[GROOVY-9802] groovy json - Unable to load FastStringService with java 11 http client

• Type: Bug
• Status: Open
• Priority: Major
• Resolution: Unresolved
• Affects Version/s: 3.0.6
• Component/s: JSON
• Environment: Groovy Version: 3.0.6 JVM: 11.0.9 Vendor: Amazon.com Inc. OS: Linux
• Assignee: Unassigned
• Reporter: Matias Bjarland
• Created: 30/Oct/20 13:26
• Updated: 08/Feb/23 20:42

Description

The following code: 

import groovy.json.*
import java.net.http.*
import static java.net.http.HttpResponse.*

def req = HttpRequest.newBuilder()
      .uri(URI.create('https://jsonplaceholder.typicode.com/todos/1'))
      .build()

def parser = new JsonSlurper()
// parser.parseText('{}') // <--- commenting in this line will make the code work

def res = HttpClient.newHttpClient().sendAsync(req, BodyHandlers.ofString())
       .thenApply(r -> r.body())
       .thenApply(parser::parseText)
       .join()

println "response: $res"

when run, will break with the following exception: 

─➤ groovy queryjson.groovy                                                                                           
Caught: java.util.concurrent.CompletionException: java.lang.RuntimeException: Unable to load FastStringService
java.util.concurrent.CompletionException: java.lang.RuntimeException: Unable to load FastStringService
Caused by: java.lang.RuntimeException: Unable to load FastStringService
  at org.apache.groovy.json.internal.FastStringUtils.getService(FastStringUtils.java:56)
  at org.apache.groovy.json.internal.FastStringUtils.toCharArray(FastStringUtils.java:66)
  at org.apache.groovy.json.internal.BaseJsonParser.parse(BaseJsonParser.java:113)
  at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
  at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
  at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
  at com.sun.proxy.$Proxy17.apply(Unknown Source)

commenting in the indicated line will make the code work. 

I assume this is caused by the fact that the `thenApply` block of code is run from a different (pooled) thread and from a different classloader context.

I get this, but in my mind having this simple example break is bad ergonomics and with the ubiquity of json APIs and the inclusion of a decent http client in java 11 I would expect this pattern to become quite common. I.e. wanting to create a no-deps groovy script / class which makes an http call and parses the returned json.