As far as my understanding goes, method references can be used either statically or with wrapped object instance, for example:
public class MethodReferencesExampleTest {
class Example {
private String variable;
public Example(String variable) {
this.variable = variable;
}
public String getVariable() {
return variable;
}
}
@Test
public void shouldBeAbleToUseBothClassAndInstanceMethodReference() {
Example objectUnderTest = new Example("variable");
useClassMethodReference(Example::getVariable, objectUnderTest);
useInstanceMethodReference(objectUnderTest::getVariable);
}
private <T> void useClassMethodReference(Function<T, String> methodReference, T object) {
System.out.println("Class reference call result = " + methodReference.apply(object));
}
private void useInstanceMethodReference(Supplier<String> methodReference) {
System.out.println("Instance reference call result = " + methodReference.get());
}
}
What I would like to do is extract instance method reference and somehow convert it to class method reference, so that I could apply it to a different object of the same class, like:
private <T> void useInstanceMethodReferenceOnDifferentObjectThanItsSource(Supplier<String> instanceMethodReference, T object) {
Function<T, String> classMethodReference = /* some magical conversion */ instanceMethodReference;
System.out.println("Instance reference call result = " + classMethodReference.apply(object));
}
Is it at all possible? Byte-code wizardry like using cglib or even shady "hacks" are an acceptable answer.
