The javax.swing.JTable.set/getGridColor() javadoc states that default color is
"Color.gray". This is not true for Metal L&F, for example.

The statement about default color should be removed since it's look
and feel dependent.

Test example:

import java.awt.*;
import javax.swing.*;
import javax.swing.table.*;

public class jtable {
    public static void main (String [] args) {

        JTable t = new JTable();

        System.out.println(UIManager.getLookAndFeel());
        
        System.out.println(t.getGridColor());
        System.out.println(Color.gray);

    }
}

Test output under jdk1.4:

bash-2.00$ /usr/local/java/jdk1.4/solsparc/bin/java jtable
[The Java(tm) Look and Feel - javax.swing.plaf.metal.MetalLookAndFeel]
javax.swing.plaf.ColorUIResource[r=153,g=153,b=153]
java.awt.Color[r=128,g=128,b=128]