做了个计时器，用了很多if嵌套，想请问下有没有更好的办法不用很多if的

private long mNext1;//计算下一秒
    private int second1 =0;//计时秒数个位
    private int second2 =0;//计时秒数十位
    private int minute1 =0;//计时分数个位
    private int minute2 =0;//计时分数十位

//计时
    private void drawTime(Canvas canvas){
        long current =System.currentTimeMillis();
        
        if(current>=mNext1){
            mNext1=current+1000;
            second1++;
            if(second1>9){
                second1-=10;//秒数的个位
            }
            if(second1==0){
                second2+=1;
                if(second2>5){
                    second2-=6;//秒数的十位
                    if(second2==0){
                        minute1+=1;
                        if(minute1>9){
                            minute1-=10;//分数的个位
                            if(minute1==0){
                                minute2+=1;//分数的十位
                            }
                        }
                    }
                }
            }        
        }   
        mPaint.setStrokeWidth(1);
        mPaint.setTextSize(30);
        mPaint.setColor(0xFFFFFF00);
        canvas.drawText((minute2+""+minute1+""+" : "+second2+""+second1+""), 370, 60, mPaint);//画出计时器   
        }