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Types compatibility check

Suppose you have some class:

class Conf {
    SubConf<List<String>> sub; 
}

And some other class:

class Listener {
    listen(SubConf<List<Integer>> obj);
}

And you want to check if field value from Conf could be used in listener:

// for more complex cases there may be generics resolution too 
// pure reflection just for clarity
Type listenerArg = Listener.class
                        .getMethod("listen", SubConf.class)
                        .getGenericParameterTypes()[0];
Type confField = Conf.getField("sub").getGenericType();

// not assignable because of list generics: String vs Integer
TypeUtils.isAssignable(confField, listnerArg) == false    

Note

Possible name variables (not resolved) in types are replaced with Object.class (List<T> == List<Object>). Use context.resolveType(type) to replace type variables with known types before comparison (and use context.resolveTypeGenerics(type) to get direct generics of type).

Types may also be checked for compatibility:

Type one = List<Number> // ParameterizedType
Type two = List<Integer> // ParameterizedType

TypeUtils.isAssignable(one, two) == false
// means one assignable to two or two assignable to one
TypeUtils.isCompatible(one, two) == true
// detects type with more specific definition
TypeUtils.isMoreSpecific(one, two) == false
TypeUtils.getMoreSpecific(one, two) == two

If required, you can implement your own logic based on types comparison: see types walker section.