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Java Expression for Dynamic Invocation

JEDI is a fork of jakarta commons JEXL. The reasons of this modified version reside in a different approach in variable resolution of JexlContext, now JediContext.

JexlContext is nothing more than a map of (variable names, variable values), while JediContext hides the implementation details of variable names resolution.
However, this silght modification allows great flexibility in providing JediContext implementations.
See javadoc of org.omj.jedi.context for some example of the new resolution style.

The following example shows a basic usage of JEDI:

    // Create an expression object
    String exp = "foo.innerFoo.bar()";
    Expression e = ExpressionFactory.createExpression( exp );

    // Create a context and add data
    Map vars = new HashMap();
    vars.put("foo", new Foo() );
    JediContext jc = JediMapContext(vars);

    // Now evaluate the expression, getting the result
    Object o = e.evaluate(jc);

    // Create an expression object
    String exp = "foo.innerFoo.bar(System.currentTimeMillis())";
    Expression e = ExpressionFactory.createExpression( exp );
    
    // Create root context with common variables
    Map rootvars = new HashMap();
    rootvars.put("System", System.class);
    JediContext rootctx = JediMapContext(rootvars);
    

    // Create a new context for local variables
    Map vars = new HashMap();
    vars.put("foo", new Foo() );
    JediContext ctx = JediMapContext(vars);
    
    // Create resolution context for local variables that inherits from root context
    JediContext ctx = new JediDelegatingExtensibleContext(ctx, rootctx);

    // Now evaluate the expression, getting the result
    Object o = e.evaluate(jc);

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