntry currentEntry;
private MyEntryHandler myEntryHandler;
ExampleHandler(MyEntryHandler myEntryHandler) {
this.myEntryHandler = myEntryHandler;
}
#Override
public void characters(char[] ch, int start, int length)
throws SAXException {
chars.append(ch);
}
#Override
public void endElement(String uri, String localName, String qName)
throws SAXException {
if ("Entry".equals(localName)) {
myEntryHandler.handle(currentEntry);
currentEntry = null;
}
else if ("n1".equals(localName)) {
currentEntry.setN1(chars.toString());
}
else if ("n2".equals(localName)) {
currentEntry.setN2(chars.toString());
}
}
#Override
public void startElement(String uri, String localName, String qName,
Attributes atts) throws SAXException {
chars.setLength(0);
if ("Entry".equals(localName)) {
currentEntry = new MyEntry();
}
}
}
If the document has a deeper and more complex structure, you're going to need to use Stacks to keep track of the current path in the document. Then you should consider writing a general purpose ContentHandler to do the dirty work and use with your document type dependent handlers.

What kind of parser are you using?
DOM pulls the whole document in memory - once you pull the whole document in memory then your operations can be fast but doing so in a web app or a for loop can have an impact.
SAX parser does on demand parsing and loads nodes as and when you request.
So try to use a parser implementation that suits your need.

Use the JAXEN library for xpaths:
http://jaxen.codehaus.org/