Develop Reference

How do I transfer my parsed array data from one class to another?

My program uses Picocli to parse XML data and store it in an ArrayList. For some reason, the information gets removed when I try to access it from another class.
I run the code below, and it shows the elements just fine:
public class SourceSentences {
static String source;
static ArrayList<String> sourceArray = new ArrayList<>();
public static void translate() throws ParserConfigurationException, IOException, SAXException {
String xmlFileLocation = "C:\\Users\\user\\Desktop\\exercise\\source.txml";
System.out.println("---------------");
System.out.println("Get Text From Source File: ");
DocumentBuilderFactory builderFactory = DocumentBuilderFactory.newInstance();
builderFactory.setFeature(XMLConstants.FEATURE_SECURE_PROCESSING, true);
//parse '.txml' file
DocumentBuilder builder = builderFactory.newDocumentBuilder();
Document document = builder.parse(new File(xmlFileLocation));
//...
document.getDocumentElement().normalize();
//specify tag in the '.txml' file and iterate
NodeList nodeList = document.getElementsByTagName("segment");
for (int i = 0; i < nodeList.getLength(); i++) {
//this is tag index of where line of el are
Node node = nodeList.item(i);
//check if actually a node
if (node.getNodeType() == Node.ELEMENT_NODE) {
//create a node object that will retrieve the element in the XML file
Element element = (Element) node;
//get the element from the specified node in nodeList
source = element.getElementsByTagName("source").item(0).getTextContent();
//check what it looks like
System.out.println(source);
//add to arraylist
sourceArray.add(source);
}
/*String[] arr = source.split("\\s");
System.out.println(Arrays.toString(arr));
System.out.println(Arrays.toString(arr));*/
}
//get its data type to make sure
System.out.println("data type: " + source.getClass().getSimpleName());
System.out.println(sourceArray);
}
}
So I try to access sourceArray from another class:
class getArrayElements extends SourceSentences{
public static void main(String[] args) {
System.out.println(SourceSentences.sourceArray);
}
}
and results in variables being [], thus not able to transfer data to another class.
Picocli setup snippet:
public class TranslateTXML implements Callable<String> {
#Option(names = "-f", description = " path to source txml file")
private String file;
#Option(names = "-o", description = "output path")
private String output;
public static void main(String... args) throws Exception {
int exitCode = new picocli.CommandLine(new TranslateTXML()).execute(args);
System.exit(exitCode);
}
public String call() throws Exception {
if (file != null) {
if (file.equals("C:\\Users\\gnier\\Desktop\\exercise\\source.txml")) {
sourceSent("C:\\Users\\gnier\\Desktop\\exercise\\source.txml");
System.out.println("source.txml data retrieved\n");
} else {
System.out.println("File \"source.txml\" not found. Check FileName and Directory.");
System.exit(2);
}
}
WriteSourceTranslatedToTXML.makeTranslated(System.out);
System.out.println("translated made");
System.out.println("------");
System.out.println("File \"translated.txml\" has been outputted to designated path");
}
}

The static context of the SourceSentences.main() is lost once you run the getArrayElements.main() method. The parsing of your XML data never happened as far as getArrayElements.main() was concerned.
You need to call the translate method from inside the getArrayElements' main function.
class getArrayElements extends SourceSentences {
public static void main(String[] args) throws ParserConfigurationException, IOException, SAXException {
SourceSentences.translate();
System.out.println(SourceSentences.sourceArray);
}
}

