我的Java方法运行不正确，导致程序编译错误_Java

我的Java方法运行不正确，导致程序编译错误

java

我的Java方法运行不正确，导致程序编译错误,java,Java,我正在编写一个程序，它将提示用户输入一个温度作为整数，然后提示用户选择该温度的刻度，可以是华氏度、摄氏度或开尔文。然后，它会提示用户从3个比例选择中选择要转换为的温度，然后计算转换并显示最终温度。我的程序目前正在运行，但运行不正确，我已经盯着它看了好几天了，我不知道它为什么会这样编译。我对编码还是相当陌生，这是一个课堂作业，我一直在寻找一些建议封装温度转换器；导入java.util.* 公共类临时转换器 { 下面是它编译的内容运行：输入要转换为100的温度您当前的体温是多少度？1:Fa

我正在编写一个程序，它将提示用户输入一个温度作为整数，然后提示用户选择该温度的刻度，可以是华氏度、摄氏度或开尔文。然后，它会提示用户从3个比例选择中选择要转换为的温度，然后计算转换并显示最终温度。我的程序目前正在运行，但运行不正确，我已经盯着它看了好几天了，我不知道它为什么会这样编译。我对编码还是相当陌生，这是一个课堂作业，我一直在寻找一些建议

封装温度转换器；导入java.util.*

公共类临时转换器 {

下面是它编译的内容

运行：输入要转换为100的温度您当前的体温是多少度？1:Fahrenheit2:Celsius 3:Kelvin请输入1、2或3：您希望转换为多少度？1:Fahrenheit2:Celsius 3:Kelvin请输入1、2或3：您当前的体温是多少度？1:Fahrenheit2:Celsius 3:Kelvin请输入1、2或3：您当前的体温是多少度？1:Fahrenheit2:Celsius 3:KElvin请输入1、2或3：您当前的体温是什么刻度？1：华氏2:Celsius 3:Kelvin请输入1、2或3：您当前的体温是什么刻度？1：华氏2:Celsius 3:Kelvin请输入1、2或3：您当前的体温是什么刻度？1：华氏2:Celsius 3:Kelvin请输入1、2或3：输入温度以转换2 您希望转换为什么刻度？1:Fahrenheit2:Celsius3:Kelvin请输入1、2或3：您的最终温度为：-274.15您的选择有误！生成成功（总时间：33秒）

这就好像它没有按照正确的顺序编译，或者没有按照正确的顺序获取正确的信息，并且一次又一次地获取一些信息。一旦你输入数字温度，它会提示你输入刻度，但不仅仅是一次它打印了很多次，然后你输入你对第一个刻度的选择，它会一直显示到to完成，无需输入您的toScale选择

public static void main(String[] args)
{


    String scaleOne;
    String scaleTwo;

    System.out.println("What scale is your temp currently in?\n"+
            "1: Fahrenheit\n" +
            "2: Celsius\n" +
            "3: Kelvin\n" +
            "Please enter 1, 2, or 3: \n");

    scaleOne = getScale();

    System.out.println("What scale would you like to convert to?\n"+
            "1: Fahrenheit\n" +
            "2: Celsius\n" +
            "3: Kelvin\n" +
            "Please enter 1, 2, or 3:\n ");

    scaleTwo = getScale();
    System.out.print("Your final temp is: " +convert(scaleOne,scaleTwo));


}
private static double getTemp()
{
    double temp;
    Scanner userIn= new Scanner(System.in);
    System.out.print("Enter a temperature to convert ");
    while(!userIn.hasNextDouble())
    {
        System.out.println("That is not a valid temperature!");
        System.out.println("Re-enter a temperature: ");
        userIn.next();
    }
    temp=userIn.nextDouble();

    return temp;
}

private static String getScale()
{

    Scanner userIn= new Scanner(System.in);

    String scale="";

    switch(userIn.nextInt())
    {
        case 1:
            scale= "Fahrenheit";
            break;

        case 2:
            scale="Celsius";
            break;

        case 3:
            scale="Kelvin";
            break;

        default:
            scale= "There was an error in your choice!";
    }

    return scale;

