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Groovy,嵌入在Java中,回调Java

我知道我必须做一些事情,因为脑力死亡这个不能正常工作,但我处于一种情况,我想动态地将行为加载到正在运行的服务器中.我选择groovy作为我的工具来做到这一点.该行为需要引用服务器类路径上的类,例如我的模型对象以及Freemarker等第三方库.

我把这个愚蠢的POC聚集在一起,以显示可行性.我无法获得groovy脚本来解析Java类“ThingyDoodle”和“Fooable”,尽管事实上我将GroovyClasspath的父类路径设置为我当前的.

public class GroovyTest
{
    public static void main ( String [ ] argv ) throws Throwable
    {
            // Setting parent classloader!
            // also tried plain old "GroovyTest.class.getClassLoader()" as well
        GroovyClassLoader gcl = new GroovyClassLoader ( Thread.currentThread().getContextClassLoader() ) ;
        String src =
              "class Arf implements Fooable {
                 public String foo ( ) {
                   return new ThingyDoodle().doStuff('Arf');}}" ;
        Class clazz = gcl.parseClass(src, "AppleSauce.groovy");
        Object aScript = clazz.newInstance();
        Fooable myObject = (Fooable) aScript;
        System.out.println ( myObject.foo() ) ;
    }

    public static interface Fooable { public String foo ( ) ; }

    public static class ThingyDoodle
    {
        public String doStuff ( String input )
        {
            return "Hi Worlds" ;
        }
    }
}

我到底做错了什么?

Exception in thread "main" org.codehaus.groovy.control.MultipleCompilationErrorsException: startup Failed:
AppleSauce.groovy: 1: unable to resolve class Fooable
 @ line 1, column 1.
   class Arf implements Fooable { public String foo ( ) { return new ThingyDoodle().doStuff('Arf');}}
   ^

AppleSauce.groovy: 1: unable to resolve class ThingyDoodle
 @ line 1, column 63.
   ublic String foo ( ) { return new Thingy
                                     ^

解决方法:

您的代码中的问题是找不到Fooable接口和ThingyDoodle类,因为它们都是内部类,需要使用包含类名称进行限定,即GroovyTest.我在嵌入式脚本中限定了两个名称(并修复了脚本周围的引号),并按预期运行.

import groovy.lang.GroovyClassLoader;

public class GroovyTest
{

    public static void main ( String [ ] argv ) throws Throwable
    {
            // Setting parent classloader!
            // also tried plain old "GroovyTest.class.getClassLoader()" as well
        GroovyClassLoader gcl = new GroovyClassLoader ( Thread.currentThread().getContextClassLoader() ) ;
        String src =
              "class Arf implements GroovyTest.Fooable { " + 
                 "public String foo ( ) { " + 
                   "return new GroovyTest.ThingyDoodle().doStuff('Arf');}}" ;
        Class clazz = gcl.parseClass(src, "AppleSauce.groovy");
        Object aScript = clazz.newInstance();
        Fooable myObject = (Fooable) aScript;
        System.out.println ( myObject.foo() ) ;
    }       
     public static interface Fooable { public String foo ( ) ; }

    public static class ThingyDoodle
    {
        public String doStuff ( String input )
        {
            return "Hi Worlds" ;
        }
    }


}

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