dataunformatfilter.java

来自「cwbbs 云网论坛源码」· Java 代码 · 共 172 行

package cn.js.fan.util;


import java.util.Stack;

import org.xml.sax.Attributes;
import org.xml.sax.SAXException;
import org.xml.sax.XMLReader;



class DataUnformatFilter extends XMLFilterBase
{

    
    
    

    
    public DataUnformatFilter()
    {
    }

    
    public DataUnformatFilter(XMLReader xmlreader)
    {
        super(xmlreader);
    }

    
    
    

    
    public void reset ()
    {
        state = SEEN_NOTHING;
        stateStack = new Stack();
        whitespace = new StringBuffer();
    }

    
    
    

    
    public void startDocument ()
    throws SAXException
    {
        reset();
        super.startDocument();
    }

    
    public void startElement (String uri, String localName,
                              String qName, Attributes atts)
    throws SAXException
    {
        clearWhitespace();
        stateStack.push(SEEN_ELEMENT);
        state = SEEN_NOTHING;
        super.startElement(uri, localName, qName, atts);
    }

    
    public void endElement (String uri, String localName, String qName)
    throws SAXException
    {
        if (state == SEEN_ELEMENT) {
            clearWhitespace();
        } else {
            emitWhitespace();
        }
        state = stateStack.pop();
        super.endElement(uri, localName, qName);
    }

    
    public void characters (char ch[], int start, int length)
    throws SAXException
    {
        if (state != SEEN_DATA) {

            
            int end = start + length;
            while (end-- > start) {
                if (!isXMLWhitespace(ch[end]))
                    break;
            }

            
            if (end < start) {
                saveWhitespace(ch, start, length);
            } else {
                state = SEEN_DATA;
                emitWhitespace();
            }
        }

        
        if (state == SEEN_DATA) {
            super.characters(ch, start, length);
        }
    }

     
    public void ignorableWhitespace (char ch[], int start, int length)
    throws SAXException
    {
        emitWhitespace();
        
    }

    
    public void processingInstruction (String target, String data)
    throws SAXException
    {
        emitWhitespace();
        super.processingInstruction(target, data);
    }

    
    
    

    
    protected void saveWhitespace (char[] ch, int start, int length) {
        whitespace.append(ch, start, length);
    }

    
    protected void emitWhitespace ()
    throws SAXException
    {
        char[] data = new char[whitespace.length()];
        if (whitespace.length() > 0) {
            whitespace.getChars(0, data.length, data, 0);
            whitespace.setLength(0);
            super.characters(data, 0, data.length);
        }
    }

    
    protected void clearWhitespace () {
        whitespace.setLength(0);
    }

    
    private boolean isXMLWhitespace (char c)
    {
        return c == ' ' || c == '\t' || c == '\r' || c == '\n';
    }

    
    
    

    private static final Object SEEN_NOTHING = new Object();
    private static final Object SEEN_ELEMENT = new Object();
    private static final Object SEEN_DATA = new Object();


    
    
    

    private Object state = SEEN_NOTHING;
    private Stack stateStack = new Stack();

    private StringBuffer whitespace = new StringBuffer();
}