cz.vutbr.web.csskit.ElementUtil Maven / Gradle / Ivy

Go to download

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

jStyleParser is a CSS parser written in Java. It has its own application interface that is designed to allow an efficient CSS processing in Java and mapping the values to the Java data types. It parses CSS 2.1 style sheets into structures that can be efficiently assigned to DOM elements. It is intended be the primary CSS parser for the CSSBox library. While handling errors, it is user agent conforming according to the CSS specification.

There is a newer version: 1.20-p9

Show newest version

package cz.vutbr.web.csskit;

import java.util.ArrayList;
import java.util.Collection;
import java.util.Collections;
import java.util.HashSet;
import java.util.Set;

import org.w3c.dom.Element;
import org.w3c.dom.NamedNodeMap;
import org.w3c.dom.Node;

import cz.vutbr.web.css.Selector;

public class ElementUtil {

	public static final String CLASS_DELIM = " ";
	public static final String CLASS_ATTR = "class";
	public static final String ID_ATTR = "id";
	
	public static String getAttribute(Element e, String name)
	{
	    return e.hasAttribute(name) ? e.getAttribute(name) : "";
	}
	
	public static Collection elementClasses(Element e) 
	{
	    if (e.hasAttribute(CLASS_ATTR))
	    {
    		String classNames = getAttribute(e, CLASS_ATTR);
    		
    		Collection list = new ArrayList();
    		for (String cname : classNames.toLowerCase().split(CLASS_DELIM)) 
    		{
    			cname = cname.trim();
    			if(cname.length() > 0)
    				list.add(cname);
    		}
    		return list;
	    }
	    else
	        return Collections.emptyList();
	}
	
	public static boolean matchesClassOld(Element e, String className) 
	{
        if (e.hasAttribute(CLASS_ATTR))
        {
            String classNames = getAttribute(e, CLASS_ATTR).toLowerCase();
            int len = className.length();
    	    int start = classNames.indexOf(className.toLowerCase());
    	    if (start == -1)
    	        return false;
    	    else
    	        return ((start == 0 || Character.isWhitespace(classNames.charAt(start - 1))) &&
    	                (start + len == classNames.length() || Character.isWhitespace(classNames.charAt(start + len))));
        }
        else
            return false;
	}
	
	public static boolean matchesClass(Element e, String className)
    {
        if (e.hasAttribute(CLASS_ATTR))
        {
            String classNames = getAttribute(e, CLASS_ATTR).toLowerCase();
            String search = className.toLowerCase();
            int len = className.length();
            int lastIndex = 0;
            
            while ((lastIndex = classNames.indexOf(search, lastIndex)) != -1) {
                if ((lastIndex == 0 || Character.isWhitespace(classNames.charAt(lastIndex - 1))) &&
                        (lastIndex + len == classNames.length() || Character.isWhitespace(classNames.charAt(lastIndex + len)))) {
                    return true;
                }
                lastIndex += len;
            }
            return false;
        }
        else
            return false;
    }

	
	public static String elementID(Element e) 
	{
		String id = getAttribute(e, ID_ATTR);
		return id;
	}
	
	public static boolean matchesID(Element e, String id) 
	{
		return id.equalsIgnoreCase(elementID(e));
	}
	
	public static String elementName(Element e) 
	{
		String name = e.getNodeName();
		return name;
	}
	
	public static boolean matchesName(Element e, String name)
	{
		if (name == null)
		    return false;
		else
		    return name.equalsIgnoreCase(elementName(e));
	}
	
	public static boolean matchesAttribute(Element e, String namespaceURI, String localName, String value, Selector.Operator o) 
	{
		if (namespaceURI == null) {
			NamedNodeMap attributes = e.getAttributes();
			Set namespaces = new HashSet();
			for (int i = 0; i < attributes.getLength(); i++) {
				Node attr = attributes.item(i);
				String attrNS = attr.getNamespaceURI();
				if (attrNS == null) attrNS = "";
				namespaces.add(attrNS);
			}
			for (String ns : namespaces)
				if (matchesAttribute(e, ns, localName, value, o))
					return true;
			return false;
		}
		String attributeValue = namespaceURI.equals("") ? e.getAttribute(localName) : e.getAttributeNS(namespaceURI, localName);
	    if (attributeValue.length() >  0 && o != null)
	    {
    		switch(o) {
        		case EQUALS:
        			return attributeValue.equals(value);
        		case INCLUDES:
        		    if (value.isEmpty() || containsWhitespace(value))
        		        return false;
        		    else
        		    {
            			attributeValue = " " + attributeValue + " ";
            			return attributeValue.matches(".* " + value + " .*");
        		    }
        		case DASHMATCH:
        			return attributeValue.matches("^" + value + "(-.*|$)");
        		case CONTAINS:
        			return !value.isEmpty() && attributeValue.matches(".*" + value + ".*");
        		case STARTSWITH:
        			return !value.isEmpty() && attributeValue.matches("^" + value + ".*");
                case ENDSWITH:
                    return !value.isEmpty() && attributeValue.matches(".*" + value + "$");
        		default:
        			return true;
    		}
	    }
	    else
	        return false;
	}
	
	private static boolean containsWhitespace(String s)
	{
	    for (int i = 0; i < s.length(); i++)
	    {
	        if (Character.isWhitespace(s.charAt(i)))
	                return true;
	    }
	    return false;
	}
	
}