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java - Why can't I set an attribute to an object's array?

I want to set a[1] name to Gabriel for example, and it always give me the error:

Exception in thread "main" java.lang.NullPointerException 
at Register.main(Register.java:4)

My code is:

public class Register {
    public static void main(String[] args) {
        Employee a[] = new Employee[2];
        a[0].setName("Douglas");
    }
}

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When you create an array of non-primitive, you create an array of nulls of the specified size. Before accessing the objects' properties, you need to create them (using new):

Employee a[] = new Employee[2];
a[0] = new Employee(); // Here!
a[0].setName("Douglas");

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