String format.
String form of a message parameter
value and the corresponding custom Java type T.
Conversion of message parameter values injected via @PathParam,
@QueryParam, @MatrixParam,
@FormParam, @CookieParam and
@HeaderParam is supported.
JAX-RS implementations MUST support the ParamConverter mechanism for all Java types. If a
ParamConverter is available for a type, it MUST be preferred over all other conversion strategies mentioned
in section 3.2 (i.e. single String argument constructor, static valueOf or fromString
methods, etc.).
By default, when used for injection of parameter values, a selected ParamConverter instance MUST be used
eagerly by a JAX-RS runtime to convert any default value in the resource or provider model, that
is during the application deployment, before any value – default or otherwise – is actually required.
This conversion strategy ensures that any errors in the default values are reported as early as possible. This
default behavior may be overridden by annotating the ParamConverter implementation class with a @Lazy annotation. In such case any default value conversion delegated to the @Lazy-annotated converter
will be deferred to a latest possible moment (i.e. until the injection of such default value is required).
Note
A service implementing this contract is not recognized as a registrable JAX-RS extension provider. Instead, a
ParamConverterProvider instance responsible for providing ParamConverter instances has to be
registered as one of the JAX-RS extension providers.
| Modifier and Type | Class and Description |
|---|---|
| public static @interface | ParamConverter.
Mandates that a conversion of any |
| Modifier and Type | Method and Description |
|---|---|
| public T | Returns: the newly created instance ofT.the string value. value)Parse the supplied value and create an instance of |
| public String | Returns: a String representation of the value.the value of type value)T.Convert the supplied value to a String. |
| fromString | back to summary |
|---|---|
| public T fromString(String value) Parse the supplied value and create an instance of
| |
| toString | back to summary |
|---|---|
| public String toString(T value) Convert the supplied value to a String. This method is reserved for future use. Proprietary JAX-RS extensions may leverage the method. Users should be aware that any such support for the method comes at the expense of producing non-portable code.
| |
default value delegated to a parameter
converter annotated with @Lazy annotation SHOULD occur only once the value is actually required (e.g. to be
injected for the first time).