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$Id$

                            Commons JEXL Package
                                Version 2.0
                               Release Notes


INTRODUCTION:
=============

JEXL is an Expression Language supporting most of the constructs in the
JSTL Expression Language, along with some additional extensions.

  http://commons.apache.org/jexl/

Changes in this version include:

Incompatible Changes
====================

Now requires Java 1.5 or later.

Version 2.0 resides in the org.apache.commons.jexl2 package; part of the version 1.x API is reimplemented as an
add-on source library in the jexl-compat directory; since it can not fully reimplement the original public 1.x, it may
only be used to ease transition in strictly controlled deployments.

The following classes are implemented through the jexl-compat source library:
  * ExpressionFactory
  * ScriptFactory
  * Expression
  * Script
  * JexlContext
  * JexlHelper

Migration notes
===============

When migrating from jexl 1.x to jexl 2.0, the following hints may be helpfull.

The following classes no longer exist:
  * ExpressionFactory, ScriptFactory: create a JexlEngine and use createExpression() or createScript()
  instead.

The following classes have been renamed and replaced:

  * VelMethod <=> JexlMethod
  * VelPropertyGet <=> JexlPropertyGet
  * VelPropertySet <=> JexlPropertySet

The following methods have been removed:

  * Info.getTemplateName() - use Info.getName() instead
  * Expression.addPostResolver() / Expression.addPreResolver() - set ant-like variables in JexlContext, implement
    a specific JexlContext or derive JexlcontextInterpreter/JexlEngine instead

Behavior changes
================

* Public fields are considered when using JexlPropertyGet / JexlPropertySet: Jexl 1.x behavior can be reimplemented
by subclassing UberspectImpl.

*Division (/ operator) behavior change: division between integers no longer casts its operands to double; integer division
    allways results in a integer. The 1.x behavior can be reimplemented by subclassing JexlArithmetic.

New Features:
=============

Assignment expression: a = b (and a.b.c = d)
   * Assigns a variable (ant-like variable or bean-property)

Ternary operator expression: a ? b : c  (and a ?: c)
   * The usual inline conditional shortcut and its 'Elvis' form (a ?: b evaluates as a ? a : b)

Constructor call expression: new('my.class.name', arguments...)
   * Creates a new instance of a class using the most appropriate constructor according
     to the actual arguments

Function namespace: ns:func(arguments...)
   * A function namespace allows the use of class or instance methods in function calls

UnifiedJEXL
   * Adds ${...} and #{...} JSP/EL syntax support on top of the JexlEngine

JSR-223 support
   * Implement JSR-223 Scripting Engine for JEXL script (need BSF-3.0 on Java < 6)

Error and exception handling
   * Configuring the leniency and verbosity of the Jexl engine allows user control over the
     error handling policy

Bugs fixed:
===========

* JEXL-90:	Jexl parser allows invalid expressions, e.g. "a=1 b=2 3"
* JEXL-88:	MethodKey.java - name clash getMostSpecific() with Java 1.5.0
* JEXL-87:	Inconsistent behaviour of arithmetical operations
* JEXL-81:	Introspector does not use ListGetExecutor for List
* JEXL-80:	Lenient mode should not throw exception when {g,s}etting an undefined property
* JEXL-78:	Ternary operator throws Exception when JexlEngine in strict mode
* JEXL-76:	Remove unnecessary class VisitorAdapter
* JEXL-71:	Parsing errors?
* JEXL-67:	Potential NPE in util.introspection.MethodKey
* JEXL-66:	testDottedNames expects map enumeration order
* JEXL-64:	Inconsistent behaviour of dotted names
* JEXL-62:	NPE in Interpreter
* JEXL-59:	ClassMap holds a reference to class
* JEXL-56:	Logging wrongly uses java.util.logging
* JEXL-50:	Div operator does not do integer division
* JEXL-49:	Block statements aren't parsed
* JEXL-48:	NPE during expression evaluation
* JEXL-45:	Unhandled division by zero
* JEXL-42:	NullPointerException evaluating an expression
* JEXL-40:	JEXL fails to find abstract public methods in the base class if overridden by non-public derived types
* JEXL-32:	BigDecimal values are treated as Long values which results in loss of precision
* JEXL-30:	ASTAddNode does not add BigDecimal objects correctly
* JEXL-27:	Cannot assign a value to the property of an object, such as object.prop = value.
* JEXL-26:	ASTArrayAccess messes up on fallback to JexlContext
* JEXL-19:	Ternary conditional not supported
* JEXL-3 :	Static method resolution and changes to context

Other issues fixed (Improvements/New Features):
===============================================

* JEXL-95:	Enhance JSR-223 implementation
* JEXL-94:	Allow stateful namespaces (ns:function)
* JEXL-93:	Add public fields as targets of set/get property
* JEXL-92:	JexlContext API should be more flexible
* JEXL-89:	Drop main() and suite() methods from Test cases
* JEXL-85:	2.0 grammar finishing touches & debugger update
* JEXL-82:	Change foreach syntax
* JEXL-77:	Rename last Velocity originated classes
* JEXL-72:	Remove deprecated classes and methods entirely
* JEXL-70:	Add main class to allow scripts etc to be tested
* JEXL-63:	JSR-223 support
* JEXL-61:	Usage of strong references on Method/Constructor & WeakHashMap usage
* JEXL-60:	Refactor o.a.c.jexl.util and o.a.c.jexl.util.introspection
* JEXL-58:	UnifiedJEXL
* JEXL-57:	Change pom.xml to make it Netbeans Maven2 plugin friendly
* JEXL-55:	JEXL 2.0 redux, attempting to restart the effort to release 2.0
* JEXL-54:	Light performance enhancements
* JEXL-47:	Allow single-line comments with //
* JEXL-43:	Website overview does not mention method calls and new 2.0 features
* JEXL-41:	Allow nested ${} evaluation
* JEXL-35:	Final API requirements
* JEXL-34:	Remove pre and post resolution of variables via the JexlExprResolver classes.
* JEXL-33:	Remove unnecessary throws Exception from various classes
* JEXL-29:	Support non-object-level functions/methods, as size and empty function
* JEXL-25:	Call method with varargs
* JEXL-24:	Support Long for integer literal instead of Integers
* JEXL-21:	operator overloading / hooks on operator processing
* JEXL-16:	allowing quote escaping
* JEXL-15:	Needs definable functions
* JEXL-11:	Don't make null convertible into anything
* JEXL-10:	Make possible checking for unresolved variables

Other Changes:
==============

o Add @since 2.0 tags to code so we can track API additions via Javadoc