How to generate JAXB classes from XSD?

I'm a total newbie with XML. I'm doing a Java EE project REST implementation and we return a lot of XML. With this we decided to use JAXB. So far, we manually coded the Models for the XML.

But there are already these complex structures we don't know how to code. We've read about generating classes from XSD. We do have an XSD.

My questions:

1.) I've read about XJC, where can I find it?

2.) Do we have to install the whole JAXB? (so what we used so far? isn't this JAXB?)


XJC is included in the bin directory in the JDK starting with Java SE 6. For an example see:

  • http://blog.bdoughan.com/2010/09/processing-atom-feeds-with-jaxb.html

The contents of the blog are the following:

Processing Atom Feeds with JAXB Atom is an XML format for representing web feeds. A standard format allows reader applications to display feeds from different sources. In this example we will process the Atom feed for this blog.

Demo

In this example we will use JAXB to convert the Atom XML feed corresponding to this blog to objects and then back to XML.

import java.io.InputStream;
import java.net.URL;
import javax.xml.bind.*;
import javax.xml.transform.stream.StreamSource;
import org.w3._2005.atom.FeedType;

public class Demo {

    public static void main(String[] args) throws Exception {
        JAXBContext jc = JAXBContext.newInstance("org.w3._2005.atom");

        Unmarshaller unmarshaller = jc.createUnmarshaller();
        URL url = new URL("http://bdoughan.blogspot.com/atom.xml");
        InputStream xml = url.openStream();
        JAXBElement<feedtype> feed = unmarshaller.unmarshal(new StreamSource(xml), FeedType.class);
        xml.close();

        Marshaller marshaller = jc.createMarshaller();
        marshaller.setProperty(Marshaller.JAXB_FORMATTED_OUTPUT, true);
        marshaller.marshal(feed, System.out);
    }

}

JAXB Model

The following model was generated by the schema to Java compiler (XJC). I have omitted the get/set methods and comments to save space.

xjc -d generated http://www.kbcafe.com/rss/atom.xsd.xml

package-info

@XmlSchema(
        namespace = "http://www.w3.org/2005/Atom",
        elementFormDefault = XmlNsForm.QUALIFIED)
@XmlAccessorType(XmlAccessType.FIELD)
package org.w3._2005.atom;

import javax.xml.bind.annotation.*;

CategoryType

package org.w3._2005.atom;

import java.util.*;
import javax.xml.bind.annotation.*;
import javax.xml.bind.annotation.adapters.*;
import javax.xml.namespace.QName;

@XmlType(name = "categoryType")
public class CategoryType {
    @XmlAttribute(required = true)
    protected String term;

    @XmlAttribute
    @XmlSchemaType(name = "anyURI")
    protected String scheme;

    @XmlAttribute
    protected String label;

    @XmlAttribute(namespace = "http://www.w3.org/XML/1998/namespace")
    @XmlSchemaType(name = "anyURI")
    protected String base;

    @XmlAttribute(namespace = "http://www.w3.org/XML/1998/namespace")
    @XmlJavaTypeAdapter(CollapsedStringAdapter.class)
    @XmlSchemaType(name = "language")
    protected String lang;

    @XmlAnyAttribute
    private Map<QName, String> otherAttributes = new HashMap<QName, String>();
}

Content Type

package org.w3._2005.atom;

import java.util.*;
import javax.xml.bind.annotation.*;
import javax.xml.bind.annotation.adapters.*;
import javax.xml.namespace.QName;

@XmlType(name = "contentType", propOrder = {"content"})
public class ContentType {
    @XmlMixed
    @XmlAnyElement(lax = true)
    protected List<Object> content;

    @XmlAttribute
    protected String type;

    @XmlAttribute
    @XmlSchemaType(name = "anyURI")
    protected String src;

    @XmlAttribute(namespace = "http://www.w3.org/XML/1998/namespace")
    @XmlSchemaType(name = "anyURI")
    protected String base;

