class StandardClassappendTagProcessor
        extends AbstractStandardExpressionAttributeTagProcessor
        implements IAttributeDefinitionsAware {

    public static final int PRECEDENCE = 1100;
    public static final String ATTR_NAME = "classappend";
    public static final String TARGET_ATTR_NAME = "class";

    private static final TemplateMode TEMPLATE_MODE = TemplateMode.HTML;

    private AttributeDefinition targetAttributeDefinition;




    public StandardClassappendTagProcessor(final String dialectPrefix) {
        super(TEMPLATE_MODE, dialectPrefix, ATTR_NAME, PRECEDENCE, true, false);
    }




    public void setAttributeDefinitions(final AttributeDefinitions attributeDefinitions) {
        Validate.notNull(attributeDefinitions, "Attribute Definitions cannot be null");
        // We precompute the AttributeDefinition of the target attribute in order to being able to use much
        // faster methods for setting/replacing attributes on the ElementAttributes implementation
        this.targetAttributeDefinition = attributeDefinitions.forName(TEMPLATE_MODE, TARGET_ATTR_NAME);
    }




    @Override
    protected final void doProcess(
            final ITemplateContext context,
            final IProcessableElementTag tag,
            final AttributeName attributeName, final String attributeValue,
            final Object expressionResult,
            final IElementTagStructureHandler structureHandler) {<FILL_FUNCTION_BODY>}


}


        String newAttributeValue =
                EscapedAttributeUtils.escapeAttribute(getTemplateMode(), expressionResult == null ? null : expressionResult.toString());

        // If we are not adding anything, we'll just leave it untouched
        if (newAttributeValue != null && newAttributeValue.length() > 0) {

            final AttributeName targetAttributeName = this.targetAttributeDefinition.getAttributeName();

            if (tag.hasAttribute(targetAttributeName)) {
                final String currentValue = tag.getAttributeValue(targetAttributeName);
                if (currentValue.length() > 0) {
                    newAttributeValue = currentValue + ' ' + newAttributeValue;
                }
            }

            StandardProcessorUtils.setAttribute(structureHandler, this.targetAttributeDefinition, TARGET_ATTR_NAME, newAttributeValue);

        }

    
<methods><variables>private final non-sealed org.thymeleaf.standard.expression.StandardExpressionExecutionContext expressionExecutionContext,private final non-sealed boolean removeIfNoop