Adding XML comments to a marshaling file using JAXBContext

Question

I am collecting objects in an XML file. How to add comments to this XML file

ObjectFactory factory = new ObjectFactory(); JAXBContext jc = JAXBContext.newInstance(Application.class); Marshaller jaxbMarshaller = jc.createMarshaller(); jaxbMarshaller.marshal(application, localNewFile); jaxbMarshaller.marshal(application, System.out); 

so that some think how

 <!-- Author date --> 

thanks

Answer 1

You can use JAXB and StAX and do the following:

Demo

If you want comments at the beginning of the document, you can write down their goals before using JAXB to marshal objects. You need to set the Marshaller.JAXB_FRAGMENT property to true so that JAXB does not write the XML declaration.

 import javax.xml.bind.*; import javax.xml.stream.*; public class Demo { public static void main(String[] args) throws Exception { XMLOutputFactory xof = XMLOutputFactory.newFactory(); XMLStreamWriter xsw = xof.createXMLStreamWriter(System.out); xsw.writeStartDocument(); xsw.writeComment("Author date"); JAXBContext jc = JAXBContext.newInstance(Foo.class); Foo foo = new Foo(); foo.setBar("Hello World"); Marshaller marshaller = jc.createMarshaller(); marshaller.setProperty(Marshaller.JAXB_FRAGMENT, true); marshaller.marshal(foo, xsw); xsw.close(); } } 

Domain Model (Foo)

 import javax.xml.bind.annotation.XmlRootElement; @XmlRootElement public class Foo { private String bar; public String getBar() { return bar; } public void setBar(String bar) { this.bar = bar; } } 

Exit

 <?xml version="1.0" ?><!--Author date--><foo><bar>Hello World</bar></foo> 

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UPDATE

Using the StAX approach, the output will not be formatted. If you want to format, then it might be better for you:

 import java.io.OutputStreamWriter; import javax.xml.bind.JAXBContext; import javax.xml.bind.Marshaller; public class Demo { public static void main(String[] args) throws Exception { OutputStreamWriter writer = new OutputStreamWriter(System.out, "UTF-8"); writer.write("<?xml version=\"1.0\" ?>\n"); writer.write("<!--Author date-->\n"); JAXBContext jc = JAXBContext.newInstance(Foo.class); Foo foo = new Foo(); foo.setBar("Hello World"); Marshaller marshaller = jc.createMarshaller(); marshaller.setProperty(Marshaller.JAXB_FORMATTED_OUTPUT, true); marshaller.setProperty(Marshaller.JAXB_FRAGMENT, true); marshaller.marshal(foo, writer); writer.close(); } } 

Answer 2

after multiple searches just add System.out.append ("your comments"),
System.out.flush (); System.out.append ("\ n");
System.out.flush (); jaxbMarshaller.marshal (application, localNewFile); jaxbMarshaller.marshal (application, System.out);