    @XmlAttribute(namespace = "http://www.w3.org/XML/1998/namespace")
    @XmlJavaTypeAdapter(CollapsedStringAdapter.class)
    @XmlSchemaType(name = "language")
    protected String lang;

    @XmlAnyAttribute
    private Map<QName, String> otherAttributes = new HashMap<QName, String>();
}

DateTimeType

package org.w3._2005.atom;

import java.util.*;
import javax.xml.bind.annotation.*;
import javax.xml.bind.annotation.adapters.*;
import javax.xml.datatype.XMLGregorianCalendar;
import javax.xml.namespace.QName;

@XmlType(name = "dateTimeType", propOrder = {"value"})
public class DateTimeType {
    @XmlValue
    @XmlSchemaType(name = "dateTime")
    protected XMLGregorianCalendar value;

    @XmlAttribute(namespace = "http://www.w3.org/XML/1998/namespace")
    @XmlSchemaType(name = "anyURI")
    protected String base;

    @XmlAttribute(namespace = "http://www.w3.org/XML/1998/namespace")
    @XmlJavaTypeAdapter(CollapsedStringAdapter.class)
    @XmlSchemaType(name = "language")
    protected String lang;

    @XmlAnyAttribute
    private Map<QName, String> otherAttributes = new HashMap<QName, String>();
}

EntryType

package org.w3._2005.atom;

import java.util.*;
import javax.xml.bind.JAXBElement;
import javax.xml.bind.annotation.*;
import javax.xml.bind.annotation.adapters.*;
import javax.xml.namespace.QName;

@XmlType(name = "entryType", propOrder = {"authorOrCategoryOrContent"})
public class EntryType {
    @XmlElementRefs({
        @XmlElementRef(name = "id", namespace = "http://www.w3.org/2005/Atom", type = JAXBElement.class),
        @XmlElementRef(name = "rights", namespace = "http://www.w3.org/2005/Atom", type = JAXBElement.class),
        @XmlElementRef(name = "summary", namespace = "http://www.w3.org/2005/Atom", type = JAXBElement.class),
        @XmlElementRef(name = "title", namespace = "http://www.w3.org/2005/Atom", type = JAXBElement.class),
        @XmlElementRef(name = "author", namespace = "http://www.w3.org/2005/Atom", type = JAXBElement.class),
        @XmlElementRef(name = "source", namespace = "http://www.w3.org/2005/Atom", type = JAXBElement.class),
        @XmlElementRef(name = "updated", namespace = "http://www.w3.org/2005/Atom", type = JAXBElement.class),
        @XmlElementRef(name = "category", namespace = "http://www.w3.org/2005/Atom", type = JAXBElement.class),
        @XmlElementRef(name = "content", namespace = "http://www.w3.org/2005/Atom", type = JAXBElement.class),
        @XmlElementRef(name = "published", namespace = "http://www.w3.org/2005/Atom", type = JAXBElement.class),
        @XmlElementRef(name = "contributor", namespace = "http://www.w3.org/2005/Atom", type = JAXBElement.class),
        @XmlElementRef(name = "link", namespace = "http://www.w3.org/2005/Atom", type = JAXBElement.class)
    })
    @XmlAnyElement(lax = true)
    protected List<Object> authorOrCategoryOrContent;

    @XmlAttribute(namespace = "http://www.w3.org/XML/1998/namespace")
    @XmlSchemaType(name = "anyURI")
    protected String base;

    @XmlAttribute(namespace = "http://www.w3.org/XML/1998/namespace")
    @XmlJavaTypeAdapter(CollapsedStringAdapter.class)
    @XmlSchemaType(name = "language")
    protected String lang;

    @XmlAnyAttribute
    private Map<QName, String> otherAttributes = new HashMap<QName, String>();
}

FeedType

package org.w3._2005.atom;

import java.util.*;
import javax.xml.bind.JAXBElement;
import javax.xml.bind.annotation.*;
import javax.xml.bind.annotation.adapters.*;
import javax.xml.namespace.QName;

