11.4. Supported Validators
11.4.1. Java
11.4.1.1. Use a Java Validator
Procedure 11.2. Create a Java Validator
- Implement the
org.switchyard.validate.Validatorinterface. - Add a <validate.java> definition to your
switchyard.xmlfile. - Alternatively, annotate one or more methods to your Java class with @Validator:
@Named("MyValidatorBean") public class MyValidator { @Validator(name = "{urn:switchyard-quickstart-demo:orders:1.0}submitOrder") public ValidationResult validate(Element from) { // handle validation here } }When using the @Validator annotation, the SwitchYard Maven plug-in automatically generates the <validate.java> definitions for you and add them to theswitchyard.xmlfile packaged in your application.The Java class above produces this <validate.java> definition:<validate.java bean="MyValidatorBean" name="{urn:switchyard-quickstart-demo:orders:1.0}submitOrder"/>
11.4.1.2. Java Validator Reference
The optional name element of the @Validator annotation can be used to specify the qualified type name used during validator registration. If not supplied, the full class name of the method parameter is used as the type.
The CDI bean name specified by @Named annotation is used to resolve validator class. If you fail to specify it, then the validator's class name is used instead:
<validates>
<validate.java class="org.switchyard.quickstarts.demos.orders.MyValidator"
name="{urn:switchyard-quickstart-demo:orders:1.0}submitOrder"/>
</transforms>
Note
Each of the <validate.java> definitions have either a bean attribute or a class attribute. These two attributes are mutually exclusive.
11.4.1.3. ValidationResult
ValidationResult is a simple interface which represents the result of validation. It has two methods,
isValid() and getDetail().
11.4.1.4. Java Validation Failure
If Java validation fails, the message exchange process stops immediately and a
HandlerException is thrown along with a validation failure message which is returned by ValidationResult.getDetail(). Make sure that you return a ValidationResult with failure detail message when you want to indicate a validation failure in your Java Validator, instead of throwing a RuntimeException.
11.4.1.5. ValidationResult Properties
isValid() returns whether the validation succeeded or not. _getDetail() returns an error message if validation fails.
package org.switchyard.validate;
public interface ValidationResult {
boolean isValid();
String getDetail();
}
There are three convenience methods available for
org.switchyard.validate.BaseValidator. These are validResult(), invalidResult() and invalidResult(String) Use them to generate ValidationResult objects.
11.4.2. XML
11.4.2.1. Use an XML Validator
The XML validator allows you to perform a validation against its schema definition. It support DTD, XML_SCHEMA, and RELAX_NG schema types. You can configure an XML validator by specifying the schema Type, the name QName, and the path to the schema file. Here is an example:
<validate.xml schemaType="XML_SCHEMA" name="{urn:switchyard-quickstart:validate-xml:0.1.0}order" failOnWarning="true" namespaceAware="true">
<schemaFiles>
<entry file="/xsd/orders.xsd"/>
</schemaFiles>
<schemaCatalogs>
<entry file="/xsd/catalog.xml"/>
</schemaCatalogs>
</validate.xml>
If you specify the failOnWarning attribute as true, the validation fails if any warning is detected during validation. If the XML content to be validated has namespace prefix, then you need to specify namespaceAware as true.
11.4.2.2. XML Catalog
You can use XML catalog to decouple the schema file location from schema definition itself. This schema is
orders.xsd which has a import element. It refers to logical name orders.base by the schemaLocation attribute:
<schema xmlns="http://www.w3.org/2001/XMLSchema"
targetNamespace="urn:switchyard-quickstart:validate-xml:0.1.0"
xmlns:base="urn:switchyard-quickstart:validate-xml-base:0.1.0"
xmlns:orders="urn:switchyard-quickstart:validate-xml:0.1.0">
<import namespace="urn:switchyard-quickstart:validate-xml-base:0.1.0" schemaLocation="orders.base"/>
...
Here is the catalog.xml file that resolves actual schema location from logical name orders.base:
<catalog xmlns="urn:oasis:names:tc:entity:xmlns:xml:catalog">
<system systemId="orders.base" uri="orders-base.xsd"/>
</catalog>
11.4.2.3. XML Validation Failure
If XML validation fails, the message exchange process stops immediately and a
HandlerException is thrown along with a validation failure message. XMLValidator collects a set of validation failures through the SAX ErrorHandler, and uses the getMessage() of each received SAXParseException as a failure detail with extracting root cause, if exists.
