fragmentstreamreader.java

Xfire文件 用于开发web service 的一个开源工具 很好用的

package org.codehaus.xfire.util.stax;

import javax.xml.stream.XMLStreamException;
import javax.xml.stream.XMLStreamReader;

/**
 * Wraps a XMLStreamReader and provides START_DOCUMENT and END_DOCUMENT events.
 * 
 * @author <a href="mailto:[e-mail]">Dan Diephouse</a>
 */
public class FragmentStreamReader
    extends DepthXMLStreamReader
{
    private boolean startDoc = false;
    private boolean startElement = false;
    private boolean middle = true;
    private boolean endDoc = false;

    private int depth;
    private int current = -1;
    private boolean filter = true;
    private boolean advanceAtEnd = true;
    
    public FragmentStreamReader(XMLStreamReader reader)
    {
        super(reader);
    }    
   
    public int getEventType()
    {
        return current;
    }

    public boolean hasNext()
        throws XMLStreamException
    {
        if (!startDoc) 
        {
            return true;
        }
        
        if (endDoc) 
        {
            return false;
        }
        
        return reader.hasNext();
    }
    
    public int next()
        throws XMLStreamException
    {
        if (!startDoc) 
        {
            startDoc = true;
            current = START_DOCUMENT;
        }
        else if (!startElement) 
        {
            depth = getDepth();
            
            current = reader.getEventType();
            
            if (filter)
            {
                while(current != START_ELEMENT && depth >= getDepth() && super.hasNext())
                {
                    current = super.next();
                }
                
                filter = false;
            }
            
            startElement = true;
            current = START_ELEMENT;
        }
        else if (middle)
        {
            current = super.next();

            if (current == END_ELEMENT && getDepth() < depth)
            {
                middle = false;
            }
        }
        else if (!endDoc)
        {
            // Move past the END_ELEMENT token.
            if (advanceAtEnd) super.next();
            
            endDoc = true;
            current = END_DOCUMENT;
        }
        else
        {
            throw new XMLStreamException("Already at the end of the document.");
        }

        return current;
    }

    public boolean isAdvanceAtEnd()
    {
        return advanceAtEnd;
    }

    /**
     * Set whether or not the FragmentStreamReader should move past the END_ELEMENT
     * when it is done parsing.
     * @param advanceAtEnd
     */
    public void setAdvanceAtEnd(boolean advanceAtEnd)
    {
        this.advanceAtEnd = advanceAtEnd;
    }    

}