我正在创建一个计算年度降雨量的程序等。我在下面的第一个代码块中完美地处理了用户输入。但是，我现在尝试更改程序，以便指定数组值（我基本上试图消除用户输入）。
为什么第二块代码不起作用？我在r.getTotalRainFall，r.getAverageRainFall等底部收到错误。
请注意我必须引入数组thisYear（这是必需的）。
代码块＃1：
import java.util.*;
public class Rainfall {
Scanner in = new Scanner(System.in);
int month = 12;
double total = 0;
double average;
double months[];
public Rainfall() {
months = new double[12];
}
public void enterMonthData() {
for (int n = 1; n <= month; n++) {
System.out.print("Enter the rainfall (in inches) for month #" + n + ": ");
months[n - 1] = in.nextDouble();
// Input Validation - Cannot accept a negative number
while (months[n - 1] < 0) {
System.out.print("Rainfall must be at least 0. Please enter a new value.");
months[n - 1] = in.nextDouble();
}
}
}
public double getTotalRainFall() {
total = 0;
for (int i = 0; i < 12; i++) {
total = total + months[i];
}
return total;
}
public double getAverageRainFall() {
average = total / 12;
return average;
}
/**
* Returns the index of the month with the highest rainfall.
*/
public int getHighestMonth() {
int highest = 0;
for (int i = 0; i < 12; i++) {
if (months[i] > months[highest]) {
highest = i;
}
}
return highest;
}
/**
* Returns the index of the month with the lowest rainfall.
*/
public int getLowestMonth() {
int lowest = 0;
for (int i = 0; i < 12; i++) {
if (months[i] < months[lowest]) {
lowest = i;
}
}
return lowest;
}
public static void main(String[]args) {
Rainfall r = new Rainfall();
r.enterMonthData();
System.out.println("The total rainfall for this year is " + r.getTotalRainFall());
System.out.println("The average rainfall for this year is " + r.getAverageRainFall());
int lowest = r.getLowestMonth();
int highest = r.getHighestMonth();
System.out.println("The month with the highest amount of rain is " + (highest+1) + " with " + r.months[highest] + " inches");
System.out.println("The month with the lowest amount of rain is " + (lowest+1) + " with " + r.months[lowest] + " inches");
}
}
代码块＃2：
package rain;
public class Rain {
int month = 12;
double total = 0;
double average;
double getRainAt[];
public Rain {
getRainAt = new double[12];
}
double getTotalRainFall() {
total = 0;
for (int i = 0; i < 12; i++) {
total = total + getRainAt[i];
}
return total;
}
double getAverageRainFall() {
average = total / 12;
return average;
}
int getHighestMonth() {
int high = 0;
for (int i = 0; i < 12; i++) {
if (getRainAt[i] > getRainAt[high]) {
high = i;
}
}
return high;
}
int getLowestMonth() {
int low = 0;
for (int i = 0; i < 12; i++) {
if (getRainAt[i] < getRainAt[low]) {
low = i;
}
}
return low;
}
public static void main(String[] args) {
// Create an array of rainfall figures.
double[] thisYear = {1.6, 2.1, 1.7, 3.5, 2.6, 3.7,
3.9, 2.6, 2.9, 4.3, 2.4, 3.7 };
int high; // The high month
int low; // The low month
// Create a RainFall object initialized with the figures
// stored in the thisYear array.
Rainfall r = new Rainfall(thisYear);
// Display the statistics.
System.out.println("The total rainfall for this year is " +
r.getTotalRainFall();
System.out.println("The average rainfall for this year is " +
r.getAverageRainFall());
high = r.getHighestMonth();
System.out.println("The month with the highest amount of rain " +
"is " + (high+1) + " with " + r.getRainAt(high) +
" inches.");
low = r.getLowestMonth();
System.out.println("The month with the lowest amount of rain " +
"is " + (low+1) + " with " + r.getRainAt(low) +
" inches.");
}
}
}
答案 0 :(得分：2)
我重新考虑了2个班级
现在Rain类只包含main方法，而所有其他逻辑都包含在Rainfall类
中Rainfall类有一个方法 - getRainAt（）来获取给定月份的降雨量 在Rainfall类中有一个构造函数，它将一个double数组作为参数，因此必须使用提供的参数进行实例化。
立即查看课程，看看这是否符合您的要求。
import java.util.*;
public class Rainfall {
Scanner in = new Scanner(System.in);
int month = 12;
double total = 0;
double average;
double months[];
public Rainfall(double newmonths[]){
months = newmonths;
}
public void enterMonthData() {
for (int n = 1; n <= month; n++) {
System.out.print("Enter the rainfall (in inches) for month #" + n
+ ": ");
months[n - 1] = in.nextDouble();
// Input Validation - Cannot accept a negative number
while (months[n - 1] < 0) {
System.out
.print("Rainfall must be at least 0. Please enter a new value.");
months[n - 1] = in.nextDouble();
}
}
}
public double getTotalRainFall() {
total = 0;
for (int i = 0; i < 12; i++) {
total = total + months[i];
}
return total;
}
public double getAverageRainFall() {
average = total / 12;
return average;
}
/**
* get rain given the month number
*/
public double getRainAt(int month){
double rainValue = 0;
for (int i = 0; i < months.length; i++) {
if(month == i){
rainValue = months[i];
break;
}
}
return rainValue;
}
/**
* Returns the index of the month with the highest rainfall.
*/
public int getHighestMonth() {
int highest = 0;
for (int i = 0; i < 12; i++) {
if (months[i] > months[highest]) {
highest = i;
}
}
return highest;
}
/**
* Returns the index of the month with the lowest rainfall.
*/
public int getLowestMonth() {
int lowest = 0;
for (int i = 0; i < 12; i++) {
if (months[i] < months[lowest]) {
lowest = i;
}
}
return lowest;
}
}
Rain class现在只有主要方法
public class Rain {
public static void main(String[] args) {
// Create an array of rainfall figures.
double[] thisYear = { 1.6, 2.1, 1.7, 3.5, 2.6, 3.7, 3.9, 2.6, 2.9, 4.3,
2.4, 3.7 };
int high; // The high month
int low; // The low month
// Create a RainFall object initialized with the figures
// stored in the thisYear array.
Rainfall r = new Rainfall(thisYear);
// Display the statistics.
System.out.println("The total rainfall for this year is "
+ r.getTotalRainFall());
System.out.println("The average rainfall for this year is "
+ r.getAverageRainFall());
high = r.getHighestMonth();
System.out.println("The month with the highest amount of rain " + "is "
+ (high + 1) + " with " + r.getRainAt(high) + " inches.");
low = r.getLowestMonth();
System.out.println("The month with the lowest amount of rain " + "is "
+ (low + 1) + " with " + r.getRainAt(low) + " inches.");
}
}
希望这会有所帮助
答案 1 :(得分：1)
不确定为什么要创建一个getRainAt类来初始化它，尝试使用Rain类构造函数来执行此操作。
替换它：
public class getRainAt {
public getRainAt() {
getRainAt = new double[12];
}
}
使用：
public Rain() {
getRainAt = new double[12];
}
因为你现在使用的是Rain而不是Rainfall，所以在main方法中它应该是： Rain r = new Rain（）;
答案 2 :(得分：1)
我不确定这只是一个复制错误，但是在第二个块中你调用了类Rain，但是你将r声明为Rainfall。