xml.java

這是一個javascript 的 interpreter是了解 web browser的好材料

/* -*- Mode: java; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*-
 *
 * ***** BEGIN LICENSE BLOCK *****
 * Version: MPL 1.1/GPL 2.0
 *
 * The contents of this file are subject to the Mozilla Public License Version
 * 1.1 (the "License"); you may not use this file except in compliance with
 * the License. You may obtain a copy of the License at
 * http://www.mozilla.org/MPL/
 *
 * Software distributed under the License is distributed on an "AS IS" basis,
 * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
 * for the specific language governing rights and limitations under the
 * License.
 *
 * The Original Code is Rhino code, released
 * May 6, 1999.
 *
 * The Initial Developer of the Original Code is
 * Netscape Communications Corporation.
 * Portions created by the Initial Developer are Copyright (C) 1997-2000
 * the Initial Developer. All Rights Reserved.
 *
 * Contributor(s):
 *   Ethan Hugg
 *   Terry Lucas
 *   Milen Nankov
 *
 * Alternatively, the contents of this file may be used under the terms of
 * the GNU General Public License Version 2 or later (the "GPL"), in which
 * case the provisions of the GPL are applicable instead of those above. If
 * you wish to allow use of your version of this file only under the terms of
 * the GPL and not to allow others to use your version of this file under the
 * MPL, indicate your decision by deleting the provisions above and replacing
 * them with the notice and other provisions required by the GPL. If you do
 * not delete the provisions above, a recipient may use your version of this
 * file under either the MPL or the GPL.
 *
 * ***** END LICENSE BLOCK ***** */

package org.mozilla.javascript.xml.impl.xmlbeans;

import java.io.Serializable;
import java.util.*;

import org.mozilla.javascript.*;

import org.apache.xmlbeans.XmlCursor;
import org.apache.xmlbeans.XmlCursor.XmlBookmark;
import org.apache.xmlbeans.XmlCursor.TokenType;
import org.apache.xmlbeans.XmlException;
import org.apache.xmlbeans.XmlObject;
import org.apache.xmlbeans.XmlOptions;

class XML extends XMLObjectImpl
{
    static final long serialVersionUID = -630969919086449092L;

    final static class XScriptAnnotation extends XmlBookmark implements Serializable
    {
        private static final long serialVersionUID = 1L;
        
        javax.xml.namespace.QName _name;
        XML _xScriptXML;


        ////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
        //
        //  Constructurs
        //
        ////////////////////////////////////////////////////////////////////////////////////////////////////////////////////

        XScriptAnnotation (XmlCursor curs)
        {
            _name = curs.getName();
        }

    }

    /**
     *
     */
    final static class NamespaceDeclarations
    {
        private int             _prefixIdx;
        private StringBuffer    _namespaceDecls;
        private String          _defaultNSURI;


        NamespaceDeclarations (XmlCursor curs)
        {
            _prefixIdx = 0;
            _namespaceDecls = new StringBuffer();

            skipNonElements(curs);
            _defaultNSURI = curs.namespaceForPrefix("");

            if (isAnyDefaultNamespace())
            {
                addDecl("", _defaultNSURI);
            }
        }


        private void addDecl (String prefix, String ns)
        {
            _namespaceDecls.append((prefix.length() > 0 ?
                                        "declare namespace " + prefix :
                                        "default element namespace") +
                                    " = \"" + ns + "\"" + "\n");
        }


        String getNextPrefix (String ns)
        {
            String prefix = "NS" + _prefixIdx++;

            _namespaceDecls.append("declare namespace " + prefix + " = " + "\"" + ns + "\"" + "\n");

            return prefix;
        }


        boolean isAnyDefaultNamespace ()
        {
            return _defaultNSURI != null ?_defaultNSURI.length() > 0 : false;
        }


        String getDeclarations()
        {
            return _namespaceDecls.toString();
        }
    }

    // Fields
    //static final XML prototype = new XML();
    private XScriptAnnotation _anno;

////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
    //
    //  Constructors
    //
    ////////////////////////////////////////////////////////////////////////////////////////////////////////////////////

    /**
     *
     * @param anno
     */
    private XML(XMLLibImpl lib, XScriptAnnotation anno)
    {
        super(lib, lib.xmlPrototype);
        _anno = anno;
        _anno._xScriptXML = this;
    }

