Question

如何从groovy获取执行的javascript代码的结果？我尝试了以下内容，但我总是回到字符串“世界”。我原本期望一个对象或地图。

import javax.script.ScriptEngineManager
import javax.script.SimpleBindings

def manager = new ScriptEngineManager()
manager.getEngineByName("JavaScript").eval("""
    {hello: name}
""", [name:'world'] as SimpleBindings)

Answer 1

容易！

您可以将对象映射到变量，然后返回...

import javax.script.*

def bindings = [name:'world']

def response = new ScriptEngineManager()
    .getEngineByName('javascript')
    .eval("var r = {hello:name}; r;", bindings as SimpleBindings)

println response.hello // -> world

或者您可以跟踪response地图对象，并更新...

import javax.script.*

def bindings = [name:'world',response:[:]]

new ScriptEngineManager()
    .getEngineByName('javascript')
    .eval("var r = {hello:name}; response.data = r;", bindings as SimpleBindings)

println bindings.response.data.hello // -> world

Groovy版本： 2.4.5

Java版本： 1.8.0_60

Answer 2

这有点棘手（我能找到的唯一解决方案是使用内部sun.com类）： - /

import javax.script.ScriptEngineManager
import javax.script.SimpleBindings
import sun.org.mozilla.javascript.internal.NativeObject

// A Category to parse NativeObject into a Map
class NativeObjectParser {
  static Map asMap( NativeObject jsobj ) {
    jsobj.allIds.inject( [:] ) { map, key ->
      def value = jsobj.get( key, jsobj )
      // Handle nested maps
      map << [ (key):value instanceof NativeObject ? value.asMap() : value ]
    }
  }
}

// Your code as you had it before (apart from the JS defines a var, and returns that var object)
def manager = new ScriptEngineManager()
def ret = manager.getEngineByName("JavaScript").eval("""
    var r = { 'hello': name }
    r
""", [ name:'world' ] as SimpleBindings )

// Do the unwrapping
def map = use( NativeObjectParser ) {
  ret.asMap()
}

println map

打印出来：

[hello:world]

感觉不是一种非常干净的做事方式（如果你有一个数组地图，可能需要一些工作）

但我能找到最好的： - /

如何从groovy执行Javascript代码并将结果作为地图获取？

2 个答案: