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I am building an evaluator which underneath uses JEXL. I know how to introduce the workspaces in Jexl, but that only allows a class definition, I need to define a method definition. In the following example, for getting access to log function of Math, I have to add that into the function context. I want to be able to evaluate an expression: "log(5)" i.e. without using the qualifier.

Map<String, Object> funcs = new HashMap<String, Object>();
funcs.put("math", Math.class);

JexlEngine jexl = new JexlBuilder().namespaces(funcs).create();
JexlExpression je = jexl.createExpression("math:log(5)");
je.evaluate();
Gagan Maheshwari
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1 Answers1

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You can use the 'null' namespace if Math is the sole source of functions.

Map<String, Object> funcs = new HashMap<String, Object>();
funcs.put(null, Math.class);
JexlEngine jexl = new JexlBuilder().namespaces(funcs).create();
JexlExpression je = jexl.createExpression("log(5)");
Object result = je.evaluate(null);
Assert.assertNotNull(result);

If you need more than Math as a source, I'm afraid you'll have to create your own class that delegates each method to its sources.

henrib
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