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
Note |
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Since 2.1, these annotations are provided by the Convention Plugin. Codebehind and Zero Config plugins are deprecated from 2.1 on. |
Action annotations are available when the framework scans the classpath for Action classes, rather than specifying individual mappings through XML configuration. See the Convention Plugin page for information on how to set up classpath scanning to allow the use of Action annotations.
Annotation | Description |
---|---|
Group of @Action annotations, maps multiple URLs to the same action | |
Defines the URL of an action | |
Gropup of @InterceptorRef annotations | |
Interceptor, or interceptor stack to be applied to at action | |
Group of @Result annotations | |
Defines a result for an action | |
Set the path of the action URL (used to overwrite the default) | |
Set where the results are located (used to overwrite the default) | |
Set the parent package of the actions (used to overwrite the default) | |
Group of @ExceptionMapping annotations | |
Defines an exception mapping |
Workflow Annotations
Annotation | Description |
---|---|
Defines what method to execute, or result to be returned if there are validation errors |
Interceptor Annotations
To use these annotations, you have to specify the AnnotationWorkflowInterceptor to your interceptor stack.
Annotation | Description |
---|---|
Marks a action method that needs to be executed after the result. | |
Marks a action method that needs to be executed before the main action method. | |
Marks a action method that needs to be executed before the result. |
Validation Annotations
To use annotation-based validation,
Currently only in beta-status, an xwork-tiger project exists that is starting to add some basic J2SE 5 ("Tiger") support to WebWork. Currently, the only Java 5 implementation in xwork-tiger.jar is a Map and Collection support using generics.
In short, instead of specifying the types found in collections and maps as documented in Type Conversion, the collection's generic type is used. This means you most likely don't need any ClassName-conversion.properties files.
NOTE: This is a work in progress and not yet finished! More compex examples will follow. For now, have a look at the unit tests with the xwork-tiger project path.
Type Conversion Annotations
If you want to use annotation based type conversion, you have to annotate the class or interface with the Conversion Annotation.
Currently runtime evaluation for these annotations is not supported. This feature will be added in the near future.
For now you have to run the apt target via ant (TODO: not yet in CVS).
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Conversion
The Conversion annotation must be applied at Type level.
Parameter | Required | Default | Notes |
---|---|---|---|
conversion | no |
| Used for Type Conversions being applied at Type level. |
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TypeConversion
Parameter | Required | Default | Notes |
---|---|---|---|
property | no | The annotated property name | The optional property name used within TYPE or PACKAGE level annotations. |
type | no | ConversionType.CLASS | Enum value of ConversionType. Determines whether the conversion should be applied at application or class level. |
converter | yes |
| The class of the TypeConverter to be used as converter. |
rule | no | ConversionRule.PROPERTY | Enum value of ConversionRule. The ConversionRule can be a property, a Collection or a Map. |
The TypeConversion annotation can be applied at property and method level.
Example:
...
@Conversion()
public class ConversionAction implements Action {
private String convertInt;
private String convertDouble;
private List users = null;
private HashMap keyValues = null;
@TypeConversion(type = ConversionType.APPLICATION, converter = XWorkBasicConverter.class)
public void setConvertInt( String convertInt ) {
this.convertInt = convertInt;
}
@TypeConversion(converter = XWorkBasicConverter.class)
public void setConvertDouble( String convertDouble ) {
this.convertDouble = convertDouble;
}
@TypeConversion(rule = ConversionRule.COLLECTION, converter = String.class)
public void setUsers( List users ) {
this.users = users;
}
@TypeConversion(rule = ConversionRule.MAP, converter = BigInteger.class)
public void setKeyValues( HashMap keyValues ) {
this.keyValues = keyValues;
}
@TypeConversion(type = ConversionType.APPLICATION, property = "java.util.Date", converter = XWorkBasicConverter.class)
public String execute() throws Exception {
return SUCCESS;
}
}
Validation Annotations
If you want to use annotation based validation, you have to annotate the class or interface with Validation Annotation.
These are the standard validator annotations that come with XWork-tiger:
- #ConversionErrorFieldValidator
- #DateRangeFieldValidator
- #EmailValidator
- #ExpressionValidator
- #FieldExpressionValidator
- #IntRangeFieldValidator
- #RegexFieldValidator
- #RequiredFieldValidator
- #RequiredStringValidator
- #StringLengthFieldValidator
- #StringRegexValidator
- #UrlValidator
- #VisitorFieldValidator
...
Validations
If you want to use several annotations of the same type, these annotation must be nested within the @Validations() annotation.
The possible parameters for @Validations() are as followed:
Parameter | Required | Notes |
---|---|---|
requiredFields | no | Add list of RequiredFieldValidators |
customValidators | no | Add list of CustomValidators |
conversionErrorFields | no | Add list of ConversionErrorFieldValidators |
dateRangeFields | no | Add list of DateRangeFieldValidators |
emails | no | Add list of EmailValidators |
fieldExpressions | no | Add list of FieldExpressionValidators |
intRangeFields | no | Add list of IntRangeFieldValidators |
requiredFields | no | Add list of RequiredFieldValidators |
requiredStrings | no | Add list of RequiredStringValidators |
stringLengthFields | no | Add list of StringLengthFieldValidators |
urls | no | Add list of UrlValidators |
visitorFields | no | Add list of VisitorFieldValidators |
stringRegexs | no | Add list of StringRegexValidator |
regexFields | no | Add list of RegexFieldValidator |
expressions | no | Add list of ExpressionValidator |
...