@XmlType(name = "feedType", propOrder = {"authorOrCategoryOrContributor"})
public class FeedType {
    @XmlElementRefs({
        @XmlElementRef(name = "link", namespace = "http://www.w3.org/2005/Atom", type = JAXBElement.class),
        @XmlElementRef(name = "updated", namespace = "http://www.w3.org/2005/Atom", type = JAXBElement.class),
        @XmlElementRef(name = "category", namespace = "http://www.w3.org/2005/Atom", type = JAXBElement.class),
        @XmlElementRef(name = "rights", namespace = "http://www.w3.org/2005/Atom", type = JAXBElement.class),
        @XmlElementRef(name = "contributor", namespace = "http://www.w3.org/2005/Atom", type = JAXBElement.class),
        @XmlElementRef(name = "title", namespace = "http://www.w3.org/2005/Atom", type = JAXBElement.class),
        @XmlElementRef(name = "id", namespace = "http://www.w3.org/2005/Atom", type = JAXBElement.class),
        @XmlElementRef(name = "generator", namespace = "http://www.w3.org/2005/Atom", type = JAXBElement.class),
        @XmlElementRef(name = "icon", namespace = "http://www.w3.org/2005/Atom", type = JAXBElement.class),
        @XmlElementRef(name = "subtitle", namespace = "http://www.w3.org/2005/Atom", type = JAXBElement.class),
        @XmlElementRef(name = "author", namespace = "http://www.w3.org/2005/Atom", type = JAXBElement.class),
        @XmlElementRef(name = "entry", namespace = "http://www.w3.org/2005/Atom", type = JAXBElement.class),
        @XmlElementRef(name = "logo", namespace = "http://www.w3.org/2005/Atom", type = JAXBElement.class)
    })
    @XmlAnyElement(lax = true)
    protected List<Object> authorOrCategoryOrContributor;

    @XmlAttribute(namespace = "http://www.w3.org/XML/1998/namespace")
    @XmlSchemaType(name = "anyURI")
    protected String base;

    @XmlAttribute(namespace = "http://www.w3.org/XML/1998/namespace")
    @XmlJavaTypeAdapter(CollapsedStringAdapter.class)
    @XmlSchemaType(name = "language")
    protected String lang;

    @XmlAnyAttribute
    private Map<QName, String> otherAttributes = new HashMap<QName, String>();
}

GeneratorType

package org.w3._2005.atom;

import java.util.*;
import javax.xml.bind.annotation.*;
import javax.xml.bind.annotation.adapters.*;
import javax.xml.namespace.QName;

@XmlType(name = "generatorType", propOrder = {"value"})
public class GeneratorType {
    @XmlValue
    protected String value;

    @XmlAttribute
    @XmlSchemaType(name = "anyURI")
    protected String uri;

    @XmlAttribute
    protected String version;

    @XmlAttribute(namespace = "http://www.w3.org/XML/1998/namespace")
    @XmlSchemaType(name = "anyURI")
    protected String base;

    @XmlAttribute(namespace = "http://www.w3.org/XML/1998/namespace")
    @XmlJavaTypeAdapter(CollapsedStringAdapter.class)
    @XmlSchemaType(name = "language")
    protected String lang;

    @XmlAnyAttribute
    private Map<QName, String> otherAttributes = new HashMap<QName, String>();
}

IconType

package org.w3._2005.atom;

import java.util.*;
import javax.xml.bind.annotation.*;
import javax.xml.bind.annotation.adapters.*;
import javax.xml.namespace.QName;

@XmlType(name = "iconType", propOrder = {"value"})
public class IconType {
    @XmlValue
    @XmlSchemaType(name = "anyURI")
    protected String value;

    @XmlAttribute(namespace = "http://www.w3.org/XML/1998/namespace")
    @XmlSchemaType(name = "anyURI")
    protected String base;

