java - 我可以使用已添加到 ArrayList 的不同类的方法吗？

Question

我有一个 Project 类，我希望它包含我想做的项目。我是一名珠宝商，基本上想从我正在进行的每个项目中获得一个文件。现在，每个文件都有一个名称、开始日期、截止日期和描述。我想调用 printPro() 我只是不知道如何调用。

项目类如下所示:

public class Project {
    String name;
    int date;//start date
    int fDate;//finish date
    String description;

    public Project(String gName, int gDate, int gFDate, String gDescription){
        // mean they are the ones that are given.
    }
    public void receivedName(String receivedName) {
        name= receivedName;
    }
    public void receivedDate(int receivedDate) {
    date= receivedDate;
    }
    public void receivedFDate(int receivedDate) {
    fDate= receivedDate;
    }


    public String returnName(){
    return name;
    }
    public int returnDate(){
    return date;
    }
    public int returnFDate(){
    return fDate;
    }
    public String returnDescription(){
    return description;
    }

    public String printPro(int index){
    String tempString = ("Project Name: " + name + 
            "\nStart Date: " + date +
            "\nFinish Date: " + fDate + "\nDescription: " +     description);
        return tempString;
    }

    public void printProject(int index){

    System.out.println("Project Name: " + name + 
            "\nStart Date: " + date +
            "\nFinish Date: " + fDate + "\nDescription: " +     description);
        }

    }

现在我所拥有的只是通过控制台运行的一切。当我学习如何创建和导入文本文件时，我打算稍后构建一个窗口。不管怎样，这里是控制台的代码:

public class Top{
    Math help = new Math();//Creates a Math object
    People person = new People();//Creates a People object
//  Project nProject= new Project(); 
    ArrayList<Project> mProject = new ArrayList<Project>();
    Project[] storeProject; //Tried to create an array of Projects I could just add to. 
    Project[] storeTempProject;
    StringTest sTest = new StringTest(); // This is my class to use the console.
    String choice; //Temporary strings
    String redo;

public static void main (String [] args){
//  ============Project Menu =========================
private void project() {
    System.out.println("ADD, DELETE, REVIEW, or BACK?");
    sTest.stringReader();
    choice = sTest.getString();

    if (sTest.test(choice, "add")){
        System.out.println("What would you like to call this project?");    
        sTest.stringReader();
        String name = sTest.getString();

        System.out.println("When would you like it to start?");
        sTest.stringReader();
        String startDate = sTest.getString();
        int sDate = Integer.parseInt(startDate);

        System.out.println("When would you like it to end?");
        sTest.stringReader();
        String finishDate = sTest.getString();
        int fDate = Integer.parseInt(finishDate);

        System.out.println("What is the description of your project?");
        sTest.stringReader();
        String projectDescription = sTest.getString();

        mProject.add(new Project(name, sDate, fDate, projectDescription));
    }
}

我从我的代码中删除了一些不必要的东西，所以它不会让这个问题陷入困境。如果您需要更多信息，请告诉我。我已经搜索了一个小时，所以我假设这行不通，我需要换一种方式。

Answer 1

我不完全确定你的问题，但也许这就是你所追求的:

您可以像这样在 ArrayList 的元素上调用方法:

for (Project proj : mProject) {
    proj.printPro();
}

要显示第一个，只需执行以下操作:

mProject.get(0) 

将返回 ArrayList 中的第一个项目。要返回第二个，只需将“get”的参数更改为 1。您应该能够弄清楚如何获取其余部分。