Can not populate List<Item> from XML nodes

I have an xml document to parse which have nested nodes I have tried in my way but unable to get job done as desired.
XML doc is
<Items>
<Item>
<MediumImage>
<URL>http://ecx.images-amazon.com/images/I/51l7DDD1qNL._SL160_.jpg</URL>
<Height Units="pixels">160</Height>
<Width Units="pixels">160</Width>
</MediumImage>
<Title>Fallout 4 Vault Dweller's Survival Guide Collector's Edition: Prima Official Game Guide</Title>
<OfferSummary>
<LowestNewPrice>
<Amount>1952</Amount>
</OfferSummary>
</Item>
.
.
.
</Items>
I have done to fetch Title node values as
private static NodeList fetchTitle(String requestUrl) {
NodeList nodeList = null;
try {
DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
DocumentBuilder db = dbf.newDocumentBuilder();
Document doc = db.parse(requestUrl);
nodeList = doc.getElementsByTagName("Title");
} catch (Exception e) {
System.out.println("Message is " + e.getCause() + "...." + e.getMessage());
throw new RuntimeException(e);
}
return nodeList;
}
and I print as in main() as
titleList = fetchTitle(requestUrl);
for (int i = 0; i < titleList.getLength(); i++) {
Node node = titleList.item(i);
if (node.getNodeType() == Node.ELEMENT_NODE) {
// do something with the current element
System.out.println(node.getNodeName());
System.out.println("Signed Title is \"" + node.getTextContent() + "\"");
System.out.println();
}
}
and Amount value from LowestNewPrice Node as
private static NodeList fetchPrice(String requestUrl) {
NodeList nodeList = null;
try {
DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
DocumentBuilder db = dbf.newDocumentBuilder();
Document doc = db.parse(requestUrl);
nodeList = doc.getElementsByTagName("LowestNewPrice");
} catch (Exception e) {
System.out.println("Message is " + e.getCause() + "...." + e.getMessage());
throw new RuntimeException(e);
}
return nodeList;
}
and I print as in main() as
priceList = fetchPrice(requestUrl);
for (int i = 0; i < priceList.getLength(); i++) {
Node node = priceList.item(i).getFirstChild();
if (node.getNodeType() == Node.ELEMENT_NODE) {
// do something with the current element
System.out.println(node.getNodeName());
System.out.println("Signed Price is \"" + node.getTextContent() + "\"");
System.out.println();
}
}
through above code I get all Title values first and then I get Amount values separately, but what I really want is to have a POJO class as
public class Item {
String title;
String price;
public String getTitle() {
return title;
}
public void setTitle(String title) {
this.title = title;
}
public String getPrice() {
return price;
}
public void setPrice(String price) {
this.price = price;
}
}
and add values to Item object using setTitle(), setPrice(), and return a List<Item>
any help please.

You might try this solution please.
Parse your data and add to List<Item> as :
public static Document fetchRequiredData(String src) {
Document doc = null;
DocumentBuilderFactory dbFactory = DocumentBuilderFactory.newInstance();
DocumentBuilder parser;
try {
parser = dbFactory.newDocumentBuilder();
doc= parser.parse(src);
} catch (ParserConfigurationException e) {
e.printStackTrace();
} catch (SAXException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
return doc;
}
public static List<Item> parseItemInfo(Document doc){
List<Item> items = new ArrayList<Item>();
NodeList itemNodeList = doc.getElementsByTagName("Item");
for (int i = 0; i < itemNodeList.getLength(); i++) {
Node titleNode = doc.getElementsByTagName("Title").item(i);
Node priceNode = doc.getElementsByTagName("LowestNewPrice").item(i).getFirstChild();
if (titleNode.getNodeType() == Node.ELEMENT_NODE || priceNode.getNodeType() == Node.ELEMENT_NODE ) {
Item item = new Item();
item.setDesc(titleNode.getTextContent());
item.setPrice(priceNode.getTextContent());
items.add(item);
}
}
return items;
}
now your List is ready to test in main() method as
public static void main(String[] args) {
List<Item> items = parseItemInfo(fetchRequiredData(requestUrl));
System.out.println("Printing List<Item> contents ...");
for (Item item : items) {
System.out.println("Title is " + item.getTitle());
System.out.println("Price is " + item.getPrice());
System.out.println();
}
}
Hope this one helps.

