#!/usr/bin/env groovy
@Grapes([
    @Grab(group='org.jvnet.hudson', module='xstream', version='1.4.7-jenkins-1'),
])
def a

println 'xstream'
com.thoughtworks.xstream.XStream s = new com.thoughtworks.xstream.XStream()
println s
def reg1 = s.converterRegistry
println "using property: $reg1"

com.thoughtworks.xstream.XStream.metaClass.methodMissing = { String name, def args ->
    println "missing $name"
    if (name=="getConverterRegistry") {
        return delegate.converterRegistry
    }
}

def reg2 = s.getConverterRegistry()
println "using getter  : $reg2"

println "ok"

com.thoughtworks.xstream.XStream@6c45ee6e
using property: com.thoughtworks.xstream.XStream$2@2e8e8225
missing getConverterRegistry
using getter  : com.thoughtworks.xstream.XStream$2@2e8e8225
ok

#!/usr/bin/env groovy

import hudson.util.XStream2
import com.thoughtworks.xstream.XStream

@Grapes([
    @Grab(group='org.jvnet.hudson', module='xstream', version='1.4.7-jenkins-1'),
    @Grab(group='org.jenkins-ci.main', module='jenkins-core', version='1.642.3', transitive=false),
])
def a

XStream.metaClass.methodMissing = { String name, def args ->
    println "missing $name for XStream"
    if (name=="getConverterRegistry") {
        return delegate.converterRegistry
    }
}

def reg2 = new XStream().getConverterRegistry()
println reg2

XStream2.metaClass.methodMissing = { String name, def args ->
    println "missing $name for XStream2"
    if (name=="getConverterRegistry") {
        return delegate.converterRegistry
    }
}

println 'xstream2'
XStream2 s2 = new XStream2() // internal call to this.getConverterRegistry()
println "ok"

missing getConverterRegistry for XStream
com.thoughtworks.xstream.XStream$2@c2db68f
xstream2
Caught: java.lang.NoSuchMethodError: hudson.util.XStream2.getConverterRegistry()Lcom/thoughtworks/xstream/converters/ConverterRegistry;
java.lang.NoSuchMethodError: hudson.util.XStream2.getConverterRegistry()Lcom/thoughtworks/xstream/converters/ConverterRegistry;
        at hudson.util.XStream2.wrapMapper(XStream2.java:188)
        at com.thoughtworks.xstream.XStream.buildMapper(XStream.java:610)
        at com.thoughtworks.xstream.XStream.<init>(XStream.java:568)
        at com.thoughtworks.xstream.XStream.<init>(XStream.java:496)
        at com.thoughtworks.xstream.XStream.<init>(XStream.java:465)
        at com.thoughtworks.xstream.XStream.<init>(XStream.java:411)
        at com.thoughtworks.xstream.XStream.<init>(XStream.java:350)
        at hudson.util.XStream2.<init>(XStream2.java:89)
        at TestXStream2.run(TestXStream2.groovy:33)