Java Jaxb JavaBean and XML Conversion

Java Jaxb JavaBean and XML Conversion

1. Jaxb-Java Arcitecture for XML Binding

It is a standard in the industry and a technology that can generate Java classes based on XML Schema.

Jaxb2.0 is a component of Jdk1.6. The conversion between Xml and JavaBean can be completed without the support of Third-Party Jar packages.

2. Important concepts:

· JAXBContext class is the application entry for managing binding information in XML/Java.

· The Marshaller interface serializes Java objects into XML data.

· Unserialized aller interface to deserialize XML data into Java objects.

· @ XmlType: ing Java class or enumeration type to XML Schema type

· @ XmlAccessorType (XmlAccessType. FIELD) controls the serialization of fields or attributes. FIELD indicates that JAXB will automatically bind each non-static FIELD in the JAVA class, which is not instantaneous (marked by @ XmlTransient)

XML. Other values include XmlAccessType. PROPERTY and XmlAccessType. NONE.

· @ XmlAccessorOrder: controls the sorting of attributes and fields in the Jaxb binding class.

· XmlJavaTypeAdapter: uses a custom adapter (that is, extends the abstract class XmlAdapter and overwrites the marshal () and unmarshal () Methods) to serialize the Java class as Xml

· @ XmlElementWrapper: For arrays and collections (member variables containing multiple elements), generate an XML Element (called the wrapper) That wraps the array and binds it)

· @ XmlRootElement: maps Java classes or enumeration types to XML elements.

· @ XmlElement: maps an attribute in the Java class to an XML element with the same name as the attribute.

· @ XmlAttribute: maps an attribute of the Java class to an XML Attribute with the same name as the attribute.

3. Application:

The use of Jaxb is very simple. The following is a code written by myself. The Util class is used to convert between a JavaBean and Xml.

JaxbUtil class:Responsible for intercommunication with Jaxb:

Public class JaxbUtil {

Public static String convertToXml (Object obj ){

Return convertToXml (obj, UTF-8 );

}

/**
* @ Note JavaBean convert to xml
* @ Param obj
* JavaBean
* @ Param encoding
* Encoding
* @ Return xml
*/

Public static String convertToXml (Object obj, String encoding ){

String result = null;

Try {

JAXBContext context = JAXBContext. newInstance (obj. getClass ());

Extends aller extends aller = context. createMarshaller ();

Marshaller. setProperty (Marshaller. JAXB_FORMATTED_OUTPUT, true );

Extends aller. setProperty (extends aller. JAXB_ENCODING, encoding );

StringWriter writer = new StringWriter ();

Marshaller. marshal (obj, writer );

Result = writer. toString ();

} Catch (Exception ex ){

}

Return result;

}

/**
* @ Note xml to
* @ Param xml
* Xml
* @ Param c
* JavBean
* @ Return
*/

Public static T convertToJavaBean (String xml, Class C ){

T t = null;

Try {

JAXBContext context = JAXBContext. newInstance (c );

Unmarshaller unmarshaller = context. createUnmarshaller ();

T = (T) unmarshaller. unmarshal (new StringReader (xml ));

} Catch (Exception ex ){

Ex. printStackTrace ();

}

Return t;

}

}

Simple class:Simple Bean object, where the main method is to test it

@ XmlAccessorType (XmlAccessType. FIELD)

@ XmlRootElement

@ XmlType (name = boook, propOrder = {author, calendar, price, id })

Public class Simple {

@ XmlElement (required = true)

Private String author;

@ XmlElement (name = price_l, required = true)

Private float price;

 

@ XmlElement

Private Date calendar;

 

@ XmlElement

Private Integer id;

 

Public String getAuthor (){

Return author;

}

Public void setAuthor (String author ){

This. author = author;

}

Public float getPrice (){

Return price;

}

Public void setPrice (float price ){

This. price = price;

}

Public Date getCalendar (){

Return calendar;

}

Public void setCalendar (Date calendar ){

This. calendar = calendar;

}

Public Integer getId (){

Return id;

}

Public void setId (Integer id ){

This. id = id;

}

Public static void main (String [] agrs ){

Simple simple = new Simple ();

Simple. setId (100 );

Simple. setAuthor (wangbc );

Simple. setCalendar (new Date ());

Simple. setPrice (23.45f );

String str = JaxbUtil. convertToXml (simple );

System. out. println (str );

}

}

 

Collect class:The main method is used to test the Bean object.

@ XmlAccessorType (XmlAccessType. FIELD)

@ XmlRootElement (name = hard)

@ XmlType (propOrder = {name, provinceList })

Public class Collect {

@ XmlElement (name = country_name)

Private String name;

@ XmlElementWrapper (name = provinces)

@ XmlElement (name = province)

Private List ProvinceList;

 

Public String getName (){

Return name;

}

Public void setName (String name ){

This. name = name;

}

Public List GetProvinceList (){

Return provinceList;

}

Public void setProvinceList (List ProvinceList ){

This. provinceList = provinceList;

}

 

Public static void main (String [] args ){

Collect con = new Collect ();

Con. setName (China );

List List = new ArrayList ();

Province pro = new Province ();

Pro. setName (Jiangsu );

Pro. setProvCity (Nanjing );

Province pro2 = new Province ();

Pro2.setName (Zhejiang );

Pro2.setProvCity (Hangzhou );

List. add (pro );

List. add (pro2 );

Con. setProvinceList (list );

String str = JaxbUtil. convertToXml (con );

System. out. println (str );

}

}

 

@ XmlAccessorType (XmlAccessType. FIELD)

@ XmlType (propOrder = {name, provCity })

Class Province {

@ XmlElement (name = province_name)

Private String name;

@ XmlElement (name = prov_city)

Private String provCity;

 

Public String getName (){
Return name;

}

Public void setName (String name ){

This. name = name;

}

Public String getProvCity (){

Return provCity;

}

Public void setProvCity (String provCity ){

This. provCity = provCity;

}

}
As mentioned above, the conversion between JavaBean and XML is completed. Jaxb is relatively simple to use, and Jaxb does not need to introduce third-party jar for dependency. jdk is responsible for the implementation.