JRuby JSR223接口忽略binidngs

Question

JRuby (1.6.7.2)框架的JSR223 javax.script接口似乎忽略了ScriptContext绑定中的绑定Java值。我做错了吗？下面是一个不起作用的简单示例：

private void run() throws ScriptException {
    ScriptEngine engine = new JRubyEngineFactory().getScriptEngine();
    LittleClass l = new LittleClass();
    engine.put("l", l);
    engine.eval("l.x;");
}

public class LittleClass {
    public int x;
    public void add() {
        x = x + 1;
    }
}

或者这是一个已知的问题？

Answer 1

默认情况下，局部变量不会在多次求值中存活。请参阅：http://kenai.com/projects/jruby/pages/RedBridge

要更改此行为，请设置org.jruby.embed.localvariable.behavior属性：

    System.setProperty("org.jruby.embed.localvariable.behavior", "persistent");

    ScriptEngine engine = new JRubyEngineFactory().getScriptEngine();
    LittleClass l = new LittleClass();
    engine.put("l", l);
    engine.eval("l.add");
    System.out.println(engine.eval("l.x"));