Module jdk.jsobject

Class JSObject


  • public abstract class JSObject
    extends Object

    Allows Java code to manipulate JavaScript objects.

    When a JavaScript object is passed or returned to Java code, it is wrapped in an instance of JSObject. When a JSObject instance is passed to the JavaScript engine, it is unwrapped back to its original JavaScript object. The JSObject class provides a way to invoke JavaScript methods and examine JavaScript properties.

    Any data returned from the JavaScript engine to Java is converted to Java data types. Certain data passed to the JavaScript engine is converted to JavaScript data types.

    • Constructor Detail

      • JSObject

        protected JSObject()
        Constructs a new JSObject. Users should neither call this method nor subclass JSObject.
    • Method Detail

      • call

        public abstract Object call​(String methodName,
                                    Object... args)
                             throws JSException
        Calls a JavaScript method. Equivalent to "this.methodName(args[0], args[1], ...)" in JavaScript.
        Parameters:
        methodName - The name of the JavaScript method to be invoked.
        args - the Java objects passed as arguments to the method.
        Returns:
        Result of the method.
        Throws:
        JSException - when an error is reported from the browser or JavaScript engine.
      • eval

        public abstract Object eval​(String s)
                             throws JSException
        Evaluates a JavaScript expression. The expression is a string of JavaScript source code which will be evaluated in the context given by "this".
        Parameters:
        s - The JavaScript expression.
        Returns:
        Result of the JavaScript evaluation.
        Throws:
        JSException - when an error is reported from the browser or JavaScript engine.
      • getMember

        public abstract Object getMember​(String name)
                                  throws JSException
        Retrieves a named member of a JavaScript object. Equivalent to "this.name" in JavaScript.
        Parameters:
        name - The name of the JavaScript property to be accessed.
        Returns:
        The value of the propery.
        Throws:
        JSException - when an error is reported from the browser or JavaScript engine.
      • setMember

        public abstract void setMember​(String name,
                                       Object value)
                                throws JSException
        Sets a named member of a JavaScript object. Equivalent to "this.name = value" in JavaScript.
        Parameters:
        name - The name of the JavaScript property to be accessed.
        value - The value of the propery.
        Throws:
        JSException - when an error is reported from the browser or JavaScript engine.
      • removeMember

        public abstract void removeMember​(String name)
                                   throws JSException
        Removes a named member of a JavaScript object. Equivalent to "delete this.name" in JavaScript.
        Parameters:
        name - The name of the JavaScript property to be removed.
        Throws:
        JSException - when an error is reported from the browser or JavaScript engine.
      • getSlot

        public abstract Object getSlot​(int index)
                                throws JSException
        Retrieves an indexed member of a JavaScript object. Equivalent to "this[index]" in JavaScript.
        Parameters:
        index - The index of the array to be accessed.
        Returns:
        The value of the indexed member.
        Throws:
        JSException - when an error is reported from the browser or JavaScript engine.
      • setSlot

        public abstract void setSlot​(int index,
                                     Object value)
                              throws JSException
        Sets an indexed member of a JavaScript object. Equivalent to "this[index] = value" in JavaScript.
        Parameters:
        index - The index of the array to be accessed.
        value - The value to set
        Throws:
        JSException - when an error is reported from the browser or JavaScript engine.
      • getWindow

        @Deprecated(since="9")
        public static JSObject getWindow​(Applet applet)
                                  throws JSException
        Deprecated.
        The Applet API is deprecated. See the java.applet package documentation for further information.
        Returns a JSObject for the window containing the given applet. This method only works when the Java code is running in a browser as an applet. The object returned may be used to access the HTML DOM directly.
        Parameters:
        applet - The applet.
        Returns:
        JSObject representing the window containing the given applet or null if we are not connected to a browser.
        Throws:
        JSException - when an error is reported from the browser or JavaScript engine or if applet is null