Java boolean addAll method and Generics type-parameter problems

I am currently learning the Generics and I got a task where I have to make an Array class with T type-parameter and an array data member and some methods (setItem, getItem, visitor, condition and addAll). I have problem with the addAll method:

public class Array<T> {
   private T[] array;

   public Array(T[] array){
      this.array = array;
   }

   public void setItem(int i, T item){
      if (i < 0 || i > array.length) {
        System.out.println("There is no this value in the array!");
      }
      array[i] = item;
   }

   public T getItem(int i){
       if (i < 0 || i > array.length) {    
          System.out.println("There is no this item in the array!"); 
       } 
       return array[i];  
   }

   public <E> boolean addAll(Collection<? extends E> c){
       boolean modified = false;
       for (E e : c){
           if (c.add(e)){
               modified = true;
           } 
       }
       return modified;
   }
}

The NB doesn’t accept the e in add method. I cannot figure out why…. If I use T type-parameter instead of E in the method (public boolean addAll(Collection<? extends T>c){} ) the situation is the same. I’ve got message that Incompatible types: E cannot be converted to CAP#1, where E is a type-variable, and CAP#1 is a fresh type-variable. What am I doing wrong?

My 2nd problem is with Array class used an abstract Condition class and it has 6 subclasses. The andCondition, orCondition and so on is OK, but the greaterCondition and doubleCondition do not work. I know where the problem is coming from, but I could not find a solution for that. First of all I used only <T> after classname and than try the following <T extends Number>, but no change:

public abstract class Condition<T> {
    public abstract boolean condition(T item);
}

public class doubleCondition<T extends Number> extends Condition<T> {

    public DoubleCondition (){   
    }

    @Override
    public boolean condition(T item) {
       if (item % 2 == 0){
           return true;
       }
       return false;
   }

I’ve got message: bad operand types for binary operator %, first type: T, second type: int, where T is a type-variable. What should I do with type-parameters or with boolean condition method that I be able to check that the item in the parameters can be divide with 2 without left, so it is double/couple.

And the greaterCondition class:

public class greaterCondition<T extends Number> extends Condition<T> {
    private T border;

    public  (T border){
        this.border = border;
    }

    @Override
    public boolean condition(T item) {
        return item > border;
    }
}

Here NB does not handle the > operator.

Any bit of help is appreciated!