}

相应地更改main函数以及scaleone（）和toScale（）函数。您的代码中存在许多无法单独解决的问题。请随时询问有关答案的任何澄清

相应地更改main函数以及scaleone（）和toScale（）函数。您的代码中存在许多无法单独解决的问题。请随时询问有关答案的任何说明

请参阅下面代码中插入的注释和更正

public class TempConverter {

    // variables that are needed in more than one method must be declared outside the methods
    // (static since the methods are static; not recommended, but let it be for now)
    static double temp1;
    static String scale1;
    static String scale2;

    public static void main(String[] args) {
        // get rid of unused variables
        char cont = 'E';

        do {
            // input
            // save all inputs to variables
            temp1 = getTemp();
            // Java parameters are pass by value, so to get a value out of the method, use the returned value
            // then you don’t need the parameter
            scale1 = scaleOne();
            scale2 = toScale();

            // process
            // don’t call toScale() again, or the user will be prompted again,
            // instead, use the value already stored in scale2
            System.out.print("Your final temp is: " + convert() + ' ' + scale2);

            // you should set cont to something if you want the loop to repeat

        } while (cont == 'N');
    }

    private static double getTemp() {
        double temp;
        Scanner userIn = new Scanner(System.in);
        System.out.print("Enter a temperature to convert ");
        while (!userIn.hasNextDouble()) {
            System.out.println("That is not a valid temperature!");
            System.out.print("Re-enter a temperature: ");
            userIn.next();
        }
        temp = userIn.nextDouble();

        return temp;
    }

    private static String scaleOne() {

        Scanner userIn = new Scanner(System.in);

        // \n is a line break for readability
        System.out.print("What scale is your temp currently in?" 
                + "\n1: Fahrenheit" 
                + "\n2: Celsius" 
                + "\n3: Kelvin"
                + "\nPlease enter 1, 2, or 3: ");

        // read a value from the user
        int userChoice = userIn.nextInt();

        String scale = "";

        switch (userChoice) {
        case 1: {
            scale = "Fahrenheit";
            break;
        }

        case 2: {
            scale = "Celsius";
            break;
        }

        case 3: {
            scale = "Kelvin";
            break;
        }

        default: {
            scale = "There was an error in your choice!";
        }
        }

        return scale;

    }

    private static String toScale() {

        Scanner userIn = new Scanner(System.in);

        System.out.print("What scale would you like to convert to?" + "1: Fahrenheit" + "2: Celsius" + "3: Kelvin"
                + "Please enter 1, 2, or 3: ");

        String scale2 = "";

        int userChoice = userIn.nextInt();

        // ideally should not accept the same scale as scale1 (from scale)
        switch (userChoice) {
        case 1: {
            scale2 = "Fahrenheit";
            break;
        }

        case 2: {
            scale2 = "Celsius";
            break;
        }

        case 3: {
            scale2 = "Kelvin";
            break;
        }

        default: {
            scale2 = "There was an error in your choice!";
        }
        }

        return scale2;

    }

    public static double convert() {
        // need only one variable for result
        double converts;

        // don’t call methods again, use variables
        // don’t use == for comparing strings, use .equals
        // typo: the second scale corrected to scale2
        if (scale1.equals("Fahrenheit") && scale2.equals("Kelvin")) {
            // don’t call getTemp() again
            converts = (temp1 + 459.67) * 5 / 9;
        }

        else if (scale1.equals("Fahrenheit") && scale2.equals("Celsius")) {
            converts = (temp1 - 32) * 5 / 9;
        }

        else if (scale1.equals("Celsius") && scale2.equals("Kelvin")) {
            converts = temp1 + 273.15;
        }

        else if (scale1.equals("Celsius") && scale2.equals("Fahrenheit")) {
            converts = temp1 * 9 / 5 + 32;
        }

        else if (scale1.equals("Kelvin") && scale2.equals("Fahrenheit")) {
            converts = temp1 * 9 / 5 - 459.67;
        }

        else { // Kelvin to Celsius
            converts = temp1 - 276.15;
        }

        return converts;
    }

}

我相信它现在基本上可以工作。

请参阅下面代码中插入的注释和更正

public class TempConverter {

    // variables that are needed in more than one method must be declared outside the methods
    // (static since the methods are static; not recommended, but let it be for now)
    static double temp1;
    static String scale1;
    static String scale2;

    public static void main(String[] args) {
        // get rid of unused variables
        char cont = 'E';

        do {
            // input
            // save all inputs to variables
            temp1 = getTemp();
            // Java parameters are pass by value, so to get a value out of the method, use the returned value
            // then you don’t need the parameter
            scale1 = scaleOne();
            scale2 = toScale();

