Adding JPanels with loops

Okay... not sure what I'm doing wrong but I'm trying to create an array of JPanels, and using a loop to add them to a main panel... It compiles fine, but theres a runtime error "nullPointerException" every time I try to run it and I'm not quite comprehending why...
JPanel[] Cell_Array = new JPanel[100];
JLabel[] Label_Array = new JLabel[100];
     for (int i=0;i<100;i++) {
          Cell_Array.setBackground(Color.black);
          Label_Array[i].setText(" ");
          Cell_Array[i].add(Label_Array[i]);
          Main_Panel.add(Cell_Array[i]);

You created the array but you have not put any panels into the array, so there is a null at every spot in the array.

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