transformerimpl.java

java1.6众多例子参考

                    Vector uriAndLocalNames = null;
		    while (e.hasMoreTokens()) {
			final String token = e.nextToken();

                        // look for the last colon, as the String may be
                        // something like "http://abc.com:local"
                        int lastcolon = token.lastIndexOf(':');
                        String uri;
                        String localName;
                        if (lastcolon > 0) {
                            uri = token.substring(0, lastcolon);
                            localName = token.substring(lastcolon+1);
                        } else {
                            // no colon at all, lets hope this is the
                            // local name itself then
                            uri = null;
                            localName = token;
                        }

                        if (uriAndLocalNames == null) {
                            uriAndLocalNames = new Vector();
                        }
                        // add the uri/localName as a pair, in that order
                        uriAndLocalNames.addElement(uri);
                        uriAndLocalNames.addElement(localName);
                    }
                    handler.setCdataSectionElements(uriAndLocalNames);
		}
	    }
	}

	// Call setDoctype() if needed
	if (doctypePublic != null || doctypeSystem != null) {
	    handler.setDoctype(doctypeSystem, doctypePublic);
	}
    }

    /**
     * Internal method to create the initial set of properties. There
     * are two layers of properties: the default layer and the base layer.
     * The latter contains properties defined in the stylesheet or by
     * the user using this API.
     */
    private Properties createOutputProperties(Properties outputProperties) {
	final Properties defaults = new Properties();
	setDefaults(defaults, "xml");

	// Copy propeties set in stylesheet to base
	final Properties base = new Properties(defaults);
	if (outputProperties != null) {
	    final Enumeration names = outputProperties.propertyNames();
	    while (names.hasMoreElements()) {
		final String name = (String) names.nextElement();
		base.setProperty(name, outputProperties.getProperty(name));
	    }
	}
	else {
	    base.setProperty(OutputKeys.ENCODING, _translet._encoding);
	    if (_translet._method != null)
	        base.setProperty(OutputKeys.METHOD, _translet._method);
	}

	// Update defaults based on output method
	final String method = base.getProperty(OutputKeys.METHOD);
	if (method != null) {
	    if (method.equals("html")) {
	        setDefaults(defaults,"html");
	    }
	    else if (method.equals("text")) {
	        setDefaults(defaults,"text");
	    }
	}

	return base; 
    }

	/**
	 * Internal method to get the default properties from the
	 * serializer factory and set them on the property object.
	 * @param props a java.util.Property object on which the properties are set.
	 * @param method The output method type, one of "xml", "text", "html" ...
	 */
	private void setDefaults(Properties props, String method)
	{
		final Properties method_props =
			OutputPropertiesFactory.getDefaultMethodProperties(method);
		{
			final Enumeration names = method_props.propertyNames();
			while (names.hasMoreElements())
			{
				final String name = (String)names.nextElement();
				props.setProperty(name, method_props.getProperty(name));
			}
		}
	}
    /**
     * Verifies if a given output property name is a property defined in
     * the JAXP 1.1 / TrAX spec
     */
    private boolean validOutputProperty(String name) {
	return (name.equals(OutputKeys.ENCODING) ||
		name.equals(OutputKeys.METHOD) ||
		name.equals(OutputKeys.INDENT) ||
		name.equals(OutputKeys.DOCTYPE_PUBLIC) ||
		name.equals(OutputKeys.DOCTYPE_SYSTEM) ||
		name.equals(OutputKeys.CDATA_SECTION_ELEMENTS) ||
		name.equals(OutputKeys.MEDIA_TYPE) ||
		name.equals(OutputKeys.OMIT_XML_DECLARATION)   ||
		name.equals(OutputKeys.STANDALONE) ||
		name.equals(OutputKeys.VERSION) ||
		name.charAt(0) == '{');
    }

    /**
     * Checks if a given output property is default (2nd layer only)
     */
    private boolean isDefaultProperty(String name, Properties properties) {
	return (properties.get(name) == null);
    }

    /**
     * Implements JAXP's Transformer.setParameter()
     * Add a parameter for the transformation. The parameter is simply passed
     * on to the translet - no validation is performed - so any unused
     * parameters are quitely ignored by the translet.
     *
     * @param name The name of the parameter
     * @param value The value to assign to the parameter
     */
    public void setParameter(String name, Object value) {
        
        if (value == null) {
            ErrorMsg err = new ErrorMsg(ErrorMsg.JAXP_INVALID_SET_PARAM_VALUE, name);
            throw new IllegalArgumentException(err.toString());
        }
             
	if (_isIdentity) {
	    if (_parameters == null) {
		_parameters = new Hashtable();
	    }
	    _parameters.put(name, value);
	}
	else {
	    _translet.addParameter(name, value);
	}
    }

    /**
     * Implements JAXP's Transformer.clearParameters()
     * Clear all parameters set with setParameter. Clears the translet's
     * parameter stack.
     */
    public void clearParameters() {  
	if (_isIdentity && _parameters != null) {
	    _parameters.clear();
	}
	else {
	    _translet.clearParameters();
	}
    }

    /**
     * Implements JAXP's Transformer.getParameter()
     * Returns the value of a given parameter. Note that the translet will not
     * keep values for parameters that were not defined in the stylesheet.
     *
     * @param name The name of the parameter
     * @return An object that contains the value assigned to the parameter
     */
    public final Object getParameter(String name) {
	if (_isIdentity) {
	    return (_parameters != null) ? _parameters.get(name) : null;
	}
	else {
	    return _translet.getParameter(name);
	}
    }

