rythm dynamic expression evaluation

evalWithFel.java

    private Map<String, com.greenpineyu.fel.Expression> fels = new HashMap<String, Expression>();
    private FelEngine fel = new FelEngineImpl();
    
    private Expression getFel(String expr, Map<String, Object> context) {
        StringBuilder sb = new StringBuilder(expr);
        for (Object s : context.keySet()) {
            Object o = context.get(s);
            sb.append("|").append(s).append(":");
            if (null == o) sb.append("null");
            else sb.append(o.getClass());
        }
        String k = sb.toString();
        Expression e = fels.get(k);
        if (null == e) {
            FelEngine fel = new FelEngineImpl();
            FelContext ctx = fel.getContext();
            for (String s : context.keySet()) {
                ctx.set(s, context.get(s));
            }
            e = fel.compile(expr, ctx);
            fels.put(k, e);
        }
        return e;
    }
    
    public Object eval(String script, Map<String, Object> context) {
        //return MVEL.eval(script, context);
        FelEngine fel = new FelEngineImpl();
        FelContext ctx = fel.getContext();
        for (String s : context.keySet()) {
            ctx.set(s, context.get(s));
        }
        return getFel(script, context).eval(ctx);
    }

evalWithMVEL.java

   private Map<String, Serializable> mvels = new HashMap<String, Serializable>();

    public Object eval(String script, Map<String, Object> context) {
        Serializable  ce = mvels.get(script);
        if (null == ce) {
            ce = MVEL.compileExpression(script);
            mvels.put(script, ce);
        }
        return MVEL.executeExpression(ce, context);
    }