Logo Questions Linux Laravel Mysql Ubuntu Git Menu
 

Using JAXB generated class for an element that requires an integer with a pattern

Tags:

java

jaxb

xsd

I have an element in my XML Schema that is defined as follows:

<xs:complexType name="MyNumberCodeType">
    <xs:sequence>
        <xs:element name="Code" type="NumberCodeValueType" maxOccurs="unbounded" />
    </xs:sequence>
</xs:complexType>

Where NumberCodeValueType is:

<xs:simpleType name="NumberCodeValueType">
    <xs:restriction base="xs:int">
        <xs:pattern value="[0-7]{7}"/>
    </xs:restriction>
</xs:simpleType>

That is, my number can start with leading 0s. I can NOT modify this schema. I am using JAXB to generate my Java classes. Unfortunately, the accessor for the Code element takes a list of integers as the argument which means all leading 0s are stripped off (because, from what I can tell, there's no way to keep leading 0s in Java when using an integer type)!

Is there any way I can fix this?

Thanks for your help!

like image 441
Brian Schrameck Avatar asked Aug 24 '11 21:08

Brian Schrameck


People also ask

Which component or tool in JAXB can generate Java files from schemas?

After the Java artifacts for your application are generated, you can generate fully annotated Java classes from an XML schema file by using the JAXB schema compiler, xjc command-line tool.

What is @XmlType annotation in Java?

The @XmlType annotation can be defined for a class. The annotation element propOrder() in the @XmlType annotation allows you to specify the content order in the generated schema type. When you use the @XmlType.

What is JAXB marshalling and Unmarshalling?

JAXB definitionsMarshalling is the process of transforming Java objects into XML documents. Unmarshalling is the process of reading XML documents into Java objects. The JAXBContext class provides the client's entry point to the JAXB API.

What is @XmlRootElement in Java?

When a top level class or an enum type is annotated with the @XmlRootElement annotation, then its value is represented as XML element in an XML document. This annotation can be used with the following annotations: XmlType , XmlEnum , XmlAccessorType , XmlAccessorOrder .


1 Answers

You could do the following:

NumberFormatter

You can do this by writing your own formatter:

package forum7182533;

public class NumberFormatter {

    public static String printInt(Integer value) {
        String result = String.valueOf(value);
        for(int x=0, length = 7 - result.length(); x<length; x++) {
            result = "0" + result;
        }
        return result;
    }

    public static Integer parseInt(String value) {
        return Integer.valueOf(value);
    }

}

XMLSchema (format.xsd)

Then when you are going to generate your classes from your XML Schema:

<?xml version="1.0" encoding="UTF-8"?>
<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema">

    <xs:element name="root">
        <xs:complexType>
            <xs:sequence>
                <xs:element name="number" type="NumberCodeValueType" />
            </xs:sequence>
        </xs:complexType>
    </xs:element>

    <xs:simpleType name="NumberCodeValueType">
        <xs:restriction base="xs:int">
            <xs:pattern value="[0-7]{7}" />
        </xs:restriction>
    </xs:simpleType>

</xs:schema>

bindings.xml

You will leverage a JAXB bindings file to reference your formatter:

<jxb:bindings xmlns:xs="http://www.w3.org/2001/XMLSchema"
    xmlns:jxb="http://java.sun.com/xml/ns/jaxb" version="2.1">
    <jxb:bindings schemaLocation="format.xsd">
        <!--jxb:bindings node="//xs:simpleType[@name='NumberCodeValueType']" -->
        <jxb:bindings node="//xs:element[@name='number']">
            <jxb:property>
                <jxb:baseType>
                    <jxb:javaType name="java.lang.Integer"
                        parseMethod="forum7182533.NumberFormatter.parseInt" printMethod="forum7182533.NumberFormatter.printInt" />
                </jxb:baseType>
            </jxb:property>
        </jxb:bindings>
    </jxb:bindings>
</jxb:bindings>

XJC Call

The bindings file is referenced in the XJC call as:

xjc -d out -p forum7182533 -b bindings.xml format.xsd

Adapter1

This will cause an XmlAdapter to be created that leverages your formatter:

package forum7182533;

import javax.xml.bind.annotation.adapters.XmlAdapter;

public class Adapter1
    extends XmlAdapter<String, Integer>
{


    public Integer unmarshal(String value) {
        return (forum7182533.NumberFormatter.parseInt(value));
    }

    public String marshal(Integer value) {
        return (forum7182533.NumberFormatter.printInt(value));
    }

}

Root

The XmlAdapter will be referenced from your domain object using the @XmlJavaTypeAdapter annotation:

package forum7182533;

import javax.xml.bind.annotation.XmlAccessType;
import javax.xml.bind.annotation.XmlAccessorType;
import javax.xml.bind.annotation.XmlElement;
import javax.xml.bind.annotation.XmlRootElement;
import javax.xml.bind.annotation.XmlType;
import javax.xml.bind.annotation.adapters.XmlJavaTypeAdapter;

@XmlAccessorType(XmlAccessType.FIELD)
@XmlType(name = "", propOrder = {
    "number"
})
@XmlRootElement(name = "root")
public class Root {

    @XmlElement(required = true, type = String.class)
    @XmlJavaTypeAdapter(Adapter1 .class)
    protected Integer number;

    public Integer getNumber() {
        return number;
    }

    public void setNumber(Integer value) {
        this.number = value;
    }

}

Demo

Now if you run the following demo code:

package forum7182533;

import javax.xml.bind.JAXBContext;
import javax.xml.bind.Marshaller;

public class Demo {

    public static void main(String[] args) throws Exception {
        JAXBContext jc = JAXBContext.newInstance(Root.class);

        Root root = new Root();
        root.setNumber(4);

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

Output

You will get the desired output:

<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<root>
    <number>0000004</number>
</root>
like image 150
bdoughan Avatar answered Nov 10 '22 00:11

bdoughan