[SOLVED] Oval with expression language

Oval with expression language

I am using Oval http://oval.sourceforge.net/ for java bean validations and I'm getting an exception when using the expression language features.

My code looks like this:

@NotNull(errorCode = "paymentCard.number.invalid", message = "Required", when = "_this.cardType != null")
private String cardNumber;

and the outcome is

WARNING: Cannot determine constraint when formula based on annotation $Proxy10
java.lang.ArrayIndexOutOfBoundsException: 1
    at net.sf.oval.AbstractCheck.setWhen(AbstractCheck.java:276)
    at net.sf.oval.configuration.annotation.AbstractAnnotationCheck.configure(AbstractAnnotationCheck.java:183)
    at net.sf.oval.configuration.annotation.AnnotationsConfigurer.initializeCheck(AnnotationsConfigurer.java:323)
    at net.sf.oval.configuration.annotation.AnnotationsConfigurer.configureFieldChecks(AnnotationsConfigurer.java:143)
    at net.sf.oval.configuration.annotation.AnnotationsConfigurer.getClassConfiguration(AnnotationsConfigurer.java:294)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:197)
31-Jul-2013 18:04:51 net.sf.oval.internal.Log info
INFO: Available ScriptEngine language names: [[js, rhino, JavaScript, javascript, ECMAScript, ecmascript]]

I don't know why this is happening, can anybody help me?

Thanks in advance

Solution

You have to write firstly the prefix to indicate Oval which implementation use, but it's also necessary to register the Expression Language implementation you want to use in your project. Without this step Oval won't be able to figure out what implementation you are using to resolve your EL expressions.

private static final Validator VALIDATOR = new Validator();
static {
    VALIDATOR.getExpressionLanguageRegistry().registerExpressionLanguage("js",
            new ExpressionLanguageJavaScriptImpl());
}