Call private method of a class from within a mixin

I have a class which I am Injecting code into which looks like this:

public class Example {
               public void MethodOne() {
                        doesStuff();
                        methodTwo();
               }
               private void MethodTwo(){...}

and I want to Inject code like this:

...
    @Inject(method="MethodOne"...) 
    public void InjectMethodOne(CallbackInfo info) {
         if(conditionMet) {
              doesStuffDifferently();
              MethodTwo(); //Can't access this since its private and I don't have the object to use it on
              info.cancel()
         } else return; //Resume the code normally
    }

The org.spongepowered.asm.mixin.Shadow annotation allows you to declare in your mixin fields and methods that exist in the target class.

You can use a dummy body or the abstract modifier:

@Shadow
private void MethodTwo() {};
@Shadow
protected abstract void MethodTwo();