The short range field validator in Struts is very similar to the integer one, except it can be used only for a field of short primitive/wrapper type. This validator checks if a short field falls within a certain range. Like other Struts validators, there are two forms of using this validator:

• • XML: using type=”short” attribute in <validator> or <field-validator> elements.
  • Annotation: using @ShortRangeFieldValidator annotation type before field’s setter method or action method (plain-validator).

NOTES: Attempting to apply the short validator on a field of other types (e.g. long, int, or byte) will result in a runtime java.lang.ClassCastException.

 

1. Struts Short Range Field Validator XML

Usage:

• Field-validator syntax:
  

  <field name="fieldName">
  	<field-validator type="short">
  		<param name="param name">param value</param>
  		<message>validation error message</message>
  	</field-validator>
  </field>

   

• Plain-validator syntax:
  

  <validator type="short">
  		<param name="param name">param value</param>
  		<message>validation error message</message>
  </validator> 

 

Parameters:

Parameter name	Required	Description
fieldName		Name of the field (required if using plain validator syntax).
min	No	The minimum value to check. It won’t be checked if omitted.
max	No	The maximum value to check. It won’t be checked if omitted.
parse	No	Boolean value. If set to true, evaluate the minExpressionand maxExpression to find min/max.
minExpression	No	Expression to calculate the minimum value. It won’t be evaluated if omitted.
maxExpression	No	Expression to calculate the maximum value. It won’t be evaluated if omitted.

Struts Short Range Field Validator XML Examples:

• Field-validator example:  

  <field name="quantity">
  	<field-validator type="short">
  		<param name="min">1</param>
  		<param name="max">10</param>
  		<message>Please enter quantity between ${min} and ${max}</message>
  	</field-validator>
  </field>

   

• Omitting the minimum check:

  <field name="quantity">
  	<field-validator type="short">
  		<param name="max">10</param>
  		<message>Please enter quantity less than ${max}</message>
  	</field-validator>
  </field>

• Using minExpression and maxExpression:
  

  <field name="quantity">
  	<field-validator type="short">
  		<param name="minExpression">${minValue}</param>
  		<param name="maxExpression">${maxValue}</param>
  		<message>Please enter quantity between ${min} and ${max}</message>
  	</field-validator>
  </field> 

  
  
  
  In this case, we have to implement two methods getMinValue() and getMaxValue() in the action or JavaBean class as follows:

  public short getMinValue() {
  	return 1;
  }
  
  public short getMaxValue() {
  	return 10;
  }

   

• Plain-validator example:
  

  <validator type="short">
  	<param name="fieldName">quantity</param>
  	<param name="min">1</param>
  	<param name="max">10</param>
  	<message>Oops! Please enter quantity between ${min} and ${max}</message>
  </validator> 

 

2. Struts @ShortRangeFieldValidator Annotation

Usage: Put the @ShortRangeFieldValidatorannotation before the setter method or action method (in case of using plain-validator) in the following form:

@ShortRangeFieldValidator(param1 = "param 1 value", param2 = "param 2 value", ...)

Parameters:

Parameter name	Required	Default value	Description
message	Yes		validation error message.
key	No		i18n key for validation error message.
messageParams	No		Additional parameters to customize the message.
fieldName	No		Specifies field name in case this validator type is plain-validator.
shortCircuit	No	false	Whether this validator is short circuit.
type	No	ValidatorType.FIELD	type of the validator: field-validator (FIELD) or plain-validator (SIMPLE).
min	No		The minimum value to check.
minExpression	No		OGNL expression used to calculate the minimum value.
max	No		The maximum value to check
maxExpression	No		OGNL expression used to calculate the maximum value.
parse	No	false	Whether to evaluate the minExpressionand maxExpression to find min/max.

Struts @ShortRangeFieldValidator Annotation Examples:

• Basic field-validator:
  

  @ShortRangeFieldValidator(
  		min = "20", max = "70",
  		message = "Please enter quantity between ${min} and ${max}")
  public void setQuantity(short quantity) {
  	this.quantity = quantity;
  }

   

• Specifying i18n key for the message:
  

  @ShortRangeFieldValidator(
  		min = "20", max = "70",
  		message = "Default message",
  		key = "form.validation.quantity")
  public void setQuantity(short quantity) {
  	this.quantity = quantity;
  }

   

• Plain-validator (annotating the action method):
  

  @ShortRangeFieldValidator(
  		type = ValidatorType.SIMPLE,
  		fieldName = "quantity",
  		min = "20", max = "70",
  		message = "Please enter quantity between ${min} and ${max}"
  		)
  public String execute() {
  	return SUCCESS;
  } 

 

Related Struts Form Validation Tutorials:

• Struts Form Handling Tutorial
• Struts Form Validation Tutorial
• Struts Date Range Field Validator Example
• Struts Integer Range Field Validator Example
• Struts String Length Field Validator Example
• Struts URL Validator Example
• Struts Required Field Validator Example
• Struts Field Expression Validator Example

 

Other Struts Tutorials:

• Introduction to Struts 2 framework
• Struts beginner tutorial (Eclipse + Tomcat + XML)
• Struts Beginner Tutorial with Annotations
• Struts beginner tutorial with Convention Plugin (zero-configuration)
• How to handle exceptions in Struts
• Send e-mail with attachments in Struts
• Struts File Upload Tutorial
• Struts - Spring - Hibernate Integration Tutorial