对不起，如果在某个地方之前有人问过这个问题，但我真的没有看到任何有助于解决我所遇到的问题的事情。这是为了学校的工作，但是我试图弄清楚我做错了什么，我已经打了两天自己，所以如果有人可以提供帮助，我会非常感激。
我有一个程序，基本上应该输入两个销售人员的名字，显示他们的潜在收入表，最后比较他们的销售差异。我在NetBeans IDE中这样做，并且我在这里有各种各样的东西试图找出它。
一切正常，直到我尝试从ArrayLists中提取任何内容。我当时认为应该可以在那里存放一些东西，然后把它拉出去做我需要做的数学但是我一定做错了。以下是我遇到问题的特定类代码：
class EarningDifference {
SalesPerson persons = new SalesPerson(); //Access to SalesPerson class
AnnualSales aSaleC = new AnnualSales(); //Access to AnnualSales class
ArrayList<SalesPerson> list = new ArrayList<>(); //Access to SalesPerson ArrayList
ArrayList<AnnualSales> aSales = new ArrayList<>(); //Access to AnnualSales ArrayList
AnnualSales person1EarningStr; //Person one earnings from AnnualSales ArrayList
AnnualSales person2EarningStr; //Person two earnings from AnnualSales ArrayList
Double person1Earning; //Person one earnings as double
Double person2Earning; //Person two earnings as double
String person1; //String for person one full name
String person2; //String for person two full name
Double difference; //Variable to store the difference between Person1 and Person2 sales
double totalSales; //variable for Total sales
public void people() {
person1 = list.get(0).getFirstName() + " " + list.get(0).getLastName();
person2 = list.get(1).getFirstName() + " " + list.get(1).getLastName();
System.out.println("Comparing " + person1 + " with " + person2 + ".");
}
void settotalSales(Double totalSales) {
this.totalSales = totalSales;
AnnualSales person1EarningStr = aSales.get(0);
AnnualSales person2EarningStr = aSales.get(1);
double person1Earning = person1EarningStr.doubleValue();
double person2Earning = person2EarningStr.doubleValue();
if (aSales.size() < 2) {
System.out.println("Need another person to compare");
} else if (person1Earning > person2Earning) {
difference = person1Earning - person2Earning;
System.out.println(person1 + " has earned " + difference + " more in sales than " + person2 + ".");
} else {
difference = person2Earning - person1Earning;
System.out.println(person2 + " has earned " + difference + " more in sales than " + person1 + ".");
}
}
}
以下是将项添加到AnnualSales ArrayList的类：
public class SalaryTotal {
double fixedSalary; //Variable for the fixed salary amount
double commission; //Variable for the comission
double minimumSales; //Variable to define the minimum amount of annual sales sales persn must make to receive compensation
double maximumSales; //Variable to define the number after which commission increases
double advanceRate; //Variable used to define the rate at which compensation increases after minimum sales are met
double compensation; //Variable for the amount of compensation based on sales
double totalSalary; //Variable for the total salary
double totalSales;
Double compensationD;
SalesPerson persons = new SalesPerson();
ArrayList<SalesPerson> list = new ArrayList<>();
ArrayList<Double> aSales = new ArrayList<>();
public void getCompensation(double totalSales) {
commission = .21; //The constant commission rate
minimumSales = 120000; //The constant minimum sales needed to receive compensation
maximumSales = 150000; //The constant maximum amount above which commission increases by the advanceRate
advanceRate = 1.67; //The constant at which compensation increasea after minimum sales
this.totalSales = totalSales;
if (totalSales < minimumSales) {
compensation = 0; //sets compensation to 0 if minimum sales are not met
} else if (totalSales <= 150000){
compensation = totalSales * commission + fixedSalary; //calculates total of compensation if total sales meet minimum sales
} else if (totalSales > maximumSales) {
compensation = totalSales * commission * advanceRate + fixedSalary; //calculates total compensation if total sales exceed maximum sales
}
Double compensationD = new Double(compensation);
aSales.add(compensationD);
System.out.println("Current total compensation:" + compensation);
for (int i = 0; i < aSales.size(); i++) {
System.out.println(aSales.get(i));
System.out.println("Show " + persons.makePerson1() + ".");
}
}
}
}
我确定这是一个完整的错误编码，但任何帮助都会受到赞赏，只需忽略我输入的奇数编码的随机位，试图缩小我的问题范围。非常感谢你。
程序的其余部分看起来像这样，我还删除了以前部分中用于问题测试的位
主：
import java.util.Scanner; //Needed for scanner input
import java.text.DecimalFormat; //Needed for correct output of decimals
import java.util.ArrayList;
public class AnnualCompensation {
private static String Y;
public static void main(String[] args) {
DecimalFormat df = new DecimalFormat("$###,###.00"); //This will correctly format the money amounts
Double totalSales;
int startY;
ArrayList<SalesPerson> list = new ArrayList<>();
ArrayList<AnnualSales> aSales = new ArrayList<AnnualSales>();
Scanner start = new Scanner(System.in); //Creates scanner input
System.out.println("Are you ready to compare sales? Press 1 if yes, 2 if no."); //Prints out entry command
startY = start.nextInt();
switch (startY){
case 1:
InputClass inputs = new InputClass();
inputs.getInputs();
break;
case 2:
System.out.println("Thank you anyway!");
System.exit(0);
break;
default:
System.out.println("You have selected neither Y or N, please try again.");
System.exit(0);
}
SalaryTotal calculator = new SalaryTotal(); //Calls class SalaryTotal
PossibleCompensation table = new PossibleCompensation(); //Calls class PossibleCompensation
}
}
可能的补偿：
public class PossibleCompensation {
SalesPerson persons = new SalesPerson();
ArrayList<SalesPerson> list = new ArrayList<>();
ArrayList<AnnualSales> aSales = new ArrayList<AnnualSales>();
