Using Groovy MetaClass to overwrite Methods

Question

I have a POJO that uses a service to do something:

public class PlainOldJavaObject {

    private IService service;

    public String publicMethod(String x) {
          


        

Answer 1

Your syntax is a tiny bit off. The problem is that pojo is a Java Object and does not have a metaClass. To intercept calls to PlainOldJavaObject's doCallService using ExpandoMetaClass:

Just replace:

    pojo.metaClass.doCallService = { String s ->
        "no service"
    }

With:

    PlainOldJavaObject.metaClass.doCallService = { String s ->
        "no service"
    }