java - 扫描正在输入的字符串

Question

这段代码永远不会打印我是赢了，输了，还是平局，我无法弄清楚。我知道 hischoice 和 Whichpick 都设置正确，但 if 似乎不起作用。我是否错误地使用了字符串或者我对它们进行了错误的比较？我是 Java 新手，所以我不太确定我做错了什么。

import java.util.Scanner;
import java.util.Random;
public class rps {

public static void main(String[] args) {
    int oppchoice;
    String hischoice = "";
    String whichpick;
    String rock = "rock";
    String paper = "paper";
    String scissors = "scissors";
    Scanner mS = new Scanner(System.in);
    Random mR = new Random();

    System.out.print("Type your choice (rock/paper/scissors): ");
    whichpick = mS.nextLine();

    oppchoice = mR.nextInt(3) + 1;
    if (oppchoice == 1) {
        hischoice = rock;
    }
    if (oppchoice == 2) {
        hischoice = paper;
    }
    if (oppchoice == 3) {
        hischoice = scissors;
    }
    System.out.println(hischoice);

    if ((hischoice == rock) && (whichpick == paper)) {
        System.out.println("You win! :)");
    }
    if ((hischoice == paper) && (whichpick == scissors)) {
        System.out.println("You win! :)");
    }
    if ((hischoice == scissors) && (whichpick == rock)) {
        System.out.println("You win! :)");
    }
    if ((hischoice == rock) && (whichpick == scissors)) {
        System.out.println("You lose! :(");
    }
    if ((hischoice == paper) && (whichpick == rock)) {
        System.out.println("You lose! :(");
    }
    if ((hischoice == scissors) && (whichpick == paper)) {
        System.out.println("You lose! :(");
    }
    if ((hischoice == rock) && (whichpick == rock)) {
        System.out.println("It's a tie! :|");
    }
    if ((hischoice == scissors) && (whichpick == scissors)) {
        System.out.println("It's a tie! :|");
    }
    if ((hischoice == paper) && (whichpick == paper)) {
        System.out.println("It's a tie! :|");
    }
}   

}

Answer 1

== 运算符检查两个对象是否完全相同。两个字符串是不同的对象，但具有相同的值(其中具有完全相同的字符)。因此，可以使用 .equals() 方法来比较字符串是否相等，或者使用 .compareTo() 方法来测试不相等的比较。在这种情况下，使用 .equals() 会更容易。

所以这是应该如何完成

if ((hischoice.equals(rock)) && (whichpick.equals(rock))) {
        System.out.println("It's a tie! :|");
    }