Understanding JAXB: Java Architecture for XML Binding

JAXB(Java Architecture for XML Binding) Internet Computing Laboratory @ KUT (http://icl.kut.ac.kr) Youn-Hee Han

What is JAXB? • JAXB (Java Architecture for XML Binding) • SAX와 DOM을 대체하는 기술 • Java 프로그래머로 하여금 Java Class와 XML 을 매핑할 수 있도록 함 • 중요 기능 • Convert XML Schemainto Class Representation • Marshal Java objects into XML • Unmarshal XML back into Java objects.

Convert XML Schema into Class Representation • XML Schema 준비 • XML 바인딩 컴파일러 – xjc 컴파일러 • xjc –p kut.ime.jaxb –d . birthdate.xsd D:/JAXBExample/birthdate.xsd <?xml version="1.0" encoding="UTF-8"?> <xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema"> <xs:element name="birthdate"> <xs:complexType> <xs:sequence> <xs:element name="month" type="xs:string" /> <xs:element name="day" type="xs:int" /> <xs:element name="year" type="xs:int" /> </xs:sequence> </xs:complexType> </xs:element> </xs:schema>

Convert XML Schema into Class Representation • 생성된 Birthdate.java 파일의 주 내용 D:/JAXBExample/kut/ime/jaxb/birthdate.java package kut.ime.jaxb; public class Birthdate { protected String month; protected int day; protected int year; String getMonth() { … } void setMonth(String value) { … } int getDay() { … } void setDay(int value) { … } int getYear() { … } void setYear(int value) { … } }

Unmarshalling (XML  Java Object) • 기존 XML Schema의 인스턴스 xml 문서 준비 D:/JAXBExample/birthdateInstance.xml <?xml version="1.0" encoding="UTF-8" standalone="yes"?> <birthdate> <month>January</month> <day>1</day> <year>1900</year> </birthdate>

Unmarshalling (XML  Java Object) • Unmarshalling 예제 D:/JAXBExample/kut/ime/jaxb/ JAXBUnmarshal.java package kut.ime.jaxb; import javax.xml.bind.*; import java.io.File; public class JAXBUnmarshal { public static void main(String[] args) { try { JAXBContext jc = JAXBContext.newInstance("kut.ime.jaxb"); Unmarshaller unmarshaller = jc.createUnmarshaller(); Birthdate instance = (Birthdate)unmarshaller.unmarshal(new File("birthdateInstance.xml")); System.out.println("Month is: " + instance.getMonth()); System.out.println("Day is: " + instance.getDay()); System.out.println("Year is: " + instance.getYear()); } catch (Exception e) { System.err.println(e); } } }

Unmarshalling (XML  Java Object) • Unmarshalling 예제 컴파일 • D:/JAXBExample 폴더에서 다음 명령 실행 • javac –d . kut/ime/jaxb/JAXBUnmarshal.java • javac –d . kut/ime/jaxb/ObjectFactory.java • 수행결과 모습 • 실행 • D:/JAXBExample 폴더에서 다음 명령 실행 • java kut.ime.jaxb.JAXBUnmarshal • 수행결과 모습

Marshalling (Java Object  XML) • Marshalling 예제 D:/JAXBExample/kut/ime/jaxb/JAXBMarshal.java package kut.ime.jaxb; import javax.xml.bind.*; import java.io.File; import java.io.FileOutputStream; public class JAXBMarshal { public static void main(String[] args) { try { ObjectFactory objFactory = new ObjectFactory(); Birthdate birthdate = objFactory.createBirthdate(); birthdate.setMonth("January"); birthdate.setDay(1); birthdate.setYear(1900); JAXBContext jaxbContext = JAXBContext.newInstance("kut.ime.jaxb"); Marshaller marshaller = jaxbContext.createMarshaller(); marshaller.setProperty(Marshaller.JAXB_FORMATTED_OUTPUT, new Boolean(true)); marshaller.marshal(birthdate, new FileOutputStream("birthdateInstance2.xml")); } catch (Exception e) { System.err.println(e); } } }

Marshalling (Java Object  XML) • Marshalling 예제 컴파일 • D:/JAXBExample 폴더에서 다음 명령 실행 • javac –d . kut/ime/jaxb/JAXBMarshal.java • 수행결과 모습 • 실행 • D:/JAXBExample 폴더에서 다음 명령 실행 • java kut.ime.jaxb.JAXBMarshal • 수행결과 • 같은폴더에 birthdateInstance2.xml 가 생성되어 있음을 확인 • 파일 내용 확인

Understanding JAXB: Java Architecture for XML Binding