io.engineblock.scripting

Interface Evaluator<T>

Type Parameters:

T - The return type that is needed by the caller

All Known Implementing Classes:

NashornEvaluator

public interface Evaluator<T>

An evaluator is a scripting helper that knows what its return type will be at runtime. You can create an Evaluator from an environment and a desired return type, then reuse it. Primitive types that can be mapped from the script to the return type should, including

• Double -> Long
• Double -> Integer
• Double -> Float
• Long -> Integer

An evaluator is not threadsafe by default. If you need threadsafe evaluators with similar semantics, wrap it in a ThreadLocal.

Method Summary

Modifier and Type	Method and Description
T	eval() Evaluate the provided script, returning the value that it yields
NashornEvaluator<T>	put(String varName, Object var) Set the variable environment of the evaluator
NashornEvaluator<T>	script(String scriptText)

Method Detail

eval

T eval()

Evaluate the provided script, returning the value that it yields

Returns:

An object of type T

script

NashornEvaluator<T> script(String scriptText)

Parameters:

scriptText - Nashorn compatible script text

Returns:

this NahornEvaluator, for method chaining

put

NashornEvaluator<T> put(String varName,
                        Object var)

Set the variable environment of the evaluator

Parameters:

varName - the variable name to add to the environment

var - the object to bind to the varname

Returns:

this NashornEvaluator, for method chaining