    @XmlAttribute(namespace = "http://www.w3.org/XML/1998/namespace")
    @XmlJavaTypeAdapter(CollapsedStringAdapter.class)
    @XmlSchemaType(name = "language")
    protected String lang;

    @XmlAnyAttribute
    private Map<QName, String> otherAttributes = new HashMap<QName, String>();
}

IdType

package org.w3._2005.atom;

import java.util.*;
import javax.xml.bind.annotation.*;
import javax.xml.bind.annotation.adapters.*;
import javax.xml.namespace.QName;

@XmlType(name = "idType", propOrder = {"value"})
public class IdType {
    @XmlValue
    @XmlSchemaType(name = "anyURI")
    protected String value;

    @XmlAttribute(namespace = "http://www.w3.org/XML/1998/namespace")
    @XmlSchemaType(name = "anyURI")
    protected String base;

    @XmlAttribute(namespace = "http://www.w3.org/XML/1998/namespace")
    @XmlJavaTypeAdapter(CollapsedStringAdapter.class)
    @XmlSchemaType(name = "language")
    protected String lang;

    @XmlAnyAttribute
    private Map<QName, String> otherAttributes = new HashMap<QName, String>();
}

LinkType

package org.w3._2005.atom;

import java.math.BigInteger;
import java.util.*;
import javax.xml.bind.annotation.*;
import javax.xml.bind.annotation.adapters.*;
import javax.xml.namespace.QName;

@XmlType(name = "linkType", propOrder = {"content"})
public class LinkType {
    @XmlValue
    protected String content;

    @XmlAttribute(required = true)
    @XmlSchemaType(name = "anyURI")
    protected String href;

    @XmlAttribute
    protected String rel;

    @XmlAttribute
    protected String type;

    @XmlAttribute
    @XmlJavaTypeAdapter(CollapsedStringAdapter.class)
    @XmlSchemaType(name = "NMTOKEN")
    protected String hreflang;

    @XmlAttribute
    protected String title;

    @XmlAttribute
    @XmlSchemaType(name = "positiveInteger")
    protected BigInteger length;

    @XmlAttribute(namespace = "http://www.w3.org/XML/1998/namespace")
    @XmlSchemaType(name = "anyURI")
    protected String base;

    @XmlAttribute(namespace = "http://www.w3.org/XML/1998/namespace")
    @XmlJavaTypeAdapter(CollapsedStringAdapter.class)
    @XmlSchemaType(name = "language")
    protected String lang;

    @XmlAnyAttribute
    private Map<QName, String> otherAttributes = new HashMap<QName, String>();
}

LogoType

package org.w3._2005.atom;

import java.util.*;
import javax.xml.bind.annotation.*;
import javax.xml.bind.annotation.adapters.*;
import javax.xml.namespace.QName;

@XmlType(name = "logoType", propOrder = {"value"})
public class LogoType {
    @XmlValue
    @XmlSchemaType(name = "anyURI")
    protected String value;

    @XmlAttribute(namespace = "http://www.w3.org/XML/1998/namespace")
    @XmlSchemaType(name = "anyURI")
    protected String base;

    @XmlAttribute(namespace = "http://www.w3.org/XML/1998/namespace")
    @XmlJavaTypeAdapter(CollapsedStringAdapter.class)
    @XmlSchemaType(name = "language")
    protected String lang;

    @XmlAnyAttribute
    private Map<QName, String> otherAttributes = new HashMap<QName, String>();
}

PersonType

package org.w3._2005.atom;

import java.util.*;
import javax.xml.bind.JAXBElement;
import javax.xml.bind.annotation.*;
import javax.xml.bind.annotation.adapters.*;
import javax.xml.namespace.QName;

