New Version of ExpressionOasis-3-0-1 Released

This is a micro release with few but important bugs fixes. The new 3.0.1 version should be used to have bug free solution. Fixed issues are:

GoogleCode: #1, #2, #3, #4

New Version of ExpressionOasis-3-0 Released

We are happy to announce release of new version of ExpressionOasis.

Version No: 3.0
Changes and new features with this new release are:
  • License changed from GPL to LGPLv3, so that more people can be benefited by using this free software
  • Major change in root packages name
    • package name is changed from org.ganges.expressionengine to org.vedantatree.expressionoasis
  • Introduced Maven build system, earlier it was based on Ant
  • Dynamic function support
    • Now custom functions can be defined in xml file, customfunctions.xml. System will pick these functions at runtime and make these available
  • Merged configurations in single config.xml file to some extent
  • In memory cache for Compiled Expressions
    • In memory cache may be useful for performance reasons. It can be turned on/off from config by setting value of 'cacheCompiledExpressions' element
  • Issue #2, #3 are fixed listed at Google Code
  • New test cases have been added
It can be downloaded from:

    XpressionEngine Project Renamed as ExpressionOasis

    Dear Friends,

    This project was earlier known as Xpressionengine ( However due to an existing trademark, project has been renamed to 'ExpressionOasis' now.

    We apologize for inconvenience caused.

    New version of ExpressionOasis Released - 2.3

    1. Support for ternary operator
    2. Support for XML expressions, using Xalan XPath
      1. XML Expressions are returning only String type value. 
      2. We can change it to some specific type like Number, String etc in future depending upon data or we should provide some type casting function
    3. Added more test cases 

    Download: Please go to Download page.

    New version of ExpressionOasis Released - 2.2

    New version of 'XpressionEngine' has been released at 

    Release notes: 
    • Support for more math functions
    • Bitwise operators
    • Change precendence of operators -
    • Change '=' operator with '=='

    New version of ExpressionOasis Released - 2.1

    Please refer to for more blogs. 

    New version of Expression Engine has been released at Google Code. It has the fix for unary operators and now supports expressions like

    false || ! false
    -3 * -2 / -6
    20 - (10/-2 + (-5 * -2)) / (15 * (-5/5) )

    Latest release is xpressionengine 2.1.

    ExpressionOasis released - Project for Expression Evaluation

    Please refer to for more blogs. 

    Expression Engine:

    What it will do -

    This system is defined to evaluate various kind of expressions.

    With the basic version, it is capable of evaluating the mathematical, logical and object property expressions. However system can be extended easily to evaluate any new type of expression like XML. The extensibility comes from the definition of grammar, parsing rules and expression implementations in the configuration files (XML based), which can be extended easily.

    System does have support for evaluating the functions and variables. User just need to provide the helping classes having implementation for functions and variables. Any new implementation can be plugged easily to the system.

    System is also capable to return the possible return type for any expression without actually evaluating the expression. Another capability is to get the possible operand types for any expression. This is very usable features while implementing the UI for any tool which is based on expression evaluation for its features.

    System is capable to work in multi-threaded environment.

    What purpose it will solve -

    The expression engine can be used as a plug-gable component with other framework components like
    -With BPEL based Workflow Engine which require an expression evaluator,
    -Or with a UI framework to evaluate the properties of various data objects and fill these in UI components,
    -Or by any scientific or mathematics research program,
    -Or with any financial or general software which need to evaluate the expressions.

    What problem will it solve -

    As define with the purpose, many of the software may need this component. It helps the developer to avoid reinventing the wheel and help them to easily plug the expression evaluation with their software. Besides it, it will be very simple in use and will not be dependent on other libraries (It may require one or two utility classes from our utility library).


    Airthmatic Expressions -


    Logical Expressions -

    a && b
    (2-1) > 0

    Expressions with variables -

    principle * rate * 100 / time, where principle, rate and time are the variables

    Expressions with Functions -

    CurrentBalance + SimpleInterest (principle, rate, time)

    Object property expression -, where person is the identifier which points to java object of Person class and city is the property of person and further name is the property of city

    Future Goals:
    XML Expression Support
    A Sample UI with support of expressions