nativestring.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) 1997-1999
 * the Initial Developer. All Rights Reserved.
 *
 * Contributor(s):
 *   Tom Beauvais
 *   Norris Boyd
 *   Mike McCabe
 *
 * 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;

import java.text.Collator;

/**
 * This class implements the String native object.
 *
 * See ECMA 15.5.
 *
 * String methods for dealing with regular expressions are
 * ported directly from C. Latest port is from version 1.40.12.19
 * in the JSFUN13_BRANCH.
 *
 * @author Mike McCabe
 * @author Norris Boyd
 */
final class NativeString extends IdScriptableObject
{
    static final long serialVersionUID = 920268368584188687L;

    private static final Object STRING_TAG = new Object();

    static void init(Scriptable scope, boolean sealed)
    {
        NativeString obj = new NativeString("");
        obj.exportAsJSClass(MAX_PROTOTYPE_ID, scope, sealed);
    }

    private NativeString(String s) {
        string = s;
    }

    public String getClassName() {
        return "String";
    }

    private static final int
        Id_length                    =  1,
        MAX_INSTANCE_ID              =  1;

    protected int getMaxInstanceId()
    {
        return MAX_INSTANCE_ID;
    }

    protected int findInstanceIdInfo(String s)
    {
        if (s.equals("length")) {
            return instanceIdInfo(DONTENUM | READONLY | PERMANENT, Id_length);
        }
        return super.findInstanceIdInfo(s);
    }

    protected String getInstanceIdName(int id)
    {
        if (id == Id_length) { return "length"; }
        return super.getInstanceIdName(id);
    }

    protected Object getInstanceIdValue(int id)
    {
        if (id == Id_length) {
            return ScriptRuntime.wrapInt(string.length());
        }
        return super.getInstanceIdValue(id);
    }

    protected void fillConstructorProperties(IdFunctionObject ctor)
    {
        addIdFunctionProperty(ctor, STRING_TAG, ConstructorId_fromCharCode,
                "fromCharCode", 1);
        addIdFunctionProperty(ctor, STRING_TAG,
                ConstructorId_charAt, "charAt", 2);
        addIdFunctionProperty(ctor, STRING_TAG,
                ConstructorId_charCodeAt, "charCodeAt", 2);
        addIdFunctionProperty(ctor, STRING_TAG,
                ConstructorId_indexOf, "indexOf", 2);
        addIdFunctionProperty(ctor, STRING_TAG,
                ConstructorId_lastIndexOf, "lastIndexOf", 2);
        addIdFunctionProperty(ctor, STRING_TAG,
                ConstructorId_split, "split", 3);
        addIdFunctionProperty(ctor, STRING_TAG,
                ConstructorId_substring, "substring", 3);
        addIdFunctionProperty(ctor, STRING_TAG,
                ConstructorId_toLowerCase, "toLowerCase", 1);
        addIdFunctionProperty(ctor, STRING_TAG,
                ConstructorId_toUpperCase, "toUpperCase", 1);
        addIdFunctionProperty(ctor, STRING_TAG,
                ConstructorId_substr, "substr", 3);
        addIdFunctionProperty(ctor, STRING_TAG,
                ConstructorId_concat, "concat", 2);
        addIdFunctionProperty(ctor, STRING_TAG,
                ConstructorId_slice, "slice", 3);
        addIdFunctionProperty(ctor, STRING_TAG,
                ConstructorId_equalsIgnoreCase, "equalsIgnoreCase", 2);
        addIdFunctionProperty(ctor, STRING_TAG,
                ConstructorId_match, "match", 2);
        addIdFunctionProperty(ctor, STRING_TAG,
                ConstructorId_search, "search", 2);
        addIdFunctionProperty(ctor, STRING_TAG,
                ConstructorId_replace, "replace", 2);
        addIdFunctionProperty(ctor, STRING_TAG,
                ConstructorId_localeCompare, "localeCompare", 2);
        addIdFunctionProperty(ctor, STRING_TAG,
                ConstructorId_toLocaleLowerCase, "toLocaleLowerCase", 1);
        addIdFunctionProperty(ctor, STRING_TAG,
                ConstructorId_fromCharCode, "fromCharCode", 1);
        super.fillConstructorProperties(ctor);
    }

    protected void initPrototypeId(int id)
    {
        String s;
        int arity;
        switch (id) {
          case Id_constructor:       arity=1; s="constructor";       break;
          case Id_toString:          arity=0; s="toString";          break;
          case Id_toSource:          arity=0; s="toSource";          break;
          case Id_valueOf:           arity=0; s="valueOf";           break;
          case Id_charAt:            arity=1; s="charAt";            break;
          case Id_charCodeAt:        arity=1; s="charCodeAt";        break;
          case Id_indexOf:           arity=1; s="indexOf";           break;
          case Id_lastIndexOf:       arity=1; s="lastIndexOf";       break;
          case Id_split:             arity=2; s="split";             break;
          case Id_substring:         arity=2; s="substring";         break;
          case Id_toLowerCase:       arity=0; s="toLowerCase";       break;
          case Id_toUpperCase:       arity=0; s="toUpperCase";       break;
          case Id_substr:            arity=2; s="substr";            break;
          case Id_concat:            arity=1; s="concat";            break;
          case Id_slice:             arity=2; s="slice";             break;
          case Id_bold:              arity=0; s="bold";              break;
          case Id_italics:           arity=0; s="italics";           break;
          case Id_fixed:             arity=0; s="fixed";             break;
          case Id_strike:            arity=0; s="strike";            break;
          case Id_small:             arity=0; s="small";             break;
          case Id_big:               arity=0; s="big";               break;
          case Id_blink:             arity=0; s="blink";             break;
          case Id_sup:               arity=0; s="sup";               break;
          case Id_sub:               arity=0; s="sub";               break;
          case Id_fontsize:          arity=0; s="fontsize";          break;
          case Id_fontcolor:         arity=0; s="fontcolor";         break;
          case Id_link:              arity=0; s="link";              break;
          case Id_anchor:            arity=0; s="anchor";            break;
          case Id_equals:            arity=1; s="equals";            break;
          case Id_equalsIgnoreCase:  arity=1; s="equalsIgnoreCase";  break;
          case Id_match:             arity=1; s="match";             break;
          case Id_search:            arity=1; s="search";            break;
          case Id_replace:           arity=1; s="replace";           break;
          case Id_localeCompare:     arity=1; s="localeCompare";     break;
          case Id_toLocaleLowerCase: arity=0; s="toLocaleLowerCase"; break;
          case Id_toLocaleUpperCase: arity=0; s="toLocaleUpperCase"; break;
          default: throw new IllegalArgumentException(String.valueOf(id));
        }
        initPrototypeMethod(STRING_TAG, id, s, arity);
    }

