コンストラクタやメソッドで時計表示し何秒か時間を進めたり戻す

{
private int hour, minute, second;
public void setTime(int h, int m, int s)
{
if(h>=24)
h = 23;
if(h<0)
h = 0;
if(m>=60)
m = 59;
if(m<0)
m = 0;
if(s>=60)
s = 59;
if(s<0)
s = 0;

hour = h;
minute = m;
second = s;
}
public String getTime()
{
String h, m, s;

if(hour<10)
h = "0" + hour;
else
h = "" + hour;
if(minute<10)
m = "0" + minute;
else
m = "" + minute;
if(second<10)
s = "0" + second;
else
s = "" + second;
return h + ":" + m + ":" + s;
}
public void increaseOneSecond()
{

second++;
if(second >= 60){
second = 0;
minute++;
}

if(minute >= 60){
minute = 0;
hour++;
}
if(hour >= 24){
hour = 0;
}
}
public void decreaseOneSecond()
{
second--;

if(second < 0){
second = 59;
minute--;
}

if(minute < 0){
minute = 59;
hour--;
}
if(hour < 0){
hour = 23;
}
}
public void increaseSecond(int n)
{
for(int i=1; i<=n; i++){
increaseOneSecond();
}
}
public void decreaseSecond(int n)
{

for(int i=1; i<=n; i++){
decreaseOneSecond();
}
}
}

public class ren10_4
{
public static void main(String[] args) throws IOException
{
BufferedReader br =
new BufferedReader( new InputStreamReader( System.in ) );

MyTime t = new MyTime();
System.out.print("時を入力 > ");
int h = Integer.parseInt( br.readLine() );
System.out.print("分を入力 > ");
int m = Integer.parseInt( br.readLine() );
System.out.print("秒を入力 > ");
int s = Integer.parseInt( br.readLine() );
t.setTime(h, m, s);
System.out.println(t.getTime() + "に設定されました");
System.out.println();
System.out.print("進める(1)、戻す(2) 、終了(他の数)? > ");
int menu = Integer.parseInt( br.readLine() );
while( 1 <= menu && menu <= 2 ){
System.out.print("何秒? > ");
int seconds = Integer.parseInt( br.readLine() );
switch( menu ){

case 1:
if(seconds > 0){
t.increaseSecond(seconds);
}
else{
t.decreaseSecond(-seconds);
}
break;
case 2:
if(seconds > 0){
t.decreaseSecond(seconds);
}
else{
t.increaseSecond(-seconds);
}
break;

default:
break;
}
System.out.println(t.getTime() + "に設定されました");
System.out.println();
System.out.print("進める(1)、戻す(2) 、終了(他の数)? > ");
menu = Integer.parseInt( br.readLine() );
}
System.out.println("終了します");
}
}