Pojo to xsd generation

Question

Is there a library which could generate a xsd schema from a java class? Google yields lots of results the opposite ( java classes from xsd ).

Answer 1

Thanks for giving your method. Just wanted to add complete example.

import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.OutputStream;
import java.util.ArrayList;
import java.util.List;

import javax.xml.bind.JAXBContext;
import javax.xml.bind.JAXBException;
import javax.xml.bind.SchemaOutputResolver;
import javax.xml.transform.OutputKeys;
import javax.xml.transform.Result;
import javax.xml.transform.Transformer;
import javax.xml.transform.TransformerException;
import javax.xml.transform.TransformerFactory;
import javax.xml.transform.dom.DOMResult;
import javax.xml.transform.dom.DOMSource;
import javax.xml.transform.stream.StreamResult;

import test.Test;

public class Main {
    public static void main(String[] args) throws JAXBException,
            FileNotFoundException {

         JAXBContext context = JAXBContext.newInstance("test");
         try {
            new Main().pojoToXSD(context, new Test(), System.out);
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        } catch (TransformerException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }

    }
    public void pojoToXSD(JAXBContext context, Object pojo, OutputStream out) 
            throws IOException, TransformerException 
        {
            final List<DOMResult> results = new ArrayList<DOMResult>();

            context.generateSchema(new SchemaOutputResolver() {

                @Override
                public Result createOutput(String ns, String file)
                        throws IOException {
                    DOMResult result = new DOMResult();
                    result.setSystemId(file);
                    results.add(result);
                    return result;
                }
            });

            DOMResult domResult = results.get(0);
            com.sun.org.apache.xerces.internal.dom.DocumentImpl doc = com.sun.org.apache.xerces.internal.dom.DocumentImpl) domResult.getNode();

            // Use a Transformer for output
            TransformerFactory tFactory = TransformerFactory.newInstance();
            Transformer transformer = tFactory.newTransformer();

            DOMSource source = new DOMSource(doc);
            StreamResult result = new StreamResult(out);
            transformer.setOutputProperty(OutputKeys.INDENT, "yes");
            transformer.transform(source, result);
        }
}

//---------- below will go in test package

package test;

import javax.xml.bind.annotation.XmlRegistry;
import javax.xml.namespace.QName;




@XmlRegistry
public class ObjectFactory {

    private final static QName _Test_QNAME = new Name("urn:vertexinc:enterprise:calendar:1:0", "Test");


    public ObjectFactory() {
    }
    public Test createTest() {
        return new Test();
    }

   }


    package test;

    public class Test {
    String name;
    String cls;

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public String getCls() {
        return cls;
    }

    public void setCls(String cls) {
        this.cls = cls;
    }

    }

Answer 2

Here is how I would do it:

public static void pojoToXSD(Class<?> pojo, OutputStream out) throws IOException, TransformerException, JAXBException {
    JAXBContext context = JAXBContext.newInstance(pojo);
    final List<DOMResult> results = new ArrayList<>();

    context.generateSchema(new SchemaOutputResolver() {

        @Override
        public Result createOutput(String ns, String file)
                throws IOException {
            DOMResult result = new DOMResult();
            result.setSystemId(file);
            results.add(result);
            return result;
        }
    });

    DOMResult domResult = results.get(0);

    // Use a Transformer for output
    TransformerFactory tFactory = TransformerFactory.newInstance();
    Transformer transformer = tFactory.newTransformer();

    DOMSource source = new DOMSource(domResult.getNode());
    StreamResult result = new StreamResult(out);
    transformer.setOutputProperty(OutputKeys.INDENT, "yes");
    transformer.transform(source, result);
}

How to use the method above

try {
        ByteArrayOutputStream stream = new ByteArrayOutputStream();

        pojoToXSD(NESingleResponse.class, stream);

        String finalString = new String(stream.toByteArray());
        System.out.println(finalString);
    } catch (JAXBException ex) {
        Logger.getLogger(NewClass.class.getName()).log(Level.SEVERE, null, ex);
    }

Answer 3

JAXB 2.0 allows you to create a XML schema from an annotated Java class.

You'll find some examples at the AMIS blog and at the JavaPassion site.

Answer 4

JiBX does this

The schema generator tool first reads one or more JiBX binding definitions and then uses reflection to interpret the structure of the Java classes referenced in the bindings. By combining the binding definitions with the actual class information the schema generator is able to construct one or more XML schemas to represent the documents handled by the bindings.