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Added by Patrick Lightbody, last edited by Dave Newton on Feb 16, 2008  (view change) show comment

In many places, applications can use Java 5 annotations as an alternative to XML and Java properties configuration. This page serves as a reference for all annotations across the framework.

Action Annotations

Action annotations are available when the framework scans the classpath for Action classes, rather than specifying individual mappings through XML configuration. See the Zero Configuration page for information on how to set up classpath scanning to allow the use of Action annotations.

Annotation Description
Namespace Annotation Overrides the namespace of an action
ParentPackage Annotation Defines an existing configuration package for the action's package to extend
Result Annotation Defines an action Result
Results Annotation Defines multiple Results

Interceptor Annotations

To use these annotations, you have to specify the AnnotationWorkflowInterceptor to your interceptor stack.

Annotation Description
After Annotation Marks a action method that needs to be executed after the result.
Before Annotation Marks a action method that needs to be executed before the main action method.
BeforeResult Annotation Marks a action method that needs to be executed before the result.

Validation Annotations

To use annotation-based validation, annotate the class or interface with Validation Annotation.

Annotation Description
ConversionErrorFieldValidator Annotation Checks if there are any conversion errors for a field.
DateRangeFieldValidator Annotation Checks that a date field has a value within a specified range.
DoubleRangeFieldValidator Annotation Checks that a double field has a value within a specified range.
EmailValidator Annotation Checks that a field is a valid e-mail address.
ExpressionValidator Annotation Validates an expression.
FieldExpressionValidator Annotation Uses an OGNL expression to perform its validator.
IntRangeFieldValidator Annotation Checks that a numeric field has a value within a specified range.
RegexFieldValidator Annotation Validates a regular expression for a field.
RequiredFieldValidator Annotation Checks that a field is non-null.
RequiredStringValidator Annotation Checks that a String field is not empty.
StringLengthFieldValidator Annotation Checks that a String field is of the right length.
StringRegexValidator Annotation Invokes a regular expression to validate a String field.
UrlValidator Annotation Checks that a field is a valid URL.
Validation Annotation Marker annotation for validation at Type level.
Validations Annotation Used to group validation annotations.
VisitorFieldValidator Annotation Invokes the validation for a property's object type.
CustomValidator Annotation Use this annotation for your custom validator types.

Resources

Type Conversion Annotations

By default, type conversion for Maps and Collections using generics is directly supported.

In short, instead of specifying the types found in collections and maps as documented in Type Conversion, the collection's generic type is used. By using annotations, an application should be able to avoid using any ClassName-conversion.properties files.

To use annotation-based type conversion, annotate the class or interface with the Conversion Annotation.

Annotation Description
Conversion Annotation Marker annotation for type conversions at Type level.
CreateIfNull Annotation For Collection and Map types: Create the types within the Collection or Map, if null.
Element Annotation For Generic types: Specify the element type for Collection types and Map values.
Key Annotation For Generic types: Specify the key type for Map keys.
KeyProperty Annotation For Generic types: Specify the key property name value.
TypeConversion Annotation Used for class and application wide conversion rules.

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