org.mozilla.javascript.WrapFactory Maven / Gradle / Ivy
Show all versions of rhino Show documentation
/* -*- 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/. */
// API class
package org.mozilla.javascript;
import java.math.BigInteger;
import java.util.List;
import java.util.Map;
/**
* 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 Integer.valueOf(((Character) obj).charValue());
return obj;
}
if (!isJavaPrimitiveWrap()) {
if (obj instanceof String
|| obj instanceof Boolean
|| obj instanceof Integer
|| obj instanceof Short
|| obj instanceof Long
|| obj instanceof Float
|| obj instanceof Double
|| obj instanceof BigInteger) {
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) {
if (List.class.isAssignableFrom(javaObject.getClass())) {
return new NativeJavaList(scope, javaObject);
} else if (Map.class.isAssignableFrom(javaObject.getClass())) {
return new NativeJavaMap(scope, javaObject);
}
return new NativeJavaObject(scope, javaObject, staticType);
}
/**
* Wrap a Java class as Scriptable instance to allow access to its static members and fields and
* use as constructor from JavaScript.
*
*
Subclasses can override this method to provide custom wrappers for Java classes.
*
* @param cx the current Context for this thread
* @param scope the scope of the executing script
* @param javaClass the class to be wrapped
* @return the wrapped value which shall not be null
* @since 1.7R3
*/
public Scriptable wrapJavaClass(Context cx, Scriptable scope, Class javaClass) {
return new NativeJavaClass(scope, javaClass);
}
/**
* 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;
}