Question

我正在编写一个简单的程序来列出JAVA中的公司名称和员工队伍。

我想动态创建对象。以下是代码

public class EmployeeRecord {

/**
 * @param args
 */
String company, name;
int employee;
public String input;
public static BufferedReader br;
public int iE;
public static String numberOfCompanies;
String nameOfCompany;*/

public void company(String input) {
    // TODO Auto-generated method stub

    nameOfCompany = input;
}

public void employee(String employeeNumber) {
    // TODO Auto-generated method stub
    iE = Integer.parseInt(employeeNumber);
}*/

public static void main(String[] args) {
    // TODO Auto-generated method stub

    EmployeeRecord qw = new EmployeeRecord ();
    try {
        br = new BufferedReader(new InputStreamReader(System.in));
        System.out.println("Enter number of companies: ");
        numberOfCompanies = br.readLine();
        int G = Integer.parseInt(numberOfCompanies);

        for (int i = 1; i <= G; i++) {

            System.out.println("Enter name of the company: ");
            String company = br.readLine();
            qw.company(company);
            System.out.println("Enter Number of employees: ");
            String employeeNumber = br.readLine();
            qw.employee(employeeNumber);

        }

        for (int i = 1; i <= G; i++) {

            qw.sortCompanySummary();
        }
    } catch (IOException io) {
        io.printStackTrace();
    }

}

public void companySummary() {

    System.out.println("Number of companies: " + numberOfCompanies);
    System.out.println("Name of company: "+nameOfCompany);
    System.out.println("Number of employees: "+iE);


}

}

我想在这里做的是动态创建EmployeeRecord类的单独实例。例如

EmployeeRecord qw = new EmployeeRecord();
EmployeeRecord we = new EmployeeRecord();

Answer 1

首先，您需要将目标代码与控制代码分开。

其次，您需要某种集合或数组来保存您的对象。

以下是您的代码外观的概念：

public class UI{ // <---- this class will control the flow of your program
    public static void main(String[] args){
        private List<Company> company; // <---- this Collection object holds many Company objects
        ...
        for(int i=0;i<company.size();i++){
            Company c = new Company();
            c.setName(br.readLine());
            List<Employee> employee = new ArrayList<Employee>();
            ...
            for(int j=0;j<employee.size();j++){
                Employee e = new Employee();
                e.setName(br.readLine());
                ...
                employee.add(e);
            }
            c.setEmployee(employee);
            company.add(c);
         }
    }
}

public class Company{ // <---- this class will represent the companies
    private List<Employee> employee;
    private String name;
    public void setEmployee(List<Employee> employee){
        this.employee = employee;
    }
    ....
}

public class Employee{ // <----- this class will represent the employees
    private String name;
    private int empNo;
    public int getEmpNo(){
        return empNo;
    }
    ...
}

Answer 2

我没有正确理解这个问题，但仔细查看代码，我相信你需要在循环中创建对象，因为你正在从用户那里获取输入。这是您需要做的：

ArrayList<EmployeeRecord> qwList = new ArrayList<EmployeeRecord>();

在要求用户输入之前声明列表。现在在循环内创建对象，为它们分配值并将这些对象添加到列表中。这是您可以在列表中执行的操作

for (int i = 1; i <= G; i++) {

        EmployeeRecord qw = new EmployeeRecord (); 
        System.out.println("Enter name of the company: ");
        String company = br.readLine();
        qw.company(company);
        System.out.println("Enter Number of employees: ");
        String employeeNumber = br.readLine();
        qw.employee(employeeNumber);
        qwList.add(qw);

    }

对于每个公司，已在列表中插入新对象。现在，您可以使用此列表执行任何操作。打印所有记录或对其进行排序。

Answer 3

根据您发布的代码以及您提到的对象的动态创建，我认为唯一的方法是您应该查看Collections Framework。

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