You can achieve that by using JAXBContext. First create Item class.
#XmlRootElement(name = "Items")
#XmlAccessorType(value = XmlAccessType.FIELD)
public class Items
{
#XmlElement(name = "Item")
private List<Item> item;
public void setItem(List<Item> itemList)
{
this.item = itemList;
}
public List<Item> getItem()
{
return this.item;
}
}
#XmlRootElement(name = "Item")
#XmlAccessorType(vallue = XmlAccessType.FIELD)
public class Item
{
#XmlElement(name = "MediumImage")
private MediumImage image;
#XmlElement(name = "Title")
private String title;
#XmlElement(name = "OfferSummary")
private OfferSummary summary;
getters();
setters();
}
#XmlRootElement(name = "MediumImage")
#XmlAccessorType(value = XmlAccessType.FIELD)
public class MediumImage
{
#XmlElement(name = "URL")
private String url;
....
}
#XmlRootElement(name = "OfferSummary")
#XmlAccessorType(value = XmlAccessType.FIELD)
public class OfferSummary
{
#XmlElement(name = "LowestNewPrice")
private LowestNewPrice lowestPrice;
....
}
Then from the main method use marshaller and unmarshaller method.
public static void main(String[] args)
{
File xmlFile = new File("file path");
JAXBContext context = JAXBContext.newInstance(Items.class);
//To get POJO from xml
Unmarshaller unmarshaller = context.createUnmarshaller();
Items items = (Items) unmarshaller.unmarshal(xmlFile);
}

Currently it seems that you're separating the prices and titles into 2 lists, if you want to store an item's price and title into a single Item object, you can do something like this:
public class Item {
public static void main(String[] args) {
ArrayList<Item> items = new ArrayList<Item>();
try {
DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
DocumentBuilder db = dbf.newDocumentBuilder();
Document doc = db.parse(new File("items.xml"));
NodeList itemElements = doc.getElementsByTagName("Item");
for (int i = 0; i < itemElements.getLength(); i++) {
Node itemElement = itemElements.item(i);
NodeList itemChildren = itemElement.getChildNodes();
Item item = new Item();
for (int j = 0; j < itemChildren.getLength(); j++) {
Node n = itemChildren.item(j);
if (n.getNodeName().equalsIgnoreCase("title")) {
item.setTitle(n.getTextContent());
} else if (n.getNodeName().equalsIgnoreCase("OfferSummary")) {
NodeList offerChildren = n.getChildNodes();
for (int k = 0; k < offerChildren.getLength(); k++) {
Node offerChild = offerChildren.item(k);
if (offerChild.getNodeName().equalsIgnoreCase("LowestNewPrice")) {
item.setPrice(offerChild.getTextContent());
}
}
}
}
items.add(item);
}
} catch (Exception e) {
e.printStackTrace();
}
System.out.println("items: " + items);
}
String title;
String price;
public String getTitle() {
return title;
}
public void setTitle(String title) {
this.title = title;
}
public String getPrice() {
return price;
}
public void setPrice(String price) {
this.price = price;
}
#Override
public String toString() {
return "Title: " + title + " Price: " + price;
}
}
What this does is to get all the <Item> elements from the XML and loop through them to get the item's title and price.

How can I omit some of my elements while serializing my object with SimpleXML?

It may be a basic question, but I could not manage to find a correct answer. Maybe it is an exceptional usage of SimpleXML.
In SimpleXML (java) I want to read some attributes of an object from XML and then save the Object again to another XML without writing those attributes.
I want to read "Question" object from this XML definition:
<question>
<questionID>0</questionID>
<category>tarih</category>
<difficultyLevel>80</difficultyLevel>
<text>Tarihte gelmiş geçmiş en büyük sınırlara ulaşan imparatorluk, aşağıdakilerden hangisidir?</text>
<alternatives length="4">
<string>Britanya</string>
<string>Roma</string>
<string>Moğol</string>
<string>Osmanlı</string>
</alternatives>
<answerID>0</answerID>
And Serialize it back as follows by eliminating the "alternatives" fields:
<question>
<questionID>0</questionID>
<category>tarih</category>
<difficultyLevel>80</difficultyLevel>
<text>Tarihte gelmiş geçmiş en büyük sınırlara ulaşan imparatorluk, aşağıdakilerden hangisidir?</text>
<answerID>0</answerID>
</question>
Is this possible?
Edit: The java class definition of "Question":
public class Question {
public final static int N_POSSIBLE_ANSWERS=4;
public final static String[] ALTERNATIVE_CAPTIONS = {"A","B","C","D"};
// Attributes
#Element
public int questionID;
#Element
public String category;
#Element
public int difficultyLevel;
#Element
public String text;
#ElementArray
private String[] alternatives;
#Element(required=false)
private int answerID = -1;
// State variables
private int nAddedAlternatives=0;
public String[] getAlternatives() {
return alternatives;
}
public void addAlternative(String alternative){
if(alternatives == null){
alternatives = new String[N_POSSIBLE_ANSWERS];
}
alternatives[nAddedAlternatives] = alternative;
nAddedAlternatives++;
}
public void clearAlternatives(){
nAddedAlternatives = 0;
alternatives = null;
}
public String getAlternative(int i){
//String result = ALTERNATIVE_CAPTIONS[i];
//result += ": ";
String result = alternatives[i];
return result;
}
public int getAnswer(){
return answerID;
}
public void setAnswer(int answer){
answerID = answer;
}
}
The ElementArray defined as "alternatives" is the interest point of this question.
Best regards,
fercis

