xjsthread.java

XBrowser是一个完全免费并且开源的Web浏览器

/****************************************************************
*              XBrowser  -  eXtended web Browser                *
*                                                               *
*           Copyright (c) 2000-2001  Armond Avanes              *
*     Refer to ReadMe & License files for more information      *
*                                                               *
*                                                               *
*                 By: Uladzimir V. Kavalchuk                    *
*               [e-mail]                 *
*               http://xbrowser.sourceforge.net/                *
*****************************************************************/
package xbrowser.renderer.custom.js;

import java.util.*;
import java.net.*;
import java.io.*;
import javax.swing.text.Element;

import xbrowser.renderer.*;
import xbrowser.renderer.custom.*;

import org.mozilla.javascript.*;

public class XJSThread extends Thread implements XIScriptConsumer {

    public XJSThread( URL _base, XHTMLDocument doc) {
        base = _base;
        window = new XJSWindow( doc, doc.getWindow());
        document = new XJSDocument( doc, window);
		window.setDocument( document);

        scriptItems = new LinkedList();
		_scripts = new LinkedList();
    }

	public XJSWindow getWindow() {
	    return window;
	}

	// XIScriptConsumer implementation {
    public synchronized void addScript( String script, Element startTag) {
        scriptItems.addLast( script);
		_scripts.addLast( startTag);
        notify();
		if( JS_SYNCHRONIZE)
		try {
		    wait();
		} catch( InterruptedException e) {}
    }

    public synchronized void addScriptLink( String src) {
        try {
            scriptItems.addLast( new URL( base, src));
		    _scripts.addLast( null);
        } catch( MalformedURLException exc) {
             // We must also say user that this page has bad js links...
             XRendererSupport.getContext().getLogger().error( this, exc);
        }
        notify();
		if( JS_SYNCHRONIZE)
		try {
		    wait();
		} catch( InterruptedException e) {}
    }

	public XDOM getSink() {
	    return document;
	}

	/** document.write() requires inserting text after </script ;&gt tag;
	 *  but JS portion is taken BEFORE end tag occurs. This function is a
	 *  workaround; may be eliminated later. */
	public synchronized void setEndScriptTag( Element startTag, Element endTag) {
	    int len = _scripts.size();
	    for( int i = 0; i < len; i++) {
			 if( _scripts.get( i) == startTag)
				 _scripts.set( i, endTag);
		}
	}

	public void endParsing() {
	    document.endParsing(); // notify
	}
	// } XIScriptConsumer end, implementated

    protected void prepare() {
       ctx = Context.enter();
       ctx.initStandardObjects( window);
       XJSDocument.UNDEFINED = ctx.getUndefinedValue();

       try {
           window.defineSelf();
           if( DEBUG_THREAD)
           XRendererSupport.getContext().getLogger().message( this, "JS Thread prepared");
       } catch( Exception pex) {
           XRendererSupport.getContext().getLogger().message( this, "JS Thread failed during prepare:");
           XRendererSupport.getContext().getLogger().error( this, pex);
       }
    }

    protected void cleanup() {
       Context.exit();
    }

    public void run() {
        Object portion = null;
        prepare();

        while( ! isInterrupted()) {
            synchronized( this) {
                try {
					if( scriptItems.isEmpty())
                        wait(); // wait notifications of next portion
                } catch( InterruptedException ie) {
                    if( DEBUG_THREAD)
						XRendererSupport.getContext().getLogger().error( this, "Interrupt worked!");
                    break;
                }
                if( ! scriptItems.isEmpty()) {
                    portion = scriptItems.removeFirst();
					if( ! _scripts.isEmpty()) {
						Element script = (Element)_scripts.removeFirst();
						document.setScript( script);
					}
					else
						XRendererSupport.getContext().getLogger().warning(this, "No script context.");
                }
                else {
				  XRendererSupport.getContext().getLogger().error(this, "This should not happen");
				  portion = null;
				}
		        notifyAll();
            } // synch
            if( portion != null) {
                if( DEBUG_EXCUTION)
	                XRendererSupport.getContext().getLogger().message( this, portion);

                try {
                    exec( portion);
                } catch( Exception e) { // Stupid Rhino throws MISC exception!
				    onErrorWindowHandle(e);
                    XRendererSupport.getContext().getLogger().error( this, "JavaScript error:");
                    XRendererSupport.getContext().getLogger().error( this, portion);
                    XRendererSupport.getContext().getLogger().error( this, e);
                }
            }
        } // while()

        cleanup();
        if( DEBUG_THREAD)
        	XRendererSupport.getContext().getLogger().message( this, "JS Thread ended");
    } // run()

    public void setCurrentLine( int line) {
		currentLine = line;
    }

	protected void onErrorWindowHandle( Exception e) {
	    /** @todo Try to run window.onerror, if was set. */
	}

    protected void exec( Object portion) {
        try {
            if( portion instanceof String) {
                String js = (String)portion;
                ctx.evaluateString( window, js, "<file>", currentLine, null);
            } else
            if( portion instanceof URL) {
                URL js_src = (URL)portion;

                InputStream is = js_src.openStream();
                Reader js_reader = new InputStreamReader( is);
                ctx.evaluateReader( window, js_reader, "<file>", currentLine, null);
            }
        } catch( JavaScriptException jex) {
          if( IGNORE_JS_EXC) {
              XRendererSupport.getContext().getLogger().message( this, "Problem in JS -- ignored.");
          } else {
              XRendererSupport.getContext().getLogger().message( this, portion);
              XRendererSupport.getContext().getLogger().message( this, jex);
          }
        } catch( IOException iox) {
        	XRendererSupport.getContext().getLogger().message( this, "Exec error: " + iox + ": " + portion);
        }
    }

// Attributes:
    final static boolean DEBUG_THREAD = false;
    final static boolean DEBUG_EXCUTION = false;
    final static boolean IGNORE_JS_EXC = false;
	final static boolean JS_SYNCHRONIZE = false;

    private LinkedList scriptItems;
	private LinkedList /*<Element>*/ _scripts;

    private XJSDocument document;
    private XJSWindow window;
    private URL base;
    private Context ctx;
    private int currentLine = 0;
}