Groovy从应用程序访问脚本变量

Question

在使用GroovyShell执行脚本之前，需要访问groovy脚本文件中定义的变量
但是，我收到错误：

groovy.lang.MissingPropertyException: No such property: _THREADS for class: Test1

//Test1.groovy
_THREADS=10;
println("Hello from the script test ")

//scriptRunner.groovy
File scriptFile = new File("Test1.groovy");
def sharedData = new Binding()
def shell = new GroovyShell(sharedData)
def script = shell.parse (scriptFile);
def thread = script.getProperty('_THREADS'); // getting ERROR --
// No such property: _THREADS for class: Test1
//-------
//now run the threads
script.run()

Answer 1

在获取属性/绑定之前必须运行脚本

def sharedData = new Binding()
def shell = new GroovyShell(sharedData)
def script = shell.parse (''' _THREADS=10 ''')
script.run()
println script.getProperty('_THREADS')

尝试在groovy控制台中为以下代码打开AST Browser (Ctrl+T)：

_THREADS=10

您将看到大约以下生成的类：

public class script1663101205410 extends groovy.lang.Script { 
public java.lang.Object run() {
_THREADS = 10
}
}

其中_THREADS = 10将属性分配给绑定

然而，可以将_THREADS定义为一个函数，这样就可以在不运行脚本的情况下访问它。

def sharedData = new Binding()
def shell = new GroovyShell(sharedData)
def script = shell.parse (''' def get_THREADS(){ 11 } ''')
println script.getProperty('_THREADS')

Answer 2

使用@Field获得解决方案，解析后可以访问修饰符值

import groovy.transform.Field
@Field _THREADS=10

File scriptFile = new File("Test1.groovy");
def sharedData = new Binding()
def shell = new GroovyShell(sharedData)
def script = shell.parse (scriptFile);
def thread = script.getProperty('_THREADS'); //value is accessible