Rhino 1.6R1

E4X implementation
Other changes

Release Date: 2004-11-29

Rhino 1.6R1 is the new major release of Rhino. It supports ECMAScript for XML (E4X) as specified by ECMA 357 standard. E4X is a set of language extensions adding native XML support for JavaScript without affecting the existing code base. E4X example demonstrates various E4X constructions and their usage in JavaScript code.

This version of Rhino should be binary compatible with the current embeddings that use only public API unless the code use the previously deprected classes as documented below. Please report any incompatibility issues to Bugzilla.

E4X implementation

The E4X code was donated to the Rhino project by BEA and developed by staff from BEA and AgileDelta.

It uses XMLBeans library to implement E4X runtime. The implementation was tested against versions 1.0.2 and 1.0.3 of XMLBeans. Please make sure that xbean.jar is avaialble on the classpath if you use E4X in your scripts.

See Bugzilla 242805 for details. See also Bugzilla 270779 for the list of known issues with E4X implementation in Rhino 1.6R1.

Other changes

Common root for Rhino execeptions

Now all Rhino execption classes are derived from org.mozilla.javascript.RhinoException which extends java.lang.RuntimeException. The class gives the uniform way to access information about the script origin of the exception and simplifies execption handling in Rhino embeddings.

See Bugzilla 244492 for details.

Removal of code complexity limits in the interpreter

The interpreter mode in Rhino does not limit any longer the script size or code complexity. It should be possible to execute any script as long as JVM resources allow so.

See Bugzilla 244014 and Bugzilla 256339 for details.

Tail call elimination in the interpreter

The interpreter mode in Rhino implements tail call elimination to avoid excessive stack space consumption when a function returns result of a call to another function.

See Bugzilla 257128

Support for continuations in the interpreter

The interpreter mode in Rhino supports continuations. The code is based on the ideas from the original implementation of continuations by Christopher Oliver and SISC project. To use the continuations make sure that the interpreter mode is selected through setting the optimization level to -1 or by adding -opt -1 to the command line of Rhino shell.

Please note that the details of implementation and Java and JavaScript API for continuations may change in future in incompatible way.

See Bugzilla 258844

JavaImporter constructor

JavaImporter is a new global constructor that allows to omit explicit package names when scripting Java:

var SwingGui = JavaImporter(Packages.javax.swing,
                            Packages.javax.swing.event,
                            Packages.javax.swing.border,
                            java.awt.event,
                            java.awt.Point,
                            java.awt.Rectangle,
                            java.awt.Dimension);
...

with (SwingGui) {
    var mybutton = new JButton(test);
    var mypoint = new Point(10, 10);
    var myframe = new JFrame();
...
}

Previously such functionality was available only to embeddings that used org.mozilla.javascript.ImporterTopLevel class as the top level scope. The class provides additional importPackage() and importClass() global functions for scripts but their extensive usage has tendency to pollute the global name space with names of Java classes and prevents loaded classes from garbage collection.

See Bugzilla 245882 for details.

Context customization API

org.mozilla.javascript.ContextFactory provides new API for customization of org.mozilla.javascript.Context and ensures that application-specific Context subclasses will always be used when Rhino runtime needs to create Context instances. See Bugzilla 245882 for details.

Support for Date.now()

Date.now() function which is a SpiderMonkey extension to ECMAScript standard is available now in Rhino. The function returns number of milliseconds passed since 1970-01-01 00:00:00 UTC.

Removal of deprecated classes

The following classes that were deprecated in Rhino 1.5R5 are no longer available in Rhino 1.6R1:

org.mozilla.javascript.ClassNameHelper
org.mozilla.javascript.ClassRepository

See documentation for org.mozilla.javascript.optimizer.ClassCompiler that provides replacement for ClassNameHelper and ClassRepository.