Please use the below method to convert that
public static void convert(InputStream inputStream,OutputStream outputStream,List<String> result) {
try {
DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
factory.setIgnoringElementContentWhitespace(true);
DocumentBuilder builder = factory.newDocumentBuilder();
Document document = builder.parse(inputStream);
if(inputStream != null)
inputStream.close();
NodeList childNodes = document.getChildNodes().item(0).getChildNodes();
Document writeDoc = builder.newDocument();
Element rootElement = writeDoc.createElement(document.getChildNodes().item(0).getNodeName());
for (int i = 0; i < childNodes.getLength(); i++) {
Node item = childNodes.item(i);
if(result.contains(item.getNodeName())) {
System.out.println("Skipped ...");
continue;
}
Node node = item.cloneNode(true);
writeDoc.adoptNode(node);
rootElement.appendChild(node);
}
writeDoc.appendChild(rootElement);
TransformerFactory transformerFactory = TransformerFactory.newInstance();
Transformer transformer = transformerFactory.newTransformer();
DOMSource source = new DOMSource(writeDoc);
transformer.transform(source, new StreamResult(outputStream));
} catch (Exception e) {
e.printStackTrace();
}
}
This is the method which take the input as a InputStream, will return result in OutPutStream, will accept List of String that need to be filtered.

How can I parse long strings from an online xml file in Android application?

I want to parse a very long string from an xml file. You can see the xml file here.
If you visit the above file, there is a "description" tag from which I want to parse the string. When there is a short short string, say 3-lines or 4-lines string in the "description" tag, then my parser(Java SAX parser) easily parse the string but, when the string is hundreds of lines then my parser cannot parse the string. You can check my code that I am using for the parsing and please let me know where I am going wrong in this regard. Please help me in this respect I would be very thankful to you for this act of kindness.
Here is the parser GetterSetter class
public class MyGetterSetter
{
private ArrayList<String> description = new ArrayList<String>();
public ArrayList<String> getDescription()
{
return description;
}
public void setDescription(String description)
{
this.description.add(description);
}
}
Here is the parser Handler class
public class MyHandler extends DefaultHandler
{
String elementValue = null;
Boolean elementOn = false;
Boolean item = false;
public static MyGetterSetter data = null;
public static MyGetterSetter getXMLData()
{
return data;
}
public static void setXMLData(MyGetterSetter data)
{
MyHandler.data = data;
}
public void startDocument() throws SAXException
{
data = new MyGetterSetter();
}
public void endDocument() throws SAXException
{
}
public void startElement(String namespaceURI, String localName,String qName, Attributes atts) throws SAXException
{
elementOn = true;
if (localName.equalsIgnoreCase("item"))
item = true;
}
public void endElement(String namespaceURI, String localName, String qName) throws SAXException
{
elementOn = false;
if(item)
{
if (localName.equalsIgnoreCase("description"))
{
data.setDescription(elementValue);
Log.d("--------DESCRIPTION------", elementValue +" ");
}
else if (localName.equalsIgnoreCase("item")) item = false;
}
}
public void characters(char ch[], int start, int length)
{
if (elementOn)
{
elementValue = new String(ch, start, length);
elementOn = false;
}
}
}

