w3c.css.parser.AtRule Maven / Gradle / Ivy

Go to download

Show more of this group Show more artifacts with this name
Show all versions of cssvalidator Show documentation

Backend for the W3C CSS Validation Service

There is a newer version: 1.0.8

//
// $Id$
// From Philippe Le Hegaret ([email protected])
//
// (c) COPYRIGHT MIT and INRIA, 1997.
// Please first read the full copyright statement in file COPYRIGHT.html
/*
 * AtRule.java
 * $Id$
 */
package org.w3c.css.parser;

/**
 * @author Philippe Le Hegaret
 * @version $Revision$
 */
public abstract class AtRule {

    /**
     * Returns the at rule keyword
     */
    public abstract String keyword();

    /**
     * The second must be exactly the same of this one
     */
    public abstract boolean canApply(AtRule atRule);

    /**
     * The second must only match this one
     */
    public abstract boolean canMatch(AtRule atRule);

    public abstract boolean isEmpty();

    /**
     * By default, lookupPrefix is not empty.
     * It is used to return (or not) a prefix used to lookup
     * properties. This should be used only if there are
     * properties specific to that at-rule.
     *
     * @return a string
     * @see .isPropertyLookupStrict
     *      
     *      Example is @font-face.src,
     *      prefix is 'font-face',
     *      specific property is 'src', and is not a CSS-wide property
     */
    public String lookupPrefix() {
        return keyword();
    }

    /**
     * When a prefix is defined, this stops or not looking up property
     * in the general set of properties.
     * 

     * Example 1:
     *
     * @return a boolean, true if the lookup has to be strict
     * @page arule, z-index property.
     * 

     * prefix should be @page, as it contain a @page specific property: 'page'
     * and lookup should not be strict to allow looking up 'z-index' without having
     * to duplicate as @page.z-index
     * 

     * Example 2:
     * @font-face atrule color property.
     * 
     * The prefix is 'font-face' as specific properties exist (like 'src'),
     * however 'color' and other css-wide properties are not valid there,
     * so lookup should be strict.
     */
    public boolean isPropertyLookupStrict() {
        return true;
    }
}