code: protected void validate(String operationType) throws Exception
  	{
  		super.validate(operationType);
  
  		MPSString image_name_validator = new MPSString();
  		image_name_validator.setConstraintIsReq(MPSConstants.MODIFY_CONSTRAINT, true);
  		image_name_validator.setConstraintMaxStrLen(MPSConstants.MODIFY_CONSTRAINT, 128);
  		image_name_validator.setConstraintMinStrLen(MPSConstants.MODIFY_CONSTRAINT, 1);
  		image_name_validator.validate(operationType, image_name, "\"image_name\"");
  		
  		MPSString xen_version_validator = new MPSString();
  		xen_version_validator.validate(operationType, xen_version, "\"xen_version\"");
  		
  	}
docs: <pre>
  Performs generic data validation for the operation to be performed
  </pre>