Java generics question - Class<T> vs. T? -

i'm using hibernate validator , trying create little util class:

public class datarecordvalidator<t> {     public void validate(class<t> clazz, t validateme) {         classvalidator<t> validator = new classvalidator<t>(clazz);         invalidvalue[] errors = validator.getinvalidvalues(validateme);         [...]     } } 

question is, why need supply class<t> clazz parameter when executing new classvalidator<t>(clazz)? why can't specify:

1. t in classvalidator<t>(t)?
2. validateme.getclass() in classvalidator<t>(validateme.getclass())

i errors when try both options.

edit: understand why #1 doesn't work. don't why #2 doesn't work. error #2:

cannot find symbol symbol  : constructor classvalidator(java.lang.class<capture#279 of ? extends java.lang.object>) location: class org.hibernate.validator.classvalidator<t> 

note: hibernate api method (here)

if validate method yours, can safely skip class atribute.

public void validate(t validateme) {     classvalidator<t> validator =             new classvalidator<t>((class<t>) validateme.getclass());     ... } 

but classvalidator constructor requires class argument.

using unsafe cast not preferred, in case safe if don't have this:

class {..} class b extends {..}  new datarecordvalidator<a>.validate(new b()); 

if think need that, include class argument in method. otherwise may getting classcastexception @ runtime, debuggable, although it's not quite idea behind generics.