@XmlType(name = "personType", propOrder = {"nameOrUriOrEmail"})
public class PersonType {
    @XmlElementRefs({
        @XmlElementRef(name = "email", namespace = "http://www.w3.org/2005/Atom", type = JAXBElement.class),
        @XmlElementRef(name = "name", namespace = "http://www.w3.org/2005/Atom", type = JAXBElement.class),
        @XmlElementRef(name = "uri", namespace = "http://www.w3.org/2005/Atom", type = JAXBElement.class)
    })
    @XmlAnyElement(lax = true)
    protected List<Object> nameOrUriOrEmail;

    @XmlAttribute(namespace = "http://www.w3.org/XML/1998/namespace")
    @XmlSchemaType(name = "anyURI")
    protected String base;

    @XmlAttribute(namespace = "http://www.w3.org/XML/1998/namespace")
    @XmlJavaTypeAdapter(CollapsedStringAdapter.class)
    @XmlSchemaType(name = "language")
    protected String lang;

    @XmlAnyAttribute
    private Map<QName, String> otherAttributes = new HashMap<QName, String>();
}

SourceType

package org.w3._2005.atom;

import java.util.*;
import javax.xml.bind.JAXBElement;
import javax.xml.bind.annotation.*;
import javax.xml.bind.annotation.adapters.*;
import javax.xml.namespace.QName;

@XmlType(name = "sourceType", propOrder = {"authorOrCategoryOrContributor"})
public class SourceType {
    @XmlElementRefs({
        @XmlElementRef(name = "updated", namespace = "http://www.w3.org/2005/Atom", type = JAXBElement.class),
        @XmlElementRef(name = "category", namespace = "http://www.w3.org/2005/Atom", type = JAXBElement.class),
        @XmlElementRef(name = "subtitle", namespace = "http://www.w3.org/2005/Atom", type = JAXBElement.class),
        @XmlElementRef(name = "logo", namespace = "http://www.w3.org/2005/Atom", type = JAXBElement.class),
        @XmlElementRef(name = "generator", namespace = "http://www.w3.org/2005/Atom", type = JAXBElement.class),
        @XmlElementRef(name = "icon", namespace = "http://www.w3.org/2005/Atom", type = JAXBElement.class),
        @XmlElementRef(name = "title", namespace = "http://www.w3.org/2005/Atom", type = JAXBElement.class),
        @XmlElementRef(name = "id", namespace = "http://www.w3.org/2005/Atom", type = JAXBElement.class),
        @XmlElementRef(name = "author", namespace = "http://www.w3.org/2005/Atom", type = JAXBElement.class),
        @XmlElementRef(name = "contributor", namespace = "http://www.w3.org/2005/Atom", type = JAXBElement.class),
        @XmlElementRef(name = "link", namespace = "http://www.w3.org/2005/Atom", type = JAXBElement.class),
        @XmlElementRef(name = "rights", namespace = "http://www.w3.org/2005/Atom", type = JAXBElement.class)
    })
    @XmlAnyElement(lax = true)
    protected List<Object> authorOrCategoryOrContributor;

    @XmlAttribute(namespace = "http://www.w3.org/XML/1998/namespace")
    @XmlSchemaType(name = "anyURI")
    protected String base;

    @XmlAttribute(namespace = "http://www.w3.org/XML/1998/namespace")
    @XmlJavaTypeAdapter(CollapsedStringAdapter.class)
    @XmlSchemaType(name = "language")
    protected String lang;

    @XmlAnyAttribute
    private Map<QName, String> otherAttributes = new HashMap<QName, String>();
}

TextType

package org.w3._2005.atom;

import java.util.*;
import javax.xml.bind.annotation.*;
import javax.xml.bind.annotation.adapters.*;
import javax.xml.namespace.QName;

@XmlType(name = "textType", propOrder = {"content"})
public class TextType {
    @XmlMixed
    @XmlAnyElement(lax = true)
    protected List<Object> content;

    @XmlAttribute
    @XmlJavaTypeAdapter(CollapsedStringAdapter.class)
    protected String type;

    @XmlAttribute(namespace = "http://www.w3.org/XML/1998/namespace")
    @XmlSchemaType(name = "anyURI")
    protected String base;

