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java - Array initialization gives null pointer exception

I am learning Java recently and was trying to work with classes.But I am not able to initialize array objects

 class Tablet
 {
    String S = null;
    void set(String a)
    {
        S = a;
    }
}

public class questions
{

public static void main(String args[])
{

    Tablet[] T = new Tablet[6];
    for(int i = 0;i<6;i++)
    {
        T[i].set("111"); // I get null pointer exception here
    }

    //solution(T,6);
} 
}

can anybody tell me where I am going wrong?

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by (71.8m points)

When you do

Tablet[] T = new Tablet[6];

You are creating array of references(i.e Array of reference variables) which are not pointing to anywhere else i.e they are null.You need to assign objects to above created reference variables in array.

Tablet[] T = new Tablet[6];
    for(int i = 0;i<6;i++)
    {
        T[i]=new Tablet();
        T[i].set("111"); // No Null Pointer Exception Now
    }

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