else if(OPERATION_UPDATE.equals(in.toUpperCase())
     ||OPERATION_UPDATE.substring(0, 1).equals(in.toUpperCase())
     ||OPERATION_UPDATE.equals(pervious)){
    pervious=OPERATION_UPDATE;
    if(1==step){
     System.out.println("请输入要修改的员工ID：");
    }else if(2==step){
     Integer id=null;
     try {
      id = Integer.valueOf(in);
      try {
       user = action.getById(id);
       if(user==null){
        System.out.println("查询员工信息失败");
        step=1;
       }else{
        System.out.println("请输入新的员工信息[姓名]：");
       }
      } catch (Exception e) {
       System.out.println("查询员工信息失败");
       step=1;
      }
     } catch (Exception e) {
      System.out.println("请输入正确的员工ID：");
      step=1;
     }
     
    }else if(3==step){
     System.out.println(in);
     if(-1!=Integer.valueOf(in)){
      user.setName(in);
     }   
     System.out.println("请输入新的员工信息[性别]：");
    }

这是view层一段代码，运行update方法时，当输入姓名为：姚雪娟时，提示

Exception in thread "main" java.lang.NumberFormatException: For input string: "姚雪娟"
 at java.lang.NumberFormatException.forInputString(NumberFormatException.java:48)
 at java.lang.Integer.parseInt(Integer.java:449)
 at java.lang.Integer.valueOf(Integer.java:554)
 at com.view.View.main(View.java:218)

这是怎么回事？