Package org.apache.tapestry5.validator

## Class Checked

- java.lang.Object
- - org.apache.tapestry5.validator.AbstractValidator<Void,​Object>
  - - org.apache.tapestry5.validator.Checked

- All Implemented Interfaces:
    `Validator<Void,​Object>`

      public final class Checked
      extends AbstractValidator<Void,​Object>

  A validator that enforces that the value is true. This validator is not configurable.
  Since:
    5.5.0

- - ### Field Summary

    - ### Fields inherited from class org.apache.tapestry5.validator.AbstractValidator

      `javaScriptSupport`

  - ### Constructor Summary

    Constructors
    Constructor | Description
    --- | ---
    `Checked​(JavaScriptSupport javaScriptSupport, Html5Support html5Support)` |

  - ### Method Summary

    All Methods Instance Methods Concrete Methods
    Modifier and Type | Method | Description
    --- | --- | ---
    `boolean` | `isRequired()` | The exception to the rule.
    `void` | `render​(Field field, Void constraintValue, MessageFormatter formatter, MarkupWriter writer, FormSupport formSupport)` | Hook used by components to allow the validator to contribute additional attributes or (more often) client-side JavaScript (via the `FormSupport.addValidation(Field, String, String, Object)`).
    `String` | `toString()` |
    `void` | `validate​(Field field, Void constraintValue, MessageFormatter formatter, Object value)` | Invoked after the client-submitted value has been `translated` to check that the value conforms to expectations (often, in terms of minimum or maximum value).

    - ### Methods inherited from class org.apache.tapestry5.validator.AbstractValidator

      `getConstraintType, getMessageKey, getValueType`

    - ### Methods inherited from class java.lang.Object

      `clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait`

- - ### Constructor Detail

    - #### Checked

          public Checked​(JavaScriptSupport javaScriptSupport,
                         Html5Support html5Support)

  - ### Method Detail

    - #### render

          public void render​(Field field,
                             Void constraintValue,
                             MessageFormatter formatter,
                             MarkupWriter writer,
                             FormSupport formSupport)

      Description copied from interface: `Validator`
      Hook used by components to allow the validator to contribute additional attributes or (more often) client-side JavaScript (via the `FormSupport.addValidation(Field, String, String, Object)`).
      Specified by:
        `render` in interface `Validator<Void,​Object>`
      Parameters:
        `field` - the field which is currently being rendered
        `constraintValue` - the value used to constrain input
        `formatter` - validation message, in the appropriate locale
        `writer` - markup writer, allowing additional attributes to be written into the active element
        `formSupport` - used to add JavaScript

    - #### validate

          public void validate​(Field field,
                               Void constraintValue,
                               MessageFormatter formatter,
                               Object value)
                        throws ValidationException

      Description copied from interface: `Validator`
      Invoked after the client-submitted value has been `translated` to check that the value conforms to expectations (often, in terms of minimum or maximum value). If and only if the value is approved by all Validators is the value applied by the field.
      Parameters:
        `field` - the field for which a client submitted value is being validated
        `constraintValue` - the value used to constrain
        `formatter` - Validation messages, in the appropriate locale
        `value` - the translated value supplied by the user
      Throws:
        `ValidationException` - if the value violates the constraint

    - #### isRequired

          public boolean isRequired()

      The exception to the rule.
      Specified by:
        `isRequired` in interface `Validator<Void,​Object>`
      Overrides:
        `isRequired` in class `AbstractValidator<Void,​Object>`

    - #### toString

          public String toString()

      Overrides:
        `toString` in class `Object`