org.mozilla.javascript.WrapFactory Maven / Gradle / Ivy
/* -*- 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):
* Norris Boyd
* Igor Bukanov
*
* 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 ***** */
// API class
package org.mozilla.javascript;
/**
* Embeddings that wish to provide their own custom wrappings for Java
* objects may extend this class and call
* {@link Context#setWrapFactory(WrapFactory)}
* Once an instance of this class or an extension of this class is enabled
* for a given context (by calling setWrapFactory on that context), Rhino
* will call the methods of this class whenever it needs to wrap a value
* resulting from a call to a Java method or an access to a Java field.
*
* @see org.mozilla.javascript.Context#setWrapFactory(WrapFactory)
* @since 1.5 Release 4
*/
public class WrapFactory
{
/**
* Wrap the object.
*
* The value returned must be one of
*
* - java.lang.Boolean
* - java.lang.String
* - java.lang.Number
* - org.mozilla.javascript.Scriptable objects
* - The value returned by Context.getUndefinedValue()
* - null
*
* @param cx the current Context for this thread
* @param scope the scope of the executing script
* @param obj the object to be wrapped. Note it can be null.
* @param staticType type hint. If security restrictions prevent to wrap
object based on its class, staticType will be used instead.
* @return the wrapped value.
*/
public Object wrap(Context cx, Scriptable scope,
Object obj, Class staticType)
{
if (obj == null || obj == Undefined.instance
|| obj instanceof Scriptable)
{
return obj;
}
if (staticType != null && staticType.isPrimitive()) {
if (staticType == Void.TYPE)
return Undefined.instance;
if (staticType == Character.TYPE)
return new Integer(((Character) obj).charValue());
return obj;
}
if (!isJavaPrimitiveWrap()) {
if (obj instanceof String || obj instanceof Number
|| obj instanceof Boolean)
{
return obj;
} else if (obj instanceof Character) {
return String.valueOf(((Character)obj).charValue());
}
}
Class cls = obj.getClass();
if (cls.isArray()) {
return NativeJavaArray.wrap(scope, obj);
}
return wrapAsJavaObject(cx, scope, obj, staticType);
}
/**
* Wrap an object newly created by a constructor call.
* @param cx the current Context for this thread
* @param scope the scope of the executing script
* @param obj the object to be wrapped
* @return the wrapped value.
*/
public Scriptable wrapNewObject(Context cx, Scriptable scope, Object obj)
{
if (obj instanceof Scriptable) {
return (Scriptable)obj;
}
Class cls = obj.getClass();
if (cls.isArray()) {
return NativeJavaArray.wrap(scope, obj);
}
return wrapAsJavaObject(cx, scope, obj, null);
}
/**
* Wrap Java object as Scriptable instance to allow full access to its
* methods and fields from JavaScript.
*
* {@link #wrap(Context, Scriptable, Object, Class)} and
* {@link #wrapNewObject(Context, Scriptable, Object)} call this method
* when they can not convert javaObject to JavaScript primitive
* value or JavaScript array.
*
* Subclasses can override the method to provide custom wrappers
* for Java objects.
* @param cx the current Context for this thread
* @param scope the scope of the executing script
* @param javaObject the object to be wrapped
* @param staticType type hint. If security restrictions prevent to wrap
object based on its class, staticType will be used instead.
* @return the wrapped value which shall not be null
*/
public Scriptable wrapAsJavaObject(Context cx, Scriptable scope,
Object javaObject, Class staticType)
{
Scriptable wrap;
wrap = new NativeJavaObject(scope, javaObject, staticType);
return wrap;
}
/**
* Return false if result of Java method, which is instance of
* String, Number, Boolean and
* Character, should be used directly as JavaScript primitive
* type.
* By default the method returns true to indicate that instances of
* String, Number, Boolean and
* Character should be wrapped as any other Java object and
* scripts can access any Java method available in these objects.
* Use {@link #setJavaPrimitiveWrap(boolean)} to change this.
*/
public final boolean isJavaPrimitiveWrap()
{
return javaPrimitiveWrap;
}
/**
* @see #isJavaPrimitiveWrap()
*/
public final void setJavaPrimitiveWrap(boolean value)
{
Context cx = Context.getCurrentContext();
if (cx != null && cx.isSealed()) {
Context.onSealedMutation();
}
javaPrimitiveWrap = value;
}
private boolean javaPrimitiveWrap = true;
}