    ////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
    //
    //  Public factories for creating a XScript XML object given an XBean cursor.
    //
    ////////////////////////////////////////////////////////////////////////////////////////////////////////////////////


    static XML createEmptyXML(XMLLibImpl lib)
    {
        XScriptAnnotation anno;

        XmlObject xo = XmlObject.Factory.newInstance();
        XmlCursor curs = xo.newCursor();
        try {
            anno = new XScriptAnnotation(curs);
            curs.setBookmark(anno);
        } finally {
            curs.dispose();
        }

        return new XML(lib, anno);
    }

    private static XML createXML (XMLLibImpl lib, XmlCursor curs)
    {
        if (curs.currentTokenType().isStartdoc())
        {
            curs.toFirstContentToken();
        }

        XScriptAnnotation anno = findAnnotation(curs);

        return new XML(lib, anno);
    }

    /**
     * Special constructor for making an attribute
     *
     */
    private static XML createAttributeXML(XMLLibImpl lib, XmlCursor cursor)
    {
        if (!cursor.isAttr())
            throw new IllegalArgumentException();

        XScriptAnnotation anno = new XScriptAnnotation(cursor);
        cursor.setBookmark(anno);

        return new XML(lib, anno);
    }


    /**
     *
     * @param qname
     * @param value
     * @return
     */
    static XML createTextElement(XMLLibImpl lib, javax.xml.namespace.QName qname, String value)
    {
        XScriptAnnotation anno;

        XmlObject xo = XmlObject.Factory.newInstance();
        XmlCursor cursor = xo.newCursor();
        try {
            cursor.toNextToken();

            cursor.beginElement(qname.getLocalPart(), qname.getNamespaceURI());
            //if(namespace.length() > 0)
            //    cursor.insertNamespace("", namespace);
            cursor.insertChars(value);

            cursor.toStartDoc();
            cursor.toNextToken();
            anno = new XScriptAnnotation(cursor);
            cursor.setBookmark(anno);
        } finally {
            cursor.dispose();
        }

        return new XML(lib, anno);
    }

    static XML createFromXmlObject(XMLLibImpl lib, XmlObject xo)
    {
        XScriptAnnotation anno;
        XmlCursor curs = xo.newCursor();
        if (curs.currentTokenType().isStartdoc())
        {
            curs.toFirstContentToken();
        }
        try {
            anno = new XScriptAnnotation(curs);
            curs.setBookmark(anno);
        } finally {
            curs.dispose();
        }
        return new XML(lib, anno);
    }

    static XML createFromJS(XMLLibImpl lib, Object inputObject)
    {
        XmlObject xo;
        boolean isText = false;
        String frag;

        if (inputObject == null || inputObject == Undefined.instance) {
            frag = "";
        } else if (inputObject instanceof XMLObjectImpl) {
            // todo: faster way for XMLObjects?
            frag = ((XMLObjectImpl) inputObject).toXMLString(0);
        } else {
            if (inputObject instanceof Wrapper) {
                Object wrapped = ((Wrapper)inputObject).unwrap();
                if (wrapped instanceof XmlObject) {
                    return createFromXmlObject(lib, (XmlObject)wrapped);
                }
            }
            frag = ScriptRuntime.toString(inputObject);
        }

        if (frag.trim().startsWith("<>"))
        {
            throw ScriptRuntime.typeError("Invalid use of XML object anonymous tags <></>.");
        }

        if (frag.indexOf("<") == -1)
        {
            // Must be solo text node, wrap in XML fragment
            isText = true;
            frag = "<textFragment>" + frag + "</textFragment>";
        }

        XmlOptions options = new XmlOptions();

        if (lib.ignoreComments)
        {
            options.put(XmlOptions.LOAD_STRIP_COMMENTS);
        }

        if (lib.ignoreProcessingInstructions)
        {
            options.put(XmlOptions.LOAD_STRIP_PROCINSTS);
        }

        if (lib.ignoreWhitespace)
        {
            options.put(XmlOptions.LOAD_STRIP_WHITESPACE);
        }

        try
        {
            xo = XmlObject.Factory.parse(frag, options);

            // Apply the default namespace
            Context cx = Context.getCurrentContext();
            String defaultURI = lib.getDefaultNamespaceURI(cx);

            if(defaultURI.length() > 0)
            {
                XmlCursor cursor = xo.newCursor();
                boolean isRoot = true;
                while(!cursor.toNextToken().isEnddoc())
                {
                    if(!cursor.isStart()) continue;

