scanner.next（）不停止

Question

public class ElectronicCounter { 

    public ElectronicCounter(User user)throws IOException{ 
     Scanner scanner = new Scanner(System.in); 
     boolean done = false; 
     loginName = user.getName(); 

     System.out.println("--------------------------------------------------------"); 
     System.out.println("Welcome to the Electronic-Sales Counter! "); 

     while(!done){ 
      try{ 
       System.out.print("Please enter '1' to record sales or '2' to exit:"); 
       input = scanner.nextLine(); 
       System.out.println("bug"); 
       if(input=="1"){ 
        System.out.println("Please enter a list of purchasing-product ID and number"); 
        done = true; 
       } 
       else if(input=="2"){ 
        System.out.println("<LOG> User " +loginName+ " has successfully logged off! "); 
        done = true; 
       } 
       else{ 
        System.out.println("<LOG> Invalid command"); 
       } 
      } 
      catch (NoSuchElementException e){ 
       System.out.println("<LOG> No Such Element"); 
      } 
      catch (IllegalStateException e){ 
       System.out.println("<LOG> IllegalState"); 
      } 
     } 
     scanner.close(); 
    } 

    static String loginName; 
    static String input; 
} 

當計算scanner.nextLine()時，掃描器不停止搜索令牌。我想問問怎樣才能停止掃描器等待輸入??謝謝

Answer 1

從不比較字符串使用==。當使用==來比較字符串對象時，您並未比較它的值，但它是引用。

始終使用equals方法進行比較。

input.equals("2");