java - ArrayList 中的 "Duplicate"条目？

Question

我有一个类，它将用数组中预先创建的所有员工填充一个列表。我可以用员工填充 ArrayList，但唯一的问题是我得到一些“重复”条目，我使用引号，因为它们不完全相同，但他们可以共享相同的姓名或员工编号，但可能没有相同的雇用年份或工资等。

这是员工类别:

public class Employee {

public String EmployeeName;
public String EmployeeNumber;
public int hireyear;
public double WeeklyEarning;

public Employee()
{
    EmployeeName = null;
    EmployeeNumber = null;
    hireyear = 0;
    WeeklyEarning = 0;

}

public static final String[] Empnum = new String[] {
        "0001-A", "0002-B","0003-C","0004-D","0002-A",
        "0003-B","0004-C","0005-D","0011-A", "0012-B",
        "0013-C","0014-D","0121-A", "0122-B","0123-C",
        "0321-A", "0312-B","1234-D","4321-C","1122-D"};

public static final String[] Ename = new String[] {
        "Josh", "Alex", "Paul", "Jimmy", "Josh", "Gordan", "Neil", "Bob",
        "Shiv", "James", "Jay", "Chris", "Michael", "Andrew", "Stuart",
        "Dave","Benjamin","Dan","Brian","Michelle"};

public String getEmployeeName()
{
    return this.EmployeeName;
}

public String getEmployeeNumber()
{
    return this.EmployeeNumber;
}

public int gethireyear()
{
    return this.hireyear;
}

public double getWeeklyEarning()
{
    return this.WeeklyEarning;
}

public String setEmployeeName(String EName)
{
    return this.EmployeeName = EName;
}

public String setEmployeeNumber(String ENumber)
{
    return this.EmployeeNumber = ENumber;
}

public int setEmployeehireyear(int Ehireyear)
{
    return this.hireyear = Ehireyear;
}

public double setEmployeeweeklyearning(double Eweeklyearning)
{
    return this.WeeklyEarning = Eweeklyearning;
}

public String toString(){
    String data = "\n Employee Name : " + EmployeeName + " \n Employee Number: " + EmployeeNumber + " \n Hire Year : " + hireyear + "\n Weekly Earnings : " + WeeklyEarning;
    return data;
}

public boolean equals(Object o){
    if(this == null){
        return false;
    }
    if(this == o){
        return true;
    }
    if(!(o instanceof Employee)){
        return false;
    }

    Employee temp = (Employee) o;
    if(this.getEmployeeName().equals(temp.getEmployeeName())){
        return true;

    }
    if(this.getEmployeeNumber().equals(temp.getEmployeeNumber())){
        return true;

    }
    if(this.gethireyear() == temp.gethireyear()){
        return true;
    }
    if(this.getWeeklyEarning() == temp.getWeeklyEarning()){
        return true;
    }
    return false;

}

}

这是将填充列表的generateList方法:

public ArrayList<Employee> generateEmpList(){
    empList = new ArrayList <Employee>();
    Random empPicker = new Random();

    for(int i = 0; i < 20; i++){
        int id = empPicker.nextInt(20);
        if(id < 12) // roll for production worker
        {

            //System.out.println("Adding Production Worker");
            ProductionWorker temp = new ProductionWorker();
            temp = temp.generateProductionWorker();
            prodWorker = temp;
            empList.add(prodWorker);

        }
        else //roll for Shift supervisor
        {
            //System.out.println("Adding Shift supervisor");
            ShiftSupervisor supervisor = new ShiftSupervisor();
            supervisor = supervisor.generateShiftSupervisor();
            shiftWorker = supervisor;
            empList.add(shiftWorker);
        }
    }
    Iterator iterator = empList.iterator();
    while (iterator.hasNext()) {
        System.out.println("");
        System.out.println(iterator.next());

    }
    return empList;
}

另外可能有用的是“generateProductionWorker()”和shiftSupervisor方法 - 为了保持简短，只有后期生产工作人员方法，因为它们基本上是相同的:

public ProductionWorker generateProductionWorker(){
    Random rng = new Random();
    int numberOfEmployeeNames = Ename.length;
    ProductionWorker tempPworker = new ProductionWorker();

    String employeeName = Ename[rng.nextInt(numberOfEmployeeNames)];
    tempPworker.setEmployeeName(employeeName);

    int numberOfEmployeeNumbers = Empnum.length;
    String employeeNumber = Empnum[rng.nextInt(numberOfEmployeeNumbers)];
    tempPworker.setEmployeeNumber(employeeNumber);

    int yearHired = rng.nextInt(35) + 1980;
    tempPworker.setEmployeehireyear(yearHired);

    double weeklySalary = rng.nextInt((100) * 100);
    tempPworker.setEmployeeweeklyearning(weeklySalary);

    int hourlyRate = rng.nextInt(20) + 10;
    tempPworker.setHourlyRate(hourlyRate);

    return tempPworker;

}

我确信我错过了一些微不足道的东西，但你知道为什么当我有 20 个姓名和号码的列表时我会得到类似的条目吗？

例如: 员工姓名 - 乔什 empnum - 0000-A 雇佣年份 - 1994 工资 - 40,000

员工姓名 - 乔什 empnum - 0000-A 雇佣年份 - 1999 工资 - 60,500

任何建议都会有所帮助，谢谢!

Answer 1

查看 Employee 类中的 equals 方法。如果它们的名字相同，则返回 true，这意味着它们是相等的。其他属性也是如此。您必须替换 if 语句。