    public Object execIdCall(IdFunctionObject f, Context cx, Scriptable scope,
                             Scriptable thisObj, Object[] args)
    {
        if (!f.hasTag(STRING_TAG)) {
            return super.execIdCall(f, cx, scope, thisObj, args);
        }
        int id = f.methodId();
      again:
        for(;;) {
            switch (id) {
              case ConstructorId_charAt:
              case ConstructorId_charCodeAt:
              case ConstructorId_indexOf:
              case ConstructorId_lastIndexOf:
              case ConstructorId_split:
              case ConstructorId_substring:
              case ConstructorId_toLowerCase:
              case ConstructorId_toUpperCase:
              case ConstructorId_substr:
              case ConstructorId_concat:
              case ConstructorId_slice:
              case ConstructorId_equalsIgnoreCase:
              case ConstructorId_match:
              case ConstructorId_search:
              case ConstructorId_replace:
              case ConstructorId_localeCompare:
              case ConstructorId_toLocaleLowerCase: {
                thisObj = ScriptRuntime.toObject(scope,
                        ScriptRuntime.toString(args[0]));
                Object[] newArgs = new Object[args.length-1];
                for (int i=0; i < newArgs.length; i++)
                    newArgs[i] = args[i+1];
                args = newArgs;
                id = -id;
                continue again;
              }
    
              case ConstructorId_fromCharCode: {
                int N = args.length;
                if (N < 1)
                    return "";
                StringBuffer sb = new StringBuffer(N);
                for (int i = 0; i != N; ++i) {
                    sb.append(ScriptRuntime.toUint16(args[i]));
                }
                return sb.toString();
              }
    
              case Id_constructor: {
                String s = (args.length >= 1)
                    ? ScriptRuntime.toString(args[0]) : "";
                if (thisObj == null) {
                    // new String(val) creates a new String object.
                    return new NativeString(s);
                }
                // String(val) converts val to a string value.
                return s;
              }
    
              case Id_toString:
              case Id_valueOf:
                // ECMA 15.5.4.2: 'the toString function is not generic.
                return realThis(thisObj, f).string;
    
              case Id_toSource: {
                String s = realThis(thisObj, f).string;
                return "(new String(\""+ScriptRuntime.escapeString(s)+"\"))";
              }
    
              case Id_charAt:
              case Id_charCodeAt: {
                 // See ECMA 15.5.4.[4,5]
                String target = ScriptRuntime.toString(thisObj);
                double pos = ScriptRuntime.toInteger(args, 0);
                if (pos < 0 || pos >= target.length()) {
                    if (id == Id_charAt) return "";
                    else return ScriptRuntime.NaNobj;
                }
                char c = target.charAt((int)pos);
                if (id == Id_charAt) return String.valueOf(c);
                else return ScriptRuntime.wrapInt(c);
              }
    
              case Id_indexOf:
                return ScriptRuntime.wrapInt(js_indexOf(
                    ScriptRuntime.toString(thisObj), args));
    
              case Id_lastIndexOf:
                return ScriptRuntime.wrapInt(js_lastIndexOf(
                    ScriptRuntime.toString(thisObj), args));
    
              case Id_split:
                return js_split(cx, scope, ScriptRuntime.toString(thisObj),
                        args);
    
              case Id_substring:
                return js_substring(cx, ScriptRuntime.toString(thisObj), args);
    
              case Id_toLowerCase:
                // See ECMA 15.5.4.11
                return ScriptRuntime.toString(thisObj).toLowerCase();
    
              case Id_toUpperCase:
                // See ECMA 15.5.4.12
                return ScriptRuntime.toString(thisObj).toUpperCase();
    
              case Id_substr:
                return js_substr(ScriptRuntime.toString(thisObj), args);
    
              case Id_concat:
                return js_concat(ScriptRuntime.toString(thisObj), args);
    
              case Id_slice:
                return js_slice(ScriptRuntime.toString(thisObj), args);
    
              case Id_bold:
                return tagify(thisObj, "b", null, null);
    
              case Id_italics:
                return tagify(thisObj, "i", null, null);
    
              case Id_fixed:
                return tagify(thisObj, "tt", null, null);
    
              case Id_strike:
                return tagify(thisObj, "strike", null, null);
    
              case Id_small:
                return tagify(thisObj, "small", null, null);
    
              case Id_big:
                return tagify(thisObj, "big", null, null);