Java DOM parser API has methods, interfaces and classes to create XML documents. Using this API, we can create XML documents from the scratch through our Java applications. The createElement() method creates new elements and the appendChild() method appends the created elements to already existing elements.
Create XML Using Java DOM Parser
We can create an XML document in Java using DOM parser through following steps −
- Step 1: Creating a DocumentBuilder Object
- Step 2: Create a new Document
- Step 3: Creating the root element
- Step 4: Appending elements to the root element
- Step 5: Writing the content into XML file
- Step 6: Testing the output using console
Refer this page for step 1.
Step2: Create a new Document
Using DocumentBuilder object created in the above step, create a new document with newDocument() function.
Document doc = dBuilder.newDocument();Step3: Creating the root element
Every XML document should possess a single root element , which is also called a parent element. We can create the root element using createElement() method and append it to the document created in the previous step.
Element rootElement = doc.createElement("root");
doc.appendChild(rootElement);Step 4: Appending elements to the root element
Inside the root element, we can create any number of child elements and append them the same way we appended root element to the document. To write text content inside an element, we can use createTextNode() method. We can also create attributes for elements using createAttribute() method.
Element child = doc.createElement("child");
rootElement.appendChild(child);
child.appendChild(doc.createTextNode("text_content_here"));Attr attr = doc.createAttribute("child");Step 5: Writing the content into XML file
After building the elements inside the document with their corresponding attributes, we need to write this content into an XML file by creating Tranformer object, which in-turn transforms our source document into StreamResult and stores it in the specified file path with the given name.
TransformerFactory transformerFactory =TransformerFactory.newInstance();Transformer transformer = transformerFactory.newTransformer();DOMSource source =newDOMSource(doc);StreamResult result =newStreamResult(newFile("filepath:\\new.xml"));
transformer.transform(source, result);Step 6: Testing the output using console
We can test our XML file by printing it on the console. This is an optional step.
StreamResult consoleResult =newStreamResult(System.out);
transformer.transform(source, consoleResult);Creating Basic XML File
To create a document element, we use the method createElement(“element_name”). This method takes element name as an argument and returns a new Element object.
After getting the new Element object, we can use appendChild(Element) method to append this Element object to the document. This method is also used to append an element to another element (creating child elements).
cars.xml
We want to create the following xml file with the name “cars.xml” in D drive.
<cars><supercars>Ferrari</supercars></cars>CreateXMLDemo.java
In the following code, we have created one root element with name “cars” and appended one child element with name “supercars”. We have also added text content to supercars element.
importjavax.xml.parsers.DocumentBuilderFactory;importjavax.xml.parsers.DocumentBuilder;importjavax.xml.transform.Transformer;importjavax.xml.transform.TransformerFactory;importjavax.xml.transform.dom.DOMSource;importjavax.xml.transform.stream.StreamResult;importorg.w3c.dom.Document;importorg.w3c.dom.Element;importjava.io.File;publicclassCreateXMLDemo{publicstaticvoidmain(String argv[]){try{//Creating a DocumentBuilder ObjectDocumentBuilderFactory dbFactory =DocumentBuilderFactory.newInstance();DocumentBuilder dBuilder = dbFactory.newDocumentBuilder();//Create a new DocumentDocument doc = dBuilder.newDocument();//Creating the root elementElement rootElement = doc.createElement("cars");
doc.appendChild(rootElement);//Appending elements to the root elementElement supercar = doc.createElement("supercars");
rootElement.appendChild(supercar);
supercar.appendChild(doc.createTextNode("Ferrari"));//writing the content into XML fileTransformerFactory transformerFactory =TransformerFactory.newInstance();Transformer transformer = transformerFactory.newTransformer();DOMSource source =newDOMSource(doc);StreamResult result =newStreamResult(newFile("D:\\cars.xml"));
transformer.transform(source, result);//Output to console for testingStreamResult consoleResult =newStreamResult(System.out);
transformer.transform(source, consoleResult);}catch(Exception e){e.printStackTrace();}}}Output
For testing, we have printed the document output on the console.
<?xml version="1.0" encoding="UTF-8" standalone="no"?><cars><supercars>Ferrari</supercars></cars>Learn Java in-depth with real-world projects through our Java certification course. Enroll and become a certified expert to boost your career.
Creating XML File with Attributes
Attributes can be created to an Element using the method, createAttribute(“Attribute_name”). This method of Document interface takes name of the attribute as an argument and returns the Attr object. The setValue(“value”) method is used to set the value of the attribute.
Now, to set this attribute node to the Element, we use setAttributeNode(Attr) method with the Element object to which we need to set this attribute.
newcars.xml
We need to create the following “newcars.xml” in D drive.
<cars><supercars company="Ferrari"><carname type="formula one">Ferrari 101</carname><carname type="sports">Ferrari 202</carname></supercars></cars>CreateXMLAttributeDemo.java
We have created two carname elements for supercars element. Also, using setAttributeNode() method, we have added two attributes for each of the carname elements.
importjavax.xml.parsers.DocumentBuilderFactory;importjavax.xml.parsers.DocumentBuilder;importjavax.xml.transform.Transformer;importjavax.xml.transform.TransformerFactory;importjavax.xml.transform.dom.DOMSource;importjavax.xml.transform.stream.StreamResult;importorg.w3c.dom.Attr;importorg.w3c.dom.Document;importorg.w3c.dom.Element;importjava.io.File;publicclassCreateXMLAttributeDemo{publicstaticvoidmain(String argv[]){try{//Creating a DocumentBuilder ObjectDocumentBuilderFactory dbFactory =DocumentBuilderFactory.newInstance();DocumentBuilder dBuilder = dbFactory.newDocumentBuilder();//Creating a new DocumentDocument doc = dBuilder.newDocument();//Creating the root elementElement rootElement = doc.createElement("cars");
doc.appendChild(rootElement);//Appending sub element to the root elementElement supercar = doc.createElement("supercars");
rootElement.appendChild(supercar);//Setting attribute to the sub elementAttr attr = doc.createAttribute("company");
attr.setValue("Ferrari");
supercar.setAttributeNode(attr);//Adding First child element to sub elementElement carname = doc.createElement("carname");Attr attrType = doc.createAttribute("type");
attrType.setValue("formula one");
carname.setAttributeNode(attrType);
carname.appendChild(doc.createTextNode("Ferrari 101"));
supercar.appendChild(carname);//Adding second child element to sub elementElement carname1 = doc.createElement("carname");Attr attrType1 = doc.createAttribute("type");
attrType1.setValue("sports");
carname1.setAttributeNode(attrType1);
carname1.appendChild(doc.createTextNode("Ferrari 202"));
supercar.appendChild(carname1);//writing the content into XML fileTransformerFactory transformerFactory =TransformerFactory.newInstance();Transformer transformer = transformerFactory.newTransformer();DOMSource source =newDOMSource(doc);StreamResult result =newStreamResult(newFile("D:\\newcars.xml"));
transformer.transform(source, result);//Output to console for testingStreamResult consoleResult =newStreamResult(System.out);
transformer.transform(source, consoleResult);}catch(Exception e){ e.printStackTrace();}}}Output
For testing, we have printed the document output on the console.
<?xml version="1.0" encoding="UTF-8" standalone="no"?><cars><supercars company="Ferrari"><carname type="formula one">Ferrari 101</carname><carname type="sports">Ferrari 202</carname></supercars></cars>
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