1. Create simple java class:

package test;

import java.util.Arrays;
import java.util.Comparator;

public class ClassA {

    public void m2() {
        int[][] pairs = new int[][]{{125, 24}, {658, 5}, {13, 10}};
        Arrays.sort(pairs, new Comparator<int[]>() {
            @Override
            public int compare(int[] a, int[] b) {
                return a[0] - b[0];
            }
        });
    }
}

2. Right click "Comparator" and from pop-up menu select Refactor > Convert Anonymous to Member...

3. Type new name "aaa" and press Enter

4. Press 4 times Undo for getting the original code like in step (1)

5. Press 4 times Redo for getting the code like in step (3)

>> Redo doesn't rename "ComparatorImpl" to "aaa"

Product Version: NetBeans IDE Dev (Build 201312110002)
Java: 1.7.0_45; Java HotSpot(TM) 64-Bit Server VM 24.45-b08
Runtime: Java(TM) SE Runtime Environment 1.7.0_45-b18
System: Windows 7 version 6.1 running on amd64; Cp1252; en_US (nb)