ParameterScriptAssert (Red Hat JBoss Enterprise Application Platform 8.0.0.GA public API)

```
@Documented
@Constraint(validatedBy={})
@Target({CONSTRUCTOR,METHOD})
@Retention(RUNTIME)
@Repeatable(List.class)
public @interface ParameterScriptAssert
```
A method-level constraint, that evaluates a script expression against the annotated method or constructor. This constraint can be used to implement validation routines that depend on several parameters of the annotated executable.

Script expressions can be written in any scripting or expression language, for which a JSR 223 ("Scripting for the Java^TM Platform") compatible engine can be found on the classpath. To refer to a parameter within the scripting expression, use its name as obtained by the active ParameterNameProvider. The default provider will return the actual parameter names, if the -parameters compiler option has been enabled, and arg0, arg1 etc. otherwise.

The following listing shows an example using the JavaScript engine which comes with the JDK:
```
 @ParameterScriptAssert(script = "start.before(end)", lang = "javascript")
 public void createEvent(Date start, Date end) { ... }
 
 
```
Can be specified on any method or constructor.
Author:

Gunnar Morling

- Required Element Summary
  
  Required Elements
  Modifier and Type Required Element Description
  
  String lang
  
  String script
- Optional Element Summary
  
  Optional Elements
  Modifier and Type Optional Element Description
  
  Class<?>[] groups
  
  String message
  
  Class<? extends Payload>[] payload

- Element Detail
  - lang
```
String lang
```
    Returns:
    
    The name of the script language used by this constraint as expected by the JSR 223 ScriptEngineManager. A ConstraintDeclarationException will be thrown upon script evaluation, if no engine for the given language could be found.
- - script
```
String script
```
    Returns:
    
    The script to be executed. The script must return Boolean.TRUE, if the executable parameters could successfully be validated, otherwise Boolean.FALSE. Returning null or any type other than Boolean will cause a ConstraintDeclarationException upon validation. Any exception occurring during script evaluation will be wrapped into a ConstraintDeclarationException, too. Within the script, the validated parameters can be accessed using their names as retrieved from the active ParameterNameProvider.
- - message
```
String message
```
    Default:
    
    "{org.hibernate.validator.constraints.ParametersScriptAssert.message}"
- - groups
```
Class<?>[] groups
```
    Default:
    
    {}
- - payload
```
Class<? extends Payload>[] payload
```
    Default:
    
    {}