@Validations(
requiredFields =
{@RequiredFieldValidator(type = ValidatorType.SIMPLE, fieldName = "customfield", message = "You must enter a value for field.")},
requiredStrings =
{@RequiredStringValidator(type = ValidatorType.SIMPLE, fieldName = "stringisrequired", message = "You must enter a value for string.")},
emails =
{ @EmailValidator(type = ValidatorType.SIMPLE, fieldName = "emailaddress", message = "You must enter a value for email.")},
urls =
{ @UrlValidator(type = ValidatorType.SIMPLE, fieldName = "hreflocation", message = "You must enter a value for email.")},
stringLengthFields =
{@StringLengthFieldValidator(type = ValidatorType.SIMPLE, trim = true, minLength="10" , maxLength = "12", fieldName = "needstringlength", message = "You must enter a stringlength.")},
intRangeFields =
{ @IntRangeFieldValidator(type = ValidatorType.SIMPLE, fieldName = "intfield", min = "6", max = "10", message = "bar must be between ${min} and ${max}, current value is ${bar}.")},
dateRangeFields =
{@DateRangeFieldValidator(type = ValidatorType.SIMPLE, fieldName = "datefield", min = "-1", max = "99", message = "bar must be between ${min} and ${max}, current value is ${bar}.")},
expressions = {
@ExpressionValidator(expression = "foo > 1", message = "Foo must be greater than Bar 1. Foo = ${foo}, Bar = ${bar}."),
@ExpressionValidator(expression = "foo > 2", message = "Foo must be greater than Bar 2. Foo = ${foo}, Bar = ${bar}."),
@ExpressionValidator(expression = "foo > 3", message = "Foo must be greater than Bar 3. Foo = ${foo}, Bar = ${bar}."),
@ExpressionValidator(expression = "foo > 4", message = "Foo must be greater than Bar 4. Foo = ${foo}, Bar = ${bar}."),
@ExpressionValidator(expression = "foo > 5", message = "Foo must be greater than Bar 5. Foo = ${foo}, Bar = ${bar}.")
}
)
public String execute() throws Exception {
return SUCCESS;
}
...
RequiredFieldValidator
This validator checks that a field is non-null.
Example:
...
@RequiredFieldValidator(message = "Default message", key = "i18n.key", shortCircuit = true)
...
RequiredStringValidator
This validator checks that a String field is not empty (i.e. non-null with a length > 0).
Parameter | Required | Default | Notes |
---|---|---|---|
trim | no | true | Boolean property. Determines whether the String is trimmed before performing the length check. |
Example:
...
@RequiredStringValidator(message = "Default message", key = "i18n.key", shortCircuit = true, trim = true)
...
StringLengthFieldValidator
This validator checks that a String field is of the right length. It assumes that the field is a String.
Parameter | Required | Default | Notes |
---|---|---|---|
trim | no | true | Boolean property. Determines whether the String is trimmed before performing the length check. |
minLength | no |
| Integer property. The minimum length the String must be. |
maxLength | no |
| Integer property. The maximum length the String can be. |
If neither minLength nor maxLength is set, nothing will be done.
Example:
...
@StringLengthFieldValidator(message = "Default message", key = "i18n.key", shortCircuit = true, trim = true, minLength = "5", maxLength = "12")
...
StringRegexValidator
This validator checks that a String field matches a configure Regular Expression, if it is not an empty String.
Parameter | Required | Default | Notes |
---|---|---|---|
regex | yes | "." | String property. The Regular Expression for which to check a match. |
caseSensitive | no | true | Whether the matching of alpha characters in the expression should be done case-sensitively. |
Example:
...
@StringRegexValidator(message = "Default message", key = "i18n.key", shortCircuit = true, regex = "a regular expression", caseSensitive = true)
Annotation | Description |
---|---|
Checks if there are any conversion errors for a field. | |
Checks that a date field has a value within a specified range. | |
Checks that a double field has a value within a specified range. | |
Checks |
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EmailValidator
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that a field is a valid e-mail address |
...
. |
Example:
...
@EmailValidator(message = "Default message", key = "i18n.key", shortCircuit = true)
Validates an expression. | |
Uses an OGNL expression to perform its validator. | |
Checks |
...
UrlValidator
This validator checks that a field is a valid URL.
Example:
...
@UrlValidator(message = "Default message", key = "i18n.key", shortCircuit = true)
...
IntRangeFieldValidator
...
that a numeric field has a value within a specified range. |
Parameter | Required | Default | Notes |
---|---|---|---|
min | no |
| Integer property. The minimum the number must be. |
max | no |
| Integer property. The maximum number can be. |
If neither min nor max is set, nothing will be done.