    @XmlAttribute(namespace = "http://www.w3.org/XML/1998/namespace")
    @XmlJavaTypeAdapter(CollapsedStringAdapter.class)
    @XmlSchemaType(name = "language")
    protected String lang;

    @XmlAnyAttribute
    private Map<QName, String> otherAttributes = new HashMap<QName, String>();
}

UriType

package org.w3._2005.atom;

import java.util.*;
import javax.xml.bind.annotation.*;
import javax.xml.bind.annotation.adapters.*;
import javax.xml.namespace.QName;

@XmlType(name = "uriType", propOrder = {"value"})
public class UriType {
    @XmlValue
    @XmlSchemaType(name = "anyURI")
    protected String value;

    @XmlAttribute(namespace = "http://www.w3.org/XML/1998/namespace")
    @XmlSchemaType(name = "anyURI")
    protected String base;

    @XmlAttribute(namespace = "http://www.w3.org/XML/1998/namespace")
    @XmlJavaTypeAdapter(CollapsedStringAdapter.class)
    @XmlSchemaType(name = "language")
    protected String lang;

    @XmlAnyAttribute
    private Map<QName, String> otherAttributes = new HashMap<QName, String>();
}

For Eclipse STS (3.5 at least) you don't need to install anything. Right click on schema.xsd -> Generate -> JAXB Classes. You'll have to specify the package & location in the next step and that's all, your classes should be generated. I guess all the above mentioned solutions work, but this seems by far the easiest (for STS users).

[UPDATE] Eclipse STS version 3.6 (based on Kepler) comes with the same functionality.

blah


1) You can use standard java utility xjc - ([your java home dir]\bin\xjc.exe). But you need to create .bat (or .sh) script for using it.

e.g. generate.bat:

[your java home dir]\bin\xjc.exe %1 %2 %3

e.g. test-scheme.xsd:

<?xml version="1.0"?>
<xs:schema version="1.0"
           xmlns:xs="http://www.w3.org/2001/XMLSchema"
           elementFormDefault="qualified" 
           targetNamespace="http://myprojects.net/xsd/TestScheme"
           xmlns="http://myprojects.net/xsd/TestScheme">
    <xs:element name="employee" type="PersonInfoType"/>

    <xs:complexType name="PersonInfoType">
        <xs:sequence>
            <xs:element name="firstname" type="xs:string"/>
            <xs:element name="lastname" type="xs:string"/>
        </xs:sequence>
    </xs:complexType>
</xs:schema>

Run .bat file with parameters: generate.bat test-scheme.xsd -d [your src dir]

For more info use this documentation - http://docs.oracle.com/javaee/5/tutorial/doc/bnazg.html

and this - http://docs.oracle.com/javase/6/docs/technotes/tools/share/xjc.html

2) JAXB (xjc utility) is installed together with JDK6 by default.


  • If you're using Eclipse, you can also try out JAXB Eclipse Plug-In

  • You can find more information about XJC Binding Compiler that comes with the jdk installation over here: xjc: Java™ Architecture for XML Binding -Binding Compiler

I hope this helps!


cxf does great support for this kind of stuff e.g

<plugin>
    <groupId>org.apache.cxf</groupId>
    <artifactId>cxf-xjc-plugin</artifactId>
    <version>2.3.0</version>
    <configuration>
      <extensions>
        <extension>org.apache.cxf.xjcplugins:cxf-xjc-dv:2.3.0</extension>
      </extensions>
    </configuration>
    <executions>
      <execution>
        <id>generate-sources-trans</id>
        <phase>generate-sources</phase>
        <goals>
          <goal>xsdtojava</goal>
        </goals>
        <configuration>
          <sourceRoot>${basedir}/src/main/java</sourceRoot>
          <xsdOptions>
            <xsdOption>
              <xsd>src/main/resources/xxx.xsd</xsd>
            </xsdOption>
          </xsdOptions>
        </configuration>
      </execution>
    </executions>
  </plugin>