in src/main/java/org/apache/sling/xss/impl/style/ValidatingDocumentHandler.java [171:191]
private boolean validateProperty(String name, String lexicalValueToString) {
if ( lexicalValueToString == null )
return false;
Property property = cssPolicy.getCssRules().get(name);
if ( property == null )
return false;
if ( property.getLiterals().contains(lexicalValueToString) )
return true;
if ( property.getRegexps().stream()
.anyMatch( p -> p.matcher(lexicalValueToString).matches() ) )
return true;
if ( property.getShorthands().stream()
.anyMatch( s -> validateProperty(s, lexicalValueToString)) )
return true;
return false;
}