The values for min and max must be inserted as String values so that "0" can be handled as a possible value.
Example:
...
@IntRangeFieldValidator(message = "Default message", key = "i18n.key", shortCircuit = true, min = "0", max = "42")
...
DateRangeFieldValidator
This validator checks that a date field has a value within a specified range.
Parameter | Required | Default | Notes |
---|---|---|---|
min | no |
| Date property. The minimum the date must be. |
max | no |
| Date property. The maximum date can be. |
If neither min nor max is set, nothing will be done.
Example:
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@DateRangeFieldValidator(message = "Default message", key = "i18n.key", shortCircuit = true, min = "2005/01/01", max = "2005/12/31")
...
ConversionErrorFieldValidator
This validator checks if there are any conversion errors for a field and applies them if they exist. See Type Conversion Error Handling for details.
Example:
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@ConversionErrorFieldValidator(message = "Default message", key = "i18n.key", shortCircuit = true)
...
ExpressionValidator
This validator uses an OGNL expression to perform its validation. The error message will be added to the action if the expression returns false when it is evaluated against the value stack.
Parameter | Required | Default | Notes |
---|---|---|---|
expression | yes |
| An OGNL expression that returns a boolean value. |
Example:
...
@ExpressionValidator(message = "Default message", key = "i18n.key", shortCircuit = true, expression = "an OGNL expression" )
...
FieldExpressionValidator
This validator uses an OGNL expression to perform its validation. The error message will be added to the field if the expression returns false when it is evaluated against the value stack.
Parameter | Required | Default | Notes |
---|---|---|---|
expression | yes |
| An OGNL expression that returns a boolean value. |
Example:
...
@FieldExpressionValidator(message = "Default message", key = "i18n.key", shortCircuit = true, expression = "an OGNL expression")
...
VisitorFieldValidator
The validator allows you to forward validation to object properties of your action using the objects own validation files. This allows you to use the ModelDriven development pattern and manage your validations for your models in one place, where they belong, next to your model classes. The VisitorFieldValidator can handle either simple Object properties, Collections of Objects, or Arrays.
The error message for the VisitorFieldValidator will be appended in front of validation messages added by the validations for the Object message.
Parameter | Required | Default | Notes |
---|---|---|---|
context | no | action alias | Determines the context to use for validating the Object property. If not defined, the context of the Action validation is propogated to the Object property validation. In the case of Action validation, this context is the Action alias. |
appendPrefix | no | true | Determines whether the field name of this field validator should be prepended to the field name of the visited field to determine the full field name when an error occurs. For example, suppose that the bean being validated has a "name" property. If appendPrefix is true, then the field error will be stored under the field "bean.name". If appendPrefix is false, then the field error will be stored under the field "name". |
Example:
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@VisitorFieldValidator(message = "Default message", key = "i18n.key", shortCircuit = true, context = "action alias", appendPrefix = true)
Here we see the context being overridden in the validator mapping, so the action alias context will not be propogated.
ModelDriven example:
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@VisitorFieldValidator(message = "Default message", key = "i18n.key", shortCircuit = true, context = "action alias", appendPrefix = true)
This will use the model's validation rules and any errors messages will be applied directly (nothing is prefixed because of the empty message).
Complex Examples
An Annotated Interface
- Mark the interface with @Validation()
- Apply standard or custom annoations at method level
...
@Validation()
public interface AnnotationDataAware {
void setBarObj(Bar b);
Bar getBarObj();
@RequiredFieldValidator(message = "You must enter a value for data.")
@RequiredStringValidator(message = "You must enter a value for data.")
void setData(String data);
String getData();
}
An Annotated Class
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Validates a regular expression for a field. | |
Checks that a field is non-null. | |
Checks that a String field is not empty. | |
Checks that a String field is of the right length. | |
Checks that a field is a valid URL. | |
Marker annotation for validation at Type level. | |
Used to group validation annotations. | |
Invokes the validation for a property's object type. | |
Use this annotation for your custom validator types. |
Resources
- Validation using Annotations (arsenalist)
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 |
---|---|
Marker annotation for type conversions at Type level. | |
For Collection and Map types: Create the types within the Collection or Map, if null. | |
For Generic types: Specify the element type for Collection types and Map values. | |
For Generic types: Specify the key type for Map keys. | |
For Generic types: Specify the key property name value. | |
Used for class and application wide conversion rules. |
Tiles Annotations
The Tiles Plugin provides it's own set of Annotations. They can be used to keep tiles.xml
short. Instead tiles definitions can be created by annotating actions.
Annotation | Description |
---|---|
TilesDefinition | Represents a <definition> element in tiles.xml |
TilesDefinitions | A list of TilesDefinition Annotations |
TilesPutAttribute | Represents a <put-attribute> element in tiles.xml |
TilesPutListAttribute | Represents a <put-list-attribute> element in tiles.xml |
TilesAddAttribute | Represents a <add-attribute> element in tiles.xml |
TilesAddListAttribute | Represents a <add-list-attribute> element in tiles.xml |
Next: Configuration Elements
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