Use the org.w3c.dom package.
public static void main(String[] args) {
try {
URL url = new URL("http://www.aboutsports.co.uk/fixtures/");
DocumentBuilderFactory dbFactory = DocumentBuilderFactory.newInstance();
DocumentBuilder dBuilder = dbFactory.newDocumentBuilder();
Document doc = dBuilder.parse(url.openStream());
NodeList list = doc.getElementsByTagName("item"); // get <item> nodes
for (int i = 0; i < list.getLength(); i++) {
Node item = list.item(i);
NodeList descriptions = ((Element)item).getElementsByTagName("description"); // get <description> nodes within an <item>
for (int j = 0; j < descriptions.getLength(); j++) {
Node description = descriptions.item(0);
System.out.println(description.getTextContent()); // print the text content
}
}
} catch (Exception e) {
e.printStackTrace();
}
}
XPath in java is also great for extracting bits from XML documents. Here's an example.
You would use a XPathExpression like /item/description. When you would evaluate it on the XML InputStream, it would return a NodeList like above with all the <description> elements within a <item> element.
If you wanted to do it your way, with a DefaultHandler, you would need to set and unset flags so you can check if you are in the body of a <document> element. The code above probably does something similar internally, hiding it from you. The code is available in java, so why not use it?

Java DOM XML Parsing

So I have an XML file in the format:
<projectlist>
<project>
<name>test</name>
<type>deploy</type>
<environment>dev</environment>
<server>test01</server>
<server>test02</server>
<server>test03</server>
</project>
</projectlist>
I'm trying to parse this file and build an object that I can populate a JListBox with the names and a radiobutton group with the different servers, however each project consists of a different amount of servers. How do I iterate the nodes/childnodes to build the object with multiple servers. Here is snippets of the code I'm using borrowed from a website and some from me and I'm not very good at coding yet so bear with me please. When I debug it starts to parse & build the object but once it gets to the server names it prints a null pointer exception so I'm doing something totally wrong.
public class XMLParser {
public Project currentProject = new Project();
public void parseXML() throws Exception {
try {
File file = new File("c:\\projectlist.xml");
DocumentBuilderFactory dbFactory = DocumentBuilderFactory.newInstance();
DocumentBuilder dBuilder = dbFactory.newDocumentBuilder();
Document doc = dBuilder.parse(file);
doc.getDocumentElement().normalize();
NodeList nList = doc.getElementsByTagName("project");
for (int temp = 0; temp < nList.getLength(); temp++) {
Node nNode = nList.item(temp);
if (nNode.getNodeType() == Node.ELEMENT_NODE) {
Element eElement = (Element) nNode;
currentProject.SetAppName(getTagValue("name", eElement));
currentProject.SetType(getTagValue("type", eElement));
currentProject.SetEnvironment(getTagValue("environment", eElement));
currentProject.SetServerName(getTagValue("server", eElement));
}
}
} catch (Exception e) {
e.printStackTrace();
}
}
private static String getTagValue(String sTag, Element eElement) {
NodeList nlList = eElement.getElementsByTagName(sTag).item(0).getChildNodes();
Node nValue = (Node) nlList.item(0);
return nValue.getNodeValue();
}
public final class Project {
protected String AppName = null;
protected String Type = null;
protected List<String> ServerNames = null;
protected String Environment = null;
public void SetAppName(String AppName) {
this.AppName = AppName;
}
public void SetType(String DeployType) {
this.Type = DeployType;
}
public void SetServerName(String ServerName) {
this.ServerNames.add(ServerName);
}
public void SetEnvironment(String Environment) {
this.Environment = Environment;
}
public String getAppName() {
return AppName;
}
public String getType() {
return Type;
}
public List<String> getServerName() {
return ServerNames;
}
public String getEnvironment() {
return Environment;
}
}

Your exception is being caused because you didn't initialize ServerNames in your Project class. Try to initialize it as follows and rerun:
final protected List<String> ServerNames = new ArrayList<String>();

If your xml was created using an xsd schema, you could instead use JAXB to create classes for it, using the xjc tool. That should make your life a bit easier.