class Ideone {
  public static void main(String[] args) {
    final Test<String> testString = new Test<>();
    final String tString = testString.doSomethingWithT("Hello");
    System.out.println(tString);
    // will not compile since 1 is not a String:
    // int tInt = testString.doSomethingWithT(1);
    final String uString = testString.doSomethingWithU("World!");
    System.out.println(uString);
    final int uInt = testString.doSomethingWithU(1);
    System.out.println(uInt);
  }
}
 
class Test<T> {
  public T doSomethingWithT(T t) {
    return t;
  }
 
  public <U> U doSomethingWithU(U u) {
    return u;
  }
}

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