Below is a trace of the call writeStars2(3):
        writeStars2(3); (n > 0, recursive case)
            System.out.print("*");
            writeStars2(2); (n > 0, recursive case)
                System.out.print("*");
                writeStars2(1); (n > 0, recursive case)
                    System.out.print("*");
                    writeStars2(0); (n == 0, base case)
                        System.out.println();


Below is a trace of the call stutter(-348):
        stutter(-348)
            is < 0, so execute first branch
            compute stutter(-n), which is stutter(348)
            |   not < 0, not < 10, so execute third branch
            |   compute stutter(34)
            |   |   not < 0, not < 10, so execute third branch
            |   |   compute stutter(3)
            |   |   |   not < 0, but is < 10, so execute second branch
            |   |   |   return n * 11 (33)
            |   |   compute stutter(4)
            |   |   |   not < 0, but is < 10, so execute second branch
            |   |   |   return n * 11 (44)
            |   |   return first * 100 + second (33 * 100 + 44 = 3344)
            |   compute stutter(8)
            |   |   not < 0, but is < 10, so execute second branch
            |   |   return n * 11 (88)
            |   return first * 100 + second (3344 * 100 + 88 = 334488)
            return the negation of that result (-334488)