            // process
            // don’t call toScale() again, or the user will be prompted again,
            // instead, use the value already stored in scale2
            System.out.print("Your final temp is: " + convert() + ' ' + scale2);

            // you should set cont to something if you want the loop to repeat

        } while (cont == 'N');
    }

    private static double getTemp() {
        double temp;
        Scanner userIn = new Scanner(System.in);
        System.out.print("Enter a temperature to convert ");
        while (!userIn.hasNextDouble()) {
            System.out.println("That is not a valid temperature!");
            System.out.print("Re-enter a temperature: ");
            userIn.next();
        }
        temp = userIn.nextDouble();

        return temp;
    }

    private static String scaleOne() {

        Scanner userIn = new Scanner(System.in);

        // \n is a line break for readability
        System.out.print("What scale is your temp currently in?" 
                + "\n1: Fahrenheit" 
                + "\n2: Celsius" 
                + "\n3: Kelvin"
                + "\nPlease enter 1, 2, or 3: ");

        // read a value from the user
        int userChoice = userIn.nextInt();

        String scale = "";

        switch (userChoice) {
        case 1: {
            scale = "Fahrenheit";
            break;
        }

        case 2: {
            scale = "Celsius";
            break;
        }

        case 3: {
            scale = "Kelvin";
            break;
        }

        default: {
            scale = "There was an error in your choice!";
        }
        }

        return scale;

    }

    private static String toScale() {

        Scanner userIn = new Scanner(System.in);

        System.out.print("What scale would you like to convert to?" + "1: Fahrenheit" + "2: Celsius" + "3: Kelvin"
                + "Please enter 1, 2, or 3: ");

        String scale2 = "";

        int userChoice = userIn.nextInt();

        // ideally should not accept the same scale as scale1 (from scale)
        switch (userChoice) {
        case 1: {
            scale2 = "Fahrenheit";
            break;
        }

        case 2: {
            scale2 = "Celsius";
            break;
        }

        case 3: {
            scale2 = "Kelvin";
            break;
        }

        default: {
            scale2 = "There was an error in your choice!";
        }
        }

        return scale2;

    }

    public static double convert() {
        // need only one variable for result
        double converts;

        // don’t call methods again, use variables
        // don’t use == for comparing strings, use .equals
        // typo: the second scale corrected to scale2
        if (scale1.equals("Fahrenheit") && scale2.equals("Kelvin")) {
            // don’t call getTemp() again
            converts = (temp1 + 459.67) * 5 / 9;
        }

        else if (scale1.equals("Fahrenheit") && scale2.equals("Celsius")) {
            converts = (temp1 - 32) * 5 / 9;
        }

        else if (scale1.equals("Celsius") && scale2.equals("Kelvin")) {
            converts = temp1 + 273.15;
        }

        else if (scale1.equals("Celsius") && scale2.equals("Fahrenheit")) {
            converts = temp1 * 9 / 5 + 32;
        }

        else if (scale1.equals("Kelvin") && scale2.equals("Fahrenheit")) {
            converts = temp1 * 9 / 5 - 459.67;
        }

