Groovy - add a property or method dynamically to this metaClass

Question

I want to dynamically add field and methods to metaClassmy current object. I tried

this.metaClass.testProp = "test"

to add a field called testProp. However i get

groovy.lang.MissingPropertyException: No such property: testProp for class: groovy.lang.MetaClassImpl

When I do the same thing at the class level, for example. adding testProp to the class, not directly to the object

Process.metaClass.testProp = "test"

it works, but my object does NOT inherit the field. Any ideas or pointers in the right direction would be very helpful.

Answer 1

Short answer:

Process.metaClass.testProp = "test"
this.metaClass = null
assert this.testProp == "test"

Long answer:

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Process.metaClass.testProp = "test"
this.metaClass = null
assert this.testProp == "test"

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