Java: Need some advice on code reuse

Question

I have this big class I created, as part of a project I got for homework.
The class contains data members as well as some methods, and now I need to create another (almost) identical class.
it is almost identical, because the only difference is a constant number that appears here and there in the code.

for example, if the original class has:

for (int i=0; i<8; i++) {
    for (int j=0; j<8; j++) {
        labels[i][j]=new Label(panel, SWT.SHADOW_OUT);
        labels[i][j].setImage(empty);
    }
}

the new class should have:

for (int i=0; i<10; i++) {
    for (int j=0; j<10; j++) {
        labels[i][j]=new Label(panel, SWT.SHADOW_OUT);
        labels[i][j].setImage(empty);
    }
}

and if the original class has:

labels=new Label[8][8];

the new class should have:

labels=new Label[10][10];

meaning the only difference is 10 instead of 8, several times in the code.

In what way can I reuse the code here?
Does anyone have some idea?

Answer 1

Simply use class attributes:

public class MyClass {
    private final int labelsSize;
    private final Label[][] labels;
    public MyClass(final int labelsSize) { 
        this.labelsSize = labelsSize;
        this.labels = new Label[labelsSize][labelsSize];
    }
    // ...
    for (int i=0; i<labelsSize; i++) {
        for (int j=0; j<labelsSize; j++) {
            labels[i][j]=new Label(panel, SWT.SHADOW_OUT);
            labels[i][j].setImage(empty);
        } 
    }
}

Answer 2

You could pass in that number (either 8 or 10) as a parameter for this method, or as an argument for the constructor. Then set it as an instance variable and access it in this code.