com.opensymphony.xwork2.validator.validators

## Class RequiredFieldValidator

- java.lang.Object
- - com.opensymphony.xwork2.validator.validators.ValidatorSupport
  - - com.opensymphony.xwork2.validator.validators.FieldValidatorSupport
    - - com.opensymphony.xwork2.validator.validators.RequiredFieldValidator

- All Implemented Interfaces:
    FieldValidator, ShortCircuitableValidator, Validator

      public class RequiredFieldValidator
      extends FieldValidatorSupport

  RequiredFieldValidator checks if the specified field is not null.
  - fieldName - field name if plain-validator syntax is used, not needed if field-validator syntax is used

                 <validators>

               <!-- Plain Validator Syntax -->
               <validator type="required">
                   <param name="fieldName">username</param>
                   <message>username must not be null</message>
               </validator>

               <!-- Field Validator Syntax -->
               <field name="username">
                   <field-validator type="required">
                         <message>username must not be null</message>
                   </field-validator>
               </field>

           </validators>

  Author:
    rainerh

- - ### Field Summary

    - ### Fields inherited from class com.opensymphony.xwork2.validator.validators.FieldValidatorSupport

      `currentValue, fieldName, type`

    - ### Fields inherited from class com.opensymphony.xwork2.validator.validators.ValidatorSupport

      `defaultMessage, EMPTY_STRING, messageKey, stack, textProviderFactory`

  - ### Constructor Summary

    Constructors
    Constructor and Description
    `RequiredFieldValidator()`

  - ### Method Summary

    All Methods Instance Methods Concrete Methods
    Modifier and Type | Method and Description
    --- | ---
    `void` | `validate(Object object)` The validation implementation must guarantee that setValidatorContext will be called with a non-null ValidatorContext before validate is called.

    - ### Methods inherited from class com.opensymphony.xwork2.validator.validators.FieldValidatorSupport

      `getCurrentValue, getFieldName, getValidatorType, setFieldName, setValidatorType`

    - ### Methods inherited from class com.opensymphony.xwork2.validator.validators.ValidatorSupport

      `addActionError, addFieldError, getDefaultMessage, getFieldValue, getMessage, getMessageKey, getMessageParameters, getValidatorContext, isShortCircuit, parse, setDefaultMessage, setMessageKey, setMessageParameters, setShortCircuit, setTextProviderFactory, setValidatorContext, setValueStack`

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

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

    - ### Methods inherited from interface com.opensymphony.xwork2.validator.Validator

      `getDefaultMessage, getMessage, getMessageKey, getMessageParameters, getValidatorContext, setDefaultMessage, setMessageKey, setMessageParameters, setValidatorContext, setValueStack`

- - ### Constructor Detail

    - #### RequiredFieldValidator

          public RequiredFieldValidator()

  - ### Method Detail

    - #### validate

          public void validate(Object object)
                        throws ValidationException

      Description copied from interface: `Validator`
      The validation implementation must guarantee that setValidatorContext will be called with a non-null ValidatorContext before validate is called.
      Parameters:
        `object` - the object to be validated.
      Throws:
        `ValidationException` - is thrown if there is validation error(s).

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