org.mozilla.javascript.NativeScript Maven / Gradle / Ivy

Go to download
Show more of this group Show more artifacts with this name
Show all versions of rhino Show documentation
The Rhino JavaScript Engine for Java
The newest version!
/* -*- Mode: java; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*-
 *
 * This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

package org.mozilla.javascript;

/**
 * The JavaScript Script object.
 *
 * Note that the C version of the engine uses XDR as the format used
 * by freeze and thaw. Since this depends on the internal format of
 * structures in the C runtime, we cannot duplicate it.
 *
 * Since we cannot replace 'this' as a result of the compile method,
 * will forward requests to execute to the nonnull 'script' field.
 *
 * @since 1.3
 * @author Norris Boyd
 */

class NativeScript extends BaseFunction
{
    static final long serialVersionUID = -6795101161980121700L;

    private static final Object SCRIPT_TAG = "Script";

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

    private NativeScript(Script script)
    {
        this.script = script;
    }

    /**
     * Returns the name of this JavaScript class, "Script".
     */
    @Override
    public String getClassName()
    {
        return "Script";
    }

    @Override
    public Object call(Context cx, Scriptable scope, Scriptable thisObj,
                       Object[] args)
    {
        if (script != null) {
            return script.exec(cx, scope);
        }
        return Undefined.instance;
    }

    @Override
    public Scriptable construct(Context cx, Scriptable scope, Object[] args)
    {
        throw Context.reportRuntimeError0("msg.script.is.not.constructor");
    }

    @Override
    public int getLength()
    {
        return 0;
    }

    @Override
    public int getArity()
    {
        return 0;
    }

    @Override
    String decompile(int indent, int flags)
    {
        if (script instanceof NativeFunction) {
            return ((NativeFunction)script).decompile(indent, flags);
        }
        return super.decompile(indent, flags);
    }

    @Override
    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_exec:        arity=0; s="exec";        break;
          case Id_compile:     arity=1; s="compile";     break;
          default: throw new IllegalArgumentException(String.valueOf(id));
        }
        initPrototypeMethod(SCRIPT_TAG, id, s, arity);
    }

    @Override
    public Object execIdCall(IdFunctionObject f, Context cx, Scriptable scope,
                             Scriptable thisObj, Object[] args)
    {
        if (!f.hasTag(SCRIPT_TAG)) {
            return super.execIdCall(f, cx, scope, thisObj, args);
        }
        int id = f.methodId();
        switch (id) {
          case Id_constructor: {
            String source = (args.length == 0)
                            ? ""
                            : ScriptRuntime.toString(args[0]);
            Script script = compile(cx, source);
            NativeScript nscript = new NativeScript(script);
            ScriptRuntime.setObjectProtoAndParent(nscript, scope);
            return nscript;
          }

          case Id_toString: {
            NativeScript real = realThis(thisObj, f);
            Script realScript = real.script;
            if (realScript == null) { return ""; }
            return cx.decompileScript(realScript, 0);
          }

          case Id_exec: {
            throw Context.reportRuntimeError1(
                "msg.cant.call.indirect", "exec");
          }

          case Id_compile: {
            NativeScript real = realThis(thisObj, f);
            String source = ScriptRuntime.toString(args, 0);
            real.script = compile(cx, source);
            return real;
          }
        }
        throw new IllegalArgumentException(String.valueOf(id));
    }

    private static NativeScript realThis(Scriptable thisObj, IdFunctionObject f)
    {
        if (!(thisObj instanceof NativeScript))
            throw incompatibleCallError(f);
        return (NativeScript)thisObj;
    }

    private static Script compile(Context cx, String source)
    {
        int[] linep = { 0 };
        String filename = Context.getSourcePositionFromStack(linep);
        if (filename == null) {
            filename = "