For example i have an xsd, and i want to generate an XML based on it using java. This is my xsd example, and i save it as “my.xsd”

<xsd:schema xmlns:xsd="http://www.w3.org/2001/XMLSchema"
           xmlns:tns="http://tempuri.org/PurchaseOrderSchema.xsd"
           targetNamespace="http://tempuri.org/PurchaseOrderSchema.xsd"
           elementFormDefault="qualified">
 <xsd:element name="PurchaseOrder" type="tns:PurchaseOrderType"/>
 <xsd:complexType name="PurchaseOrderType">
  <xsd:sequence>
   <xsd:element name="ShipTo" type="tns:USAddress" maxOccurs="2"/>
   <xsd:element name="BillTo" type="tns:USAddress"/>
  </xsd:sequence>
  <xsd:attribute name="OrderDate" type="xsd:date"/>
 </xsd:complexType>

 <xsd:complexType name="USAddress">
  <xsd:sequence>
   <xsd:element name="name"   type="xsd:string"/>
   <xsd:element name="street" type="xsd:string"/>
   <xsd:element name="city"   type="xsd:string"/>
   <xsd:element name="state"  type="xsd:string"/>
   <xsd:element name="zip"    type="xsd:integer"/>
  </xsd:sequence>
  <xsd:attribute name="country" type="xsd:NMTOKEN" fixed="US"/>
 </xsd:complexType>
</xsd:schema>

Next step is generate java bean using xjc using below command

xjc -p com.edw.bean my.xsd

And it will gives below output,

parsing a schema...
compiling a schema...
com\edw\bean\ObjectFactory.java
com\edw\bean\PurchaseOrderType.java
com\edw\bean\USAddress.java
com\edw\bean\package-info.java

Import those generated java files, and print a simple xml on console based on it.

package com.edw;

import com.edw.bean.ObjectFactory;
import com.edw.bean.PurchaseOrderType;
import com.edw.bean.USAddress;

import javax.xml.bind.JAXBContext;
import javax.xml.bind.JAXBElement;
import javax.xml.bind.Marshaller;
import javax.xml.datatype.DatatypeFactory;
import java.math.BigInteger;
import java.util.Date;

public class Main {
    public static void main(String[] args) throws Exception {
        new Main().doSomething();
    }

    private void doSomething() throws Exception {
        PurchaseOrderType purchaseOrderType = new PurchaseOrderType();
        USAddress address = new USAddress();
        address.setCity("aaa");
        address.setCountry("US");
        address.setName("cccc");
        address.setState("dddd");
        address.setStreet("eee");
        address.setZip(BigInteger.ONE);

        purchaseOrderType.setBillTo(address);
        purchaseOrderType.getShipTo().add(address);
        purchaseOrderType.setOrderDate(DatatypeFactory.newInstance().newXMLGregorianCalendar(new Date().toInstant().toString()));

        JAXBElement<PurchaseOrderType> element = new ObjectFactory().createPurchaseOrder(purchaseOrderType);
        toXml(element);
    }

    private void toXml(JAXBElement<PurchaseOrderType> element) throws Exception {
        JAXBContext ctx = JAXBContext.newInstance(PurchaseOrderType.class);
        Marshaller marshaller = ctx.createMarshaller();
        marshaller.setProperty(Marshaller.JAXB_FORMATTED_OUTPUT, Boolean.TRUE);
        marshaller.marshal(element, System.out);
    }
}

It will print below output,

<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<PurchaseOrder xmlns="http://tempuri.org/PurchaseOrderSchema.xsd" OrderDate="2019-11-11Z">
    <ShipTo country="US">
        <name>cccc</name>
        <street>eee</street>
        <city>aaa</city>
        <state>dddd</state>
        <zip>1</zip>
    </ShipTo>
    <BillTo country="US">
        <name>cccc</name>
        <street>eee</street>
        <city>aaa</city>
        <state>dddd</state>
        <zip>1</zip>
    </BillTo>
</PurchaseOrder>

Final step is we can validate our generated xml with provided xsd, and see whether generated xml is valid.