嵌套If语句--未接收预期输出Java

Question

这是一个简单的程序，向用户询问两个问题。根据用户的输入，我们将显示对对象的猜测。类似于游戏“20个问题”。无论我给程序输入什么，它总是以“回形针”的形式返回myGuess的值。

我试着注释掉每个if/ each语句的内部，并将输出设置为1,2,3，但它仍然是3(回形针的块)。这使我认为，我对字符串的比较在用户输入或条件逻辑的赋值方面都有错误.以下是代码：

import java.util.Scanner;

public class JavaTraining {


  public static void main(String[] args) {

      Scanner keyboard = new Scanner(System.in);
      String input1,input2;
      String myGuess;

      System.out.println("TWO QUESTIONS!");

      System.out.println("Think of an object, and I'll try to guess it.\r\n");

      System.out.println("Question 1) Is it an animal, vegetable, or mineral?");
      input1 = keyboard.nextLine();

      System.out.println("\r\nQuestion 2) Is it bigger than a breadbox?");
      input2 = keyboard.nextLine();

      if (input1 == "animal"){

          if (input2 == "yes"){
              myGuess = "moose";
          }
          else{
              myGuess = "squirrel";
          }
      }
      else if (input1 == "vegetable"){
          if (input2 == "yes"){
              myGuess = "watermelon";
          }
          else{
              myGuess = "carrot";
          } 
      }
      else{
          if (input2 == "yes"){
              myGuess = "Camaro";
          }
          else{
              myGuess = "paper clip";
          } 
      }

      System.out.println("\r\nMy guess is that you are think of a "+myGuess+".\r\nI would"
              +" ask you if I'm right, but I don't actually care."+input1+input2);
      }
  }

Answer 1

字符串使用.equals()而不是==。Java字符串是对象，而不是原始数据类型。

改变这个

     if (input1 == "animal")

至

    if(input1.equals("animal"))

看看这个link