XML : XStream cannot deserialize XML due to NoClassDefFoundError

So I am trying to serialize a simple object to an XML file using the XStream library.

These result into the following exception complaining about class Person not being found. I've tried adding XStream annotations to the Person class but this had no success either.

What is the correct way to (de)serialize objects using the XStream library for

  Exception in thread "main" java.lang.NoClassDefFoundError: org/xmlpull/v1/XmlPullParserException      at com.thoughtworks.xstream.XStream.<init>(XStream.java:350)      at XMLTest.main(XMLTest.java:10)      at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)      at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)      at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)      at java.lang.reflect.Method.invoke(Method.java:497)      at com.intellij.rt.execution.application.AppMain.main(AppMain.java:140)  Caused by: java.lang.ClassNotFoundException: org.xmlpull.v1.XmlPullParserException      at java.net.URLClassLoader.findClass(URLClassLoader.java:381)      at java.lang.ClassLoader.loadClass(ClassLoader.java:424)      at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:331)      at java.lang.ClassLoader.loadClass(ClassLoader.java:357)      ... 7 more    

For completeness I am adding my code below.

  import com.thoughtworks.xstream.XStream;    public class XMLTest {        public static void main(String[] args) {            Person john = new Person("John", "Doe", 1234);            XStream xstream = new XStream();          String xml = xstream.toXML(john);            Person newJohn = (Person) xstream.fromXML(xml);            System.out.println("Hi " + newJohn.getFirstname());      }  }    

and

  public class Person {      private String firstname;      private String lastname;      private int age;        public Person(String firstname, String lastname, int age) {          this.firstname = firstname;          this.lastname = lastname;          this.age = age;      }        public String getFirstname() {          return firstname;      }        public void setFirstname(String firstname) {          this.firstname = firstname;      }        public String getLastname() {          return lastname;      }        public void setLastname(String lastname) {          this.lastname = lastname;      }        public int getAge() {          return age;      }        public void setAge(int age) {          this.age = age;      }  }