                    // Check if this element explicitly sets the
                    // default namespace
                    boolean defaultNSDeclared = false;
                    cursor.push();
                    while(cursor.toNextToken().isAnyAttr())
                    {
                        if(cursor.isNamespace())
                        {
                            if(cursor.getName().getLocalPart().length() == 0)
                            {
                                defaultNSDeclared = true;
                                break;
                            }
                        }
                    }
                    cursor.pop();
                    if(defaultNSDeclared)
                    {
                        cursor.toEndToken();
                        continue;
                    }

                    // Check if this element's name is in no namespace
                    javax.xml.namespace.QName qname = cursor.getName();
                    if(qname.getNamespaceURI().length() == 0)
                    {
                        // Change the namespace
                        qname = new javax.xml.namespace.QName(defaultURI,
                                                              qname.getLocalPart());
                        cursor.setName(qname);
                    }

                    if(isRoot)
                    {
                        // Declare the default namespace
                        cursor.push();
                        cursor.toNextToken();
                        cursor.insertNamespace("", defaultURI);
                        cursor.pop();

                        isRoot = false;
                    }
                }
                cursor.dispose();
            }
        }
        catch (XmlException xe)
        {
/*
todo need to handle namespace prefix not found in XML look for namespace type in the scope change.

            String errorMsg = "Use of undefined namespace prefix: ";
            String msg = xe.getError().getMessage();
            if (msg.startsWith(errorMsg))
            {
                String prefix = msg.substring(errorMsg.length());
            }
*/
            String errMsg = xe.getMessage();
            if (errMsg.equals("error: Unexpected end of file after null"))
            {
                // Create an empty document.
                xo = XmlObject.Factory.newInstance();
            }
            else
            {
                throw ScriptRuntime.typeError(xe.getMessage());
            }
        }
        catch (Throwable e)
        {
            // todo: TLL Catch specific exceptions during parse.
            throw ScriptRuntime.typeError("Not Parsable as XML");
        }

        XmlCursor curs = xo.newCursor();
        if (curs.currentTokenType().isStartdoc())
        {
            curs.toFirstContentToken();
        }

        if (isText)
        {
            // Move it to point to the text node
            curs.toFirstContentToken();
        }

        XScriptAnnotation anno;
        try
        {
            anno = new XScriptAnnotation(curs);
            curs.setBookmark(anno);
        }
        finally
        {
            curs.dispose();
        }

        return new XML(lib, anno);
    }

    static XML getFromAnnotation(XMLLibImpl lib, XScriptAnnotation anno)
    {
        if (anno._xScriptXML == null)
        {
            anno._xScriptXML = new XML(lib, anno);
        }

        return anno._xScriptXML;
    }

////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
    //
    //  Private functions:
    //
    ////////////////////////////////////////////////////////////////////////////////////////////////////////////////////

    /**
     *
     * @param curs
     * @return
     */
    private static TokenType skipNonElements (XmlCursor curs)
    {
        TokenType tt = curs.currentTokenType();
        while (tt.isComment() || tt.isProcinst())
        {
            tt = curs.toNextToken();
        }

        return tt;
    }

    /**
     *
     * @param curs
     * @return
     */
    protected static XScriptAnnotation findAnnotation(XmlCursor curs)
    {
        XmlBookmark anno = curs.getBookmark(XScriptAnnotation.class);
        if (anno == null)
        {
            anno = new XScriptAnnotation(curs);
            curs.setBookmark(anno);
        }

        return (XScriptAnnotation)anno;
    }

    /**
     *
     * @return
     */
    private XmlOptions getOptions()
    {
        XmlOptions options = new XmlOptions();

        if (lib.ignoreComments)
        {
            options.put(XmlOptions.LOAD_STRIP_COMMENTS);
        }

        if (lib.ignoreProcessingInstructions)
        {
            options.put(XmlOptions.LOAD_STRIP_PROCINSTS);
        }

        if (lib.ignoreWhitespace)
        {
            options.put(XmlOptions.LOAD_STRIP_WHITESPACE);
        }

        if (lib.prettyPrinting)
        {
            options.put(XmlOptions.SAVE_PRETTY_PRINT, null);
            options.put(XmlOptions.SAVE_PRETTY_PRINT_INDENT, new Integer(lib.prettyIndent));
        }

        return options;
    }


    /**
     *
     * @param cursor
     * @param opts
     * @return
     */
    private static String dumpNode(XmlCursor cursor, XmlOptions opts)
    {