入力後にプログラムが印刷されないのはなぜですか？

Question

私はロックペーパーのハサミプログラムをJavaで作っていますし、すべてのコードを持っています。それは私に必要な出力を与えるはずですが、実行するたびに入力ステートメントだけを出力します。私はdo文の後に入力文がある行を印刷し、それを出力しますが、if文には何も印刷されません。理由は分かりません。これは私が持っているものです。助けていただきありがとうございます。要求コードを移動：デバッグを行い、より簡単にプログラムを読み込むために

public static void main(String[] args) 
{ 
    Scanner input = new Scanner(System.in); 
    Random rand = new Random(); 

    String replay = (""); 
    String user = (""); 
    int ai = 0; 
    String aiPlay = (""); 

    do 
    { 
     ai = rand.nextInt(3) + 1; 

     switch (ai) //was if statements but java suggested to change to switch statements 
     { 
      case 1: 
       aiPlay = ("Rock"); 
       break; 
      case 2: 
       aiPlay = ("Paper"); 
       break; 
      default: 
       aiPlay = ("Scissors"); 
       break; 
     } 

     do //make sure input is correct 
     { 
      System.out.print("rock, paper, or scissors: "); 
      user = input.next(); 
     }while(!(user.equals("rock") || user.equals("paper") || user.equals("scissors"))); 

     if(user.equals(ai)) 
     { 
     System.out.println("You played " + user + ".\nThe computer player " + aiPlay + ".\nIt was a tie!"); 
     System.out.print("Continue? (y or n): "); 
     replay = input.next(); 
     } 
     switch (user) { //was if statements java suggested it change to switch statement 
      case "rock": 
       if (aiPlay.equals("scissors")) 
       { 
        System.out.println("You played " + user + ".\nThe computer player " + aiPlay + ".\nYou win!"); 
        System.out.print("Continue? (y or n): "); 
        replay = input.next(); 
       } 

       else if (aiPlay.equals("paper")) 
       { 
        System.out.println("You played " + user + ".\nThe computer player " + aiPlay + ".\nYou lose!"); 
        System.out.print("Continue? (y or n): "); 
        replay = input.next(); 
       } break; 
      case "paper": 
       if (aiPlay.equals("scissors")) 
       { 
        System.out.println("You played " + user + ".\nThe computer player " + aiPlay + ".\nYou win!"); 
        System.out.print("Continue? (y or n): "); 
        replay = input.next(); 
       } 

       else if (aiPlay.equals("rock")) 
       { 
        System.out.println("You played " + user + ".\nThe computer player " + aiPlay + ".\nYou lose!"); 
        System.out.print("Continue? (y or n): "); 
        replay = input.next(); 
       } break; 
      case "scissors": 
       if (aiPlay.equals("paper")) 
       { 
        System.out.println("You played " + user + ".\nThe computer player " + aiPlay + ".\nYou win!"); 
        System.out.print("Continue? (y or n): "); 
        replay = input.next(); 
       } 

       else if (aiPlay.equals("rock")) 
       { 
        System.out.println("You played " + user + ".\nThe computer player " + aiPlay + ".\nYou lose!"); 
        System.out.print("Continue? (y or n): "); 
        replay = input.next(); 
       } break; 
      default: 
       break; 
     } 

    }while(replay.equals("y")); 
} 

Answer 1

switch (ai) //was if statements but java suggested to change to switch 
statements 
    { 
     case 1: 
      aiPlay = ("rock"); /* All should be lowercase*/ 
      break; 
     case 2: 
      aiPlay = ("paper"); /* All should be lowercase*/ 
      break; 
     default: 
      aiPlay = ("scissors"); /* All should be lowercase*/ 
      break; 
    }