如何为XML解析创建泛型？

Question

I currently using jsoup and sometimes dom4j for parsing string of xml. Here's an example on how I do it using jsoup.

Document doc = Jsoup.parse(xml);
Elements root = doc.select("person");
for(Elements elem : elements){
Person person = new Person();
person.setFirstname(elem.select("firstName").text());
person.setLastname(elem.select("lastName").text());
person.setAddress(elem.select("address").text());
//other setters here
}

Everytime I have to parse xml I have to get all elements and set to setters of POJO. Now I want to create a Generics where I only have to do is to passed a string of xml and a class of POJO then it will set all the values of fields based on all the elements of xml. How can I do it? Any ideas?

Thanks in advance.

Answer 1

JAXB is the way to go.

Note: It is included in JAVA 1.6 and later versions

Add XML tags to your POJO (XmlRootElement is enough for simple objects, XmlElement can also be added to variables)

import javax.xml.bind.annotation.XmlRootElement;

@XmlRootElement(name = "Person")
public class Person {

    private String firstName;

    private String lastName;

    private String address;

    public final String getFirstName() {
        return firstName;
    }

    public final void setFirstName(String firstName) {
        this.firstName = firstName;
    }

    public final String getLastName() {
        return lastName;
    }

    public final void setLastName(String lastName) {
        this.lastName = lastName;
    }

    public final String getAddress() {
        return address;
    }

    public final void setAddress(String address) {
        this.address = address;
    }

    @Override
    public String toString() {
        return "FirstName: " + firstName + " LastName: " + lastName + " Address: " + address;
    }

}

Use Unmarshaller to create the POJO from the xml file.

    File file = new File("<Path to Xml file>");
    JAXBContext context = JAXBContext.newInstance(Person.class);
    Unmarshaller unmarsheller = context.createUnmarshaller();
    Person person = (Person) unmarsheller.unmarshal(file);
    System.out.println(person);

You can use Marshaller to create the XML from the POJO also.

There are more examples available here to create complex objects, add lists, arrays.

Note: It is not available in Android Platform, If you want to use it on android you can use SimpleXML with almost same implementation