JAXB difference between XsdSchema and XsdSchemaCollection while creating the DefaultWsdl11Definition bean

Question

I explore the JAXB and the JAXB2 Maven plugin. I am confused of the bean instantiation.

I have two schemas in src/main/resources with the same namespace www.mycompany.com. schemaA.xsd and schemaB.xsd have the same header:

<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema"
    xmlns:tns="http://www.mycompany.com"
    targetNamespace="http://www.mycompany.com"
    elementFormDefault="qualified">

My WebServiceConfiguration extending WsConfigurerAdapter defines aside the ServletRegistrationBean also the following XsdSchema(Collection) beans:

// Just a bean with one schema
@Bean
public XsdSchema schema() {
    return new SimpleXsdSchema(new ClassPathResource("xsd/schemaA.xsd"));
}

// A bean with both schemas
@Bean
public XsdSchemaCollection schemaCollection() {
    return new XsdSchemaCollection() {

        @Override
        public XsdSchema[] getXsdSchemas() {
            return new XsdSchema[] {
                    new SimpleXsdSchema(new ClassPathResource("xsd/schemaA.xsd")),
                    new SimpleXsdSchema(new ClassPathResource("xsd/schemaB.xsd"))
            };
        }

        @Override
        public XmlValidator createValidator() {
            throw new UnsupportedOperationException();
        }
    };
}

And the WSDL bean:

@Bean(name = "soapWsdl")
public DefaultWsdl11Definition defaultWsdl11Definition(XsdSchema schema, XsdSchemaCollection schemaCollection) {
    DefaultWsdl11Definition wsdl11Definition = new DefaultWsdl11Definition();
    wsdl11Definition.setPortTypeName("SoapPort");
    wsdl11Definition.setLocationUri("/service/soap");
    wsdl11Definition.setTargetNamespace("https://www.mycompany.com");

    // At this point I use just one of the folliwing
    wsdl11Definition.setSchema(schema);
    wsdl11Definition.setSchemaCollection(schemaCollection);

    return wsdl11Definition;
}

Using one of these in the bean above:

wsdl11Definition.setSchema(schema);

If I use only XsdSchema defining one schema (regardless whether schemaA or schemaB), everything works, the SOAP Web service is running and WSDL is generated
wsdl11Definition.setSchemaCollection(schemaCollection);

Now the NPE is thrown although the InliningXsdSchemaTypesProvider sets the one schema as the collection with one schema. The error thrown is:

2018-10-05 21:29:28.636 WARN 164968 --- [ main] ConfigServletWebServerApplicationContext : Exception encountered during context initialization - cancelling refresh attempt: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'soapWsdl' defined in class path resource [cz/vse/soap/WebServiceConfig.class]: Bean instantiation via factory method failed; nested exception is org.springframework.beans.BeanInstantiationException: Failed to instantiate [org.springframework.ws.wsdl.wsdl11.DefaultWsdl11Definition]: Factory method 'defaultWsdl11Definition' threw exception; nested exception is java.lang.NullPointerException
and a bit below:

Caused by: java.lang.NullPointerException: null at org.springframework.xml.xsd.SimpleXsdSchema.getTargetNamespace(SimpleXsdSchema.java:94) ~[spring-xml-3.0.3.RELEASE.jar!/:na] at com.mycompany.WebServiceConfig.defaultWsdl11Definition(WebServiceConfig.java:66) ~[classes!/:0.0.1]

I make the things work with calling the SimpleXsdSchema::afterPropertiesSet which is not somehow called upon the bean instantiation. Hard to say what happens. However editing the method like this makes the schemas work together:

@Override
public XsdSchema[] getXsdSchemas() {
    SimpleXsdSchema[] schemaArray = new SimpleXsdSchema[] {
            new SimpleXsdSchema(new ClassPathResource("xsd/schemaA.xsd")),
            new SimpleXsdSchema(new ClassPathResource("xsd/schemaB.xsd"))
    };

    for (SimpleXsdSchema schema : schemaArray) {
        try {
            schema.afterPropertiesSet();
        } catch (ParserConfigurationException | IOException | SAXException e) { /* ...*/}
    }       
    return schemaArray;
}

Does anyone know what happens? Why passing the XsdSchema and XsdSchemaCollection doesn't behave equally even they are supposed to do according to DefaultWsdl11Definition?

JAXB difference between XsdSchema and XsdSchemaCollection while creating the DefaultWsdl11Definition bean

0 Answers0