How To Converts Coffee Object To Xml - Jaxb Example

JAXB, stands for Java API for XML Binding or sometimes Java Architecture for XML Binding is a decade onetime technology scientific discipline to withdraw convert a Java object into XML document (marshaling) as well as dorsum to XML file into Java object(unmarshalling). It uses combination of annotations as well as getters as well as setters to marshal Java object into XML. JAXB genuinely defines the behaviour of a touchstone gear upward of tools as well as interfaces that automatically generate Java shape files from XML schema, recall JAXB is genuinely a framework as well as architecture, non an implementation. The parcel java.xml.bind provides a runtime binding framework for clients to marshal, unmarshal as well as validate XML file inward Java. BTW, JAXB is non the alone option to parse XML inward Java, yous tin halt ever role SAX or DOM parser or JAXP API to convert XML to Java object as well as vice-versa. If yous desire to acquire to a greater extent than almost XML processing inward Java, I propose to expect at chapter ii of Core Java Volume 2 By Cay S. Horstmann. This majority covers non alone DOM as well as SAX only also StAX parser as well as locating information amongst XPath.

How to role JAXB inward Java - An Example

Let's run into how yous tin halt role JAXB to exercise XML document from Java classes This is how JAXB works, let's say yous accept a Item object that needs to live converted to XML document, all yous ask to exercise is exercise a shape Item amongst getters as well as annotate them appropriately equally shown below :

@XmlRootElement public class Item{     private int id;     private String name;     private long price;          public Item(){         // no declaration constructor required past times JAXB     }     public Item(int id, String name, long price) {         super();         this.id = id;         this.name = name;         this.price = price;     }      @XmlElement     public int getId() {         return id;     }      @XmlElement     public String getName() {         return name;     }      @XmlElement     public long getPrice() {         return price;     }         }

Then yous exercise a marshaller from JAXBContext shape as well as inquire it to convert an illustration of shape Item into XML, equally shown below :

Item dvd = new Item(101, "Lord of the Rings", 10); JAXBContext context = JAXBContext.newInstance(Item.class); Marshaller marshaller = context.createMarshaller(); marshaller.marshal(dvd, System.out);    

This volition impress next XML String into your console :

You tin halt run into how tardily it is to convert a Java object to XML using JAXB. You don't ask to worry almost mapping types, opening tag, closing tag or doing anything related to XML past times hand.

Here is the consummate Java programme to convert a Java object to XML file using JAXB API :

import javax.xml.bind.JAXBContext; import javax.xml.bind.JAXBException; import javax.xml.bind.Marshaller; import javax.xml.bind.annotation.XmlElement; import javax.xml.bind.annotation.XmlRootElement;  /** * Java programme to convert Java object to XML Document using * JAXB API. Converting a Java object to XML is also knonwn * equally marshalling as well as contrary procedure is called unmarshalling. * * @author Javin Paul */ public class JAXBDemo{      public static void main(String args[]) throws JAXBException {          lastly Item dvd = new Item(101, "Lord of the Rings", 10);         lastly JAXBContext context = JAXBContext.newInstance(Item.class);         lastly Marshaller marshaller = context.createMarshaller();         marshaller.marshal(dvd, System.out);            }      }  @XmlRootElement class Item{     private int id;     private String name;     private long price;          public Item(){         // no declaration constructor required past times JAXB     }     public Item(int id, String name, long price) {         super();         this.id = id;         this.name = name;         this.price = price;     }      @XmlElement     public int getId() {         return id;     }      @XmlElement     public String getName() {         return name;     }      @XmlElement     public long getPrice() {         return price;     }           }

Things to continue inward heed :

1) Your Java shape must accept a no-argument constructor, otherwise JAXB volition non able to marshal it. You volition acquire next Exception :

Exception in thread "main" com.sun.xml.internal.bind.v2.runtime.IllegalAnnotationsException: 1 counts of IllegalAnnotationExceptions Item does not accept a no-arg default constructor.     at com.sun.xml.internal.bind.v2.runtime.IllegalAnnotationsException$Builder.check(Unknown Source)     at com.sun.xml.internal.bind.v2.runtime.JAXBContextImpl.getTypeInfoSet(Unknown Source)     at com.sun.xml.internal.bind.v2.runtime.JAXBContextImpl.<init>(Unknown Source)     at com.sun.xml.internal.bind.v2.runtime.JAXBContextImpl.<init>(Unknown Source)     at com.sun.xml.internal.bind.v2.runtime.JAXBContextImpl$JAXBContextBuilder.build(Unknown Source)     at com.sun.xml.internal.bind.v2.ContextFactory.createContext(Unknown Source)     at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)     at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)     at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)     at java.lang.reflect.Method.invoke(Unknown Source)     at javax.xml.bind.ContextFinder.newInstance(Unknown Source)     at javax.xml.bind.ContextFinder.newInstance(Unknown Source)     at javax.xml.bind.ContextFinder.find(Unknown Source)     at javax.xml.bind.JAXBContext.newInstance(Unknown Source)     at javax.xml.bind.JAXBContext.newInstance(Unknown Source)

2) Always recall to annotate your Java shape amongst @XmlRootElement annotation, this would live your principal tag inward XML as well as each belongings using @XmlElement, they volition appear equally tyke chemical component subdivision of the principal tag.

That's all almost how to convert Java Object to XML. In adjacent tutorial yous volition acquire how to exercise unmarshalling i.e. converting an XML dorsum to Java object. Even though yous powerfulness know almost diverse XML parsers e.g. DOM, SAX as well as StAX, its proficient to know JAXP as well as JAXB equally well. As Java as well as XML goes paw as well as hand, they add together roughly other tool into Java developer's arsenal. If yous are looking for roughly books to acquire XML processing inward Java, yous tin halt ever refer meat Java majority ii for basic knowledge. It volition give yous prissy overview of dissimilar parser, XML binding as well as XPath, only if yous desire to acquire inward to a greater extent than inward depth as well as then yous tin halt refer Java as well as XML past times Brett McLaughlin. Its roughly other proficient majority to acquire almost XML processing inward Java.

Further Learning
Java In-Depth: Become a Complete Java Engineer!
Master Java Web Services as well as REST API amongst Spring Boot
Java Web Fundamentals

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