Remove xsi:type, xmlns:xs, and xmlns:xsi from JAXB Generics

Question

When using JAXB, I\'d like to remove the excess namespaces/types from my XML elements when using Generics. How can I do this or what am I doing wrong? I\'d like to use Gen

Answer 1

I was able to use @XmlAnyElement(lax=true) on the property that was causing me problems due to the generic parameter, then had to add an @XmlRootElement on the actual class that was being marshalled, and the declaration went away! Fantastic!

Answer 2

Test Generic

Your JAXB (JSR-222) implementation is going to create mappings per class (i.e. TestGeneric, not type (i.e. TestGeneric<Integer>). As such it is going to treat the value field as type Object. This will result in the xsi:type attributes as your JAXB implementation is adding enough information to be able to unmarshal the same types.

@XmlAccessorType(XmlAccessType.NONE)
static class TestGeneric<T> {
    @XmlAttribute public boolean isRequired;
    @XmlElement public T value;

    public TestGeneric() {
    }

    public TestGeneric(boolean isRequired) {
        this.isRequired = isRequired;
    }
}

---

Demo

Below is an approach you could use. I have introduced subclasses of TestGeneric to represent the different possible types.

package forum11192623;

import java.io.PrintWriter;
import java.io.StringWriter;

import javax.xml.bind.*;
import javax.xml.bind.annotation.*;

public class Demo {

    public static void main(String[] args) {
        try {
            TestRoot root = new TestRoot();
            root.name.value = "bobby";
            root.age.value = 102;
            root.color.value = "blue";

            JAXBContext context = JAXBContext.newInstance(root.getClass());
            Marshaller marsh = context.createMarshaller();
            marsh.setProperty(Marshaller.JAXB_ENCODING,"UTF-8");
            marsh.setProperty(Marshaller.JAXB_FORMATTED_OUTPUT,Boolean.TRUE);

            StringWriter sw = new StringWriter();
            PrintWriter pw = new PrintWriter(sw);
            marsh.marshal(root,pw);
            System.out.println(sw.toString());
        }
        catch(Throwable t) {
            t.printStackTrace();
        }
    }

    @XmlRootElement
    static class TestRoot {
        @XmlElement public TestString name = new TestString(true);
        @XmlElement public TestInteger age = new TestInteger(true);
        @XmlElement public TestString color = new TestString(true);
    }

    @XmlAccessorType(XmlAccessType.NONE)
    @XmlTransient
    @XmlSeeAlso({TestInteger.class, TestString.class})
    static class TestGeneric<T> {
        @XmlAttribute 
        public boolean isRequired;
        public T value;

        public TestGeneric() {
        }

        public TestGeneric(boolean isRequired) {
            this.isRequired = isRequired;
        }
    }

    static class TestInteger extends TestGeneric<Integer> {
        public TestInteger() {
        }
        public TestInteger(boolean b) {
            super(b);
        }
        @XmlElement
        public Integer getValue() {
            return value;
        }
        public void setValue(Integer value) {
            this.value = value;
        }
    }

    static class TestString extends TestGeneric<String> {
        public TestString() {
        }
        public TestString(boolean b) {
            super(b);
        }
        @XmlElement
        public String getValue() {
            return value;
        }
        public void setValue(String value) {
            this.value = value;
        }
    }

}

Answer 3

i get the same problem, and resolved it by the advice from Programmatically determine if a JAXB annotation will result in a xsi:type annotation?

just using @XmlAnyElement(lax=true) instead of using @XmlElement on the generic class object (value for this sample).