        else { // Kelvin to Celsius
            converts = temp1 - 276.15;
        }

        return converts;
    }

}

我相信它现在基本上可以工作。

您必须相信编译器的工作是正确的。错误在于您的逻辑。我假设您正在尝试创建一个程序，将温度从3种格式中的任意一种转换为其他格式

调用

scaleOne（scale1）；

方法时，您提供了一个硬编码值

作为参数，并且从未在方法中更改过它。同时，您尝试从用户获取输入。要获取用户输入，您需要在方法体中添加

int-userChoice=userIn.nextInt（）；

。这将返回一个sting值，您需要将其存储在main方法的

sacle1

变量中

类似地，对于

toScale（）

方法，您需要使其非参数化，并从方法内部的用户获取输入。这将再次返回一个sting值，您需要将其存储在main方法的

sacle2

变量中

现在，在调用convert方法时，需要将

scale1

和

scale2

作为参数传递。我不明白调用

scaleOne（）

和

toScale（）背后的逻辑是什么

在每个if条件下再次使用方法。这就是代码一再要求选择温度类型的原因。我已在解决方案中使用

scale1

和

scale2

变量删除了它们。请始终记住，切勿使用

==

运算符进行

String

比较。请始终使用字符串类的

equals（）

或

equalsEgnoreCase（）

方法

我已经对您的代码进行了更改，并尝试根据您的需要获得更具体的解决方案。希望这会有所帮助。别忘了投票支持

    public class TempConverter {
    public static void main(String[] args) 
{
    String scale1;
    String scale2;   
        //input
       scale1 =scaleOne();
       scale2 = toScale();
    //process
    System.out.print("Your final temp is: " +convert(scale1, scale2));
}   
    private static double getTemp()
    {
         double temp;
         Scanner userIn= new Scanner(System.in);
         System.out.print("Enter a temperature to convert ");
         while(!userIn.hasNextDouble())
         {
          System.out.println("That is not a valid temperature!");
          System.out.print("Re-enter a temperature: ");
          userIn.next();
         }
         temp=userIn.nextDouble();
         return temp;
    }

    private static String scaleOne()        {

        Scanner userIn= new Scanner(System.in);
        System.out.print("What scale is your temp currently in?"+
                          "1: Fahrenheit" + 
                          "2: Celsius" + 
                          "3: Kelvin" + 
                          "Please enter 1, 2, or 3: ");
       int userChoice = userIn.nextInt();
        String scale="";
        switch(userChoice)
        {
            case 1:
            {scale= "Fahrenheit";
            break;}
            case 2:
            {scale="Celsius";
            break;}
            case 3:
            {scale="Kelvin";
            break;}
            default:
            {scale= "There was an error in your choice!";}
        }
        return scale;
    }



    private static String toScale(){
        Scanner userIn= new Scanner(System.in);
        System.out.print("What scale would you like to convert to?"+
                          "1: Fahrenheit" + 
                          "2: Celsius" + 
                          "3: Kelvin" + 
                          "Please enter 1, 2, or 3: ");
        String scale2="";
        int userChoice =  userIn.nextInt();
        switch(userChoice)
        {
            case 1:
            {scale2= "Fahrenheit";
            break;}
            case 2:
            {scale2="Celsius";
            break;}
            case 3:
            {scale2="Kelvin";
            break;}
            default:
            {scale2= "There was an error in your choice!";}
        }
        return scale2;
    }

    public static double convert(String scale1, String scale2)
    {       
        double converts;

        if(scale1.equalsIgnoreCase("Fahrenheit") && scale2.equalsIgnoreCase("Kelvin"))        
        {
         converts=(getTemp()+459.67)* 5/9;
        }

        else if(scale1.equalsIgnoreCase("Fahrenheit") && scale2.equalsIgnoreCase("Celsius"))
        {
         converts=(getTemp()-32)*5/9;
        }

        else if(scale1.equalsIgnoreCase("Celsius") && scale2.equalsIgnoreCase("Kelvin"))
        {
         converts=getTemp()+273.15;
        }

        else if(scale1.equalsIgnoreCase("Celsius") && scale2.equalsIgnoreCase("Fahrenheit"))
        {
         converts=getTemp()*9/5+32;
        }

        else if(scale1.equalsIgnoreCase("Kelvin") && scale1.equalsIgnoreCase("Fahrenheit"))
        {
         converts=getTemp()*9/5-459.67;
        }

        else
        { 
         converts=getTemp()-276.15;
        }

        return converts;
    }}