    /**
     * Implements JAXP's Transformer.getURIResolver()
     * Set the object currently used to resolve URIs used in document().
     *
     * @return  The URLResolver object currently in use
     */
    public URIResolver getURIResolver() {
	return _uriResolver;
    }

    /**
     * Implements JAXP's Transformer.setURIResolver()
     * Set an object that will be used to resolve URIs used in document().
     *
     * @param resolver The URIResolver to use in document()
     */
    public void setURIResolver(URIResolver resolver) { 
	_uriResolver = resolver;
    }

    /**
     * This class should only be used as a DOMCache for the translet if the
     * URIResolver has been set.
     *
     * The method implements XSLTC's DOMCache interface, which is used to
     * plug in an external document loader into a translet. This method acts
     * as an adapter between TrAX's URIResolver interface and XSLTC's
     * DOMCache interface. This approach is simple, but removes the
     * possibility of using external document caches with XSLTC.
     *
     * @param baseURI The base URI used by the document call.
     * @param href The href argument passed to the document function.
     * @param translet A reference to the translet requesting the document
     */
    public DOM retrieveDocument(String baseURI, String href, Translet translet) {
	try {        
            // Argument to document function was: document('');
            if (href.length() == 0) {
                href = new String(baseURI);
            }    

            /*
             *  Fix for bug 24188
             *  Incase the _uriResolver.resolve(href,base) is null
             *  try to still  retrieve the document before returning null 
             *  and throwing the FileNotFoundException in
             *  com.sun.org.apache.xalan.internal.xsltc.dom.LoadDocument
             *
             */
            Source resolvedSource = _uriResolver.resolve(href, baseURI);
            if (resolvedSource == null)  {
                StreamSource streamSource = new StreamSource(
                     SystemIDResolver.getAbsoluteURI(href, baseURI));
                return getDOM(streamSource) ;
            } 

            return getDOM(resolvedSource);
	}
	catch (TransformerException e) {
	    if (_errorListener != null)
		postErrorToListener("File not found: " + e.getMessage());
	    return(null);
	}
    }

    /**
     * Receive notification of a recoverable error. 
     * The transformer must continue to provide normal parsing events after
     * invoking this method. It should still be possible for the application
     * to process the document through to the end.
     *
     * @param e The warning information encapsulated in a transformer 
     * exception.
     * @throws TransformerException if the application chooses to discontinue
     * the transformation (always does in our case).
     */
    public void error(TransformerException e)
	throws TransformerException 
    {
        Throwable wrapped = e.getException();
        if (wrapped != null) {
            System.err.println(new ErrorMsg(ErrorMsg.ERROR_PLUS_WRAPPED_MSG,
                                            e.getMessageAndLocation(),
                                            wrapped.getMessage()));
        } else {
            System.err.println(new ErrorMsg(ErrorMsg.ERROR_MSG,
                                            e.getMessageAndLocation()));
        }
        throw e;
    }

    /**
     * Receive notification of a non-recoverable error. 
     * The application must assume that the transformation cannot continue
     * after the Transformer has invoked this method, and should continue
     * (if at all) only to collect addition error messages. In fact,
     * Transformers are free to stop reporting events once this method has
     * been invoked.
     *
     * @param e The warning information encapsulated in a transformer
     * exception.
     * @throws TransformerException if the application chooses to discontinue
     * the transformation (always does in our case).
     */
    public void fatalError(TransformerException e)
	throws TransformerException 
    {
        Throwable wrapped = e.getException();
        if (wrapped != null) {
            System.err.println(new ErrorMsg(ErrorMsg.FATAL_ERR_PLUS_WRAPPED_MSG,
                                            e.getMessageAndLocation(),
                                            wrapped.getMessage()));
        } else {
            System.err.println(new ErrorMsg(ErrorMsg.FATAL_ERR_MSG,
                                            e.getMessageAndLocation()));
        }
        throw e;
    }

    /**
     * Receive notification of a warning.
     * Transformers can use this method to report conditions that are not
     * errors or fatal errors. The default behaviour is to take no action.
     * After invoking this method, the Transformer must continue with the
     * transformation. It should still be possible for the application to
     * process the document through to the end.
     *
     * @param e The warning information encapsulated in a transformer
     * exception.
     * @throws TransformerException if the application chooses to discontinue
     * the transformation (never does in our case).
     */
    public void warning(TransformerException e)
	throws TransformerException 
    {
        Throwable wrapped = e.getException();
        if (wrapped != null) {
            System.err.println(new ErrorMsg(ErrorMsg.WARNING_PLUS_WRAPPED_MSG,
                                            e.getMessageAndLocation(),
                                            wrapped.getMessage()));
        } else {
            System.err.println(new ErrorMsg(ErrorMsg.WARNING_MSG,
                                            e.getMessageAndLocation()));
        }
    }

    /**
     * This method resets  the Transformer to its original configuration
     * Transformer code is reset to the same state it was when it was
     * created
     * @since 1.5
     */
    public void reset() {

        _method = null;
        _encoding = null;
        _sourceSystemId = null;
        _errorListener = this;
        _uriResolver = null;
        _dom = null;
        _parameters = null;
        _indentNumber = 0;
        setOutputProperties (null);

    }
}