DecimalFormat df = new DecimalFormat("$###,###.00"); //This will correctly format the money amounts
double commission; //Variable for the comission
double minimumSales; //Variable to define the minimum amount of annual sales sales persn must make to receive compensation
double maximumSales; //Variable to define the number after which commission increases
double advanceRate; //Variable used to define the rate at which compensation increases after minimum sales are met
double compensation; //Variable for the amount of compensation based on sales
double totalSales; //Variable for sales person annual sale
public void settotalSales(double totalSales) {
for (int i = 0; i < list.size(); i++)
this.totalSales = totalSales; //Sets the input from AnnualCompensation to totalSales in this class
commission = .21; //The constant commission rate
minimumSales = 120000; //The constant minimum sales needed to receive compensation
maximumSales = 150000; //The constant maximum amount above which commission increases by the advanceRate
advanceRate = 1.67; //The constant at which compensation increasea after minimum sales
String heading1 = "Total Sales"; //variable to print a header for the table
String heading2 = "Total Compensation"; //variable to print a header for the table
System.out.print("\nBelow is a table based on possible commissions if sales increase:\n"); //Prints instructions
System.out.printf("\n%20s %20s", heading1, heading2); //prints header and formats spacing
for (double i=totalSales; i <= (totalSales * 1.5); i+= 5000) { //FOR loop for calculating and constructing table
if (i < minimumSales) {
compensation = 0; //sets compensation to 0 if minimum sales are not met
} else if (i <= 150000){
compensation = i * commission; //calculates total of compensation if total sales meet minimum sales
} else if (i > maximumSales) {
compensation = i * commission * advanceRate; //calculates total compensation if total sales exceed maximum sales
}
System.out.printf("\n%20s %15s", df.format(i), df.format(compensation) + "\n"); //Prints out the table
}
}
}
class SalesPerson {
String firstName;
String lastName;
String totalSalesStr;
ArrayList<SalesPerson> list = new List<>();
SalesPerson类：
public SalesPerson() {
this.firstName = firstName;
this.lastName = lastName;
this.totalSalesStr = totalSalesStr;
}
SalesPerson(String firstName, String lastName, String totalSalesStr) {
this.firstName = firstName;
this.lastName = lastName;
this.totalSalesStr = totalSalesStr;
}
public String getFirstName() {
return this.firstName;
}
public String getLastName() {
return this.lastName;
}
public String getTotalSalesStr() {
return this.totalSalesStr;
}
public Double getTotalSales() {
Double totalSales = Double.parseDouble(totalSalesStr);
return totalSales;
}
public String makePerson1() {
String person1 = list.get(0).getFirstName() + " " + list.get(0).getLastName();
return person1;
}
public String makePerson2() {
String person2 = list.get(1).getFirstName() + " " + list.get(1).getLastName();
return person2;
}
@Override
public String toString() {
return ("Sales person " + this.getFirstName() + " " + this.getLastName() + " has annual sales of " + this.getTotalSalesStr() + ".");
}
}
class AnnualSales {
Double compensationD;
AnnualSales person1EarningStr;
AnnualSales person2EarningStr;
ArrayList<AnnualSales> aSales = new ArrayList<AnnualSales>();
public AnnualSales() {
this.compensationD = compensationD;
}
public AnnualSales(Double compensationD) {
this.compensationD = compensationD;
}
public Double getCompensationD() {
return this.compensationD;
}
public AnnualSales getperson1EarningStr() {
person1EarningStr = aSales.get(0);
return person1EarningStr;
}
public AnnualSales getperson2EarningStr() {
person2EarningStr = aSales.get(1);
return person2EarningStr;
}
@Override
public String toString() {
return ("please show us" + compensationD);
}
}
输入类：
class InputClass {
String firstName;
String lastName;
Double totalSales;
String totalSalesStr;
CopyOnWriteArrayList<SalesPerson> list = new CopyOnWriteArrayList<>();
public void getInputs() {
for(double i=0; i < 2; i++){
Scanner persFN = new Scanner(System.in); //Creates scanner input
System.out.println("Enter sales person's first name:"); //Prints out entry command
String firstName = persFN.next();
Scanner persLN = new Scanner(System.in); //Creates scanner input
System.out.println("Enter sales person's last name:"); //Prints out entry command
String lastName = persLN.next();
Scanner input = new Scanner(System.in); //Creates scanner input
System.out.println("Enter Total Sales:"); //Prints out entry command
totalSales = input.nextDouble();
String totalSalesStr = totalSales.toString();
list.add(new SalesPerson(firstName, lastName, totalSalesStr));
SalaryTotal calculator = new SalaryTotal(); //Calls class SalaryTotal
calculator.getCompensation(totalSales);
PossibleCompensation table = new PossibleCompensation(); //Calls class PossibleCompensation
table.settotalSales(totalSales);
EarningDifference earning = new EarningDifference();
earning.settotalSales(totalSales);
}
}
}
我认为这应该是一切相关的！
答案 0 :(得分：0)
确保在类中使用覆盖equals()方法。作为一种良好做法，请务必确保同时覆盖equals()和hashCode()。
为什么？
来自Java doc。
从此列表中删除第一次出现的指定元素， 如果它存在。如果列表不包含该元素，则为 不变。更正式地，删除具有最低索引i的元素 这样（o == null？get（i）== null：o.equals（get（i）））（如果是这样的话） 元素存在）。如果此列表包含指定的，则返回true element（或等效地，如果此列表由于更改而更改） 呼叫）。
如果您的ArrayList元素不是String（更一般地说，如果它不是内置Java类），则需要覆盖equals()方法。