向arrayList Java添加数据

Question

所以我创建了一个日志程序，用户在其中输入KM并保存它，等等

我考虑了四个变量——开始公里数、结束公里数、开始和结束位置。我是java新手，所以我想知道是否有人可以确认是否有更好的方法来做到这一点。这是我到目前为止的代码，我想将其保存到一个排序数组（列表？？）所以我可以访问每个对象，比如startKM，但它们需要在同一行上，就像数组中的对象1一样，然后写入文件

我想做的是将链接列表保存到一个文件中，并添加一个；在toString方法中，以及在读取文件时，在；有更好的方法吗？？谢谢大家。数据是根据用户在文本字段中输入的内容分配的

double startKM;
double endKM;
String startLocation;
String endLocation;


startKM = Double.parseDouble(txtStartKM.getText());
endKM = Double.parseDouble(txtEndKM.getText());

startLocation = txtStartLocation.getText();
endLocation = txtEndLocation.getText();

details.startKM = startKM;
details.endKM = endKM;
details.startLocation = startLocation;
details.endLocation = endLocation;

//List<DrivingDetails> detailsList = new ArrayList<DrivingDetails>();
List detailsList = new ArrayList();

detailsList.add(details);

System.out.println("LinkedList contains = \t " + detailsList.toString());

编辑：我有另一个类（DrivingDetails），它包含以下变量：

public class DrivingDetails {

   double startKM;
   double endKM;
   String startLocation;
   String endLocation;
}

Answer 1

DrivingDetails类违反了面向对象类的封装原则。我会为所有属性添加setter和getter。此外，还可以创建一个contstructor来为您处理初始化

public class DrivingDetails {

    private double startKM;
    private double endKM;
    private String startLocation;
    private String endLocation;

    public DrivingDetails(double startKM, double endKM, String startLocation, String endLocation) {
        this.startKM = startKM;
        this.endKM = endKM;
        this.startLocation = startLocation;
        this.endLocation = endLocation;
    }

    public double getStartKM() {
        return startKM;
    }
    public void setStartKM(double startKM) {
        this.startKM = startKM;
    }

    // rest of the methods left for you ...
}

生成的代码如下所示：

double startKM;
double endKM;
try {
    startKM = Double.parseDouble(txtStartKM.getText());
    endKM = Double.parseDouble(txtEndKM.getText());
} catch (NumberFormatException e | NullPointerException e) {
    // the line above assumes java 7
    // recover
}

DrivingDetails details = new DrivingDetails(startKM, endKM,
        txtStartLocation.getText(),
        txtEndLocation.getText());

List<DrivingDetails> detailsList = new ArrayList<DrivingDetails>();
detailsList.add(details);

希望有帮助