JAva获取类变量：多个方法或一个带开关的方法

Question

Is there a best practice regarding the two options below to get variables from, in this case, the MainScene class ? I actually have many more variables to get so I would end up with many other methods or 2-3 switch methods.

class MainScene

Option 1 - Multiple Methods

public TextField getLoadTxt(){
    return loadTxt;
}

public TextField getdownTxt(){
    return downTxt;
}

public TextField getflightTxt(){
    return flightTxt;
}

public TextField getacTxt(){
    return acTxt;
}

public TextField getairportTxt(){
    return airportTxt;
}

Option 2 - One Method with Switch

public TextField getTextField(String textField){
    TextField text = new TextField();
    text.setText("Default");
    switch(textField){
        case "loadTxt": return loadTxt;
        case "downTxt": return downTxt;
        case "flightTxt": return flightTxt;
        case "acTxt": return acTxt;
        case "airportTxt": return airportTxt;
        default: return text;
    }
}

Answer 1

For the option 1, you can use lombok, which helps generate all the getter functions. For the option 2, you can use reflection.

If using Maven, including

<dependency>
    <groupId>org.projectlombok</groupId>
    <artifactId>lombok</artifactId>
    <version>1.14.8</version>
</dependency>

and here's the code:

import lombok.Data;
public @Data
class ReflectionTest {
    String str = "abc";

    String str2 = "ecd";

    public void get() {
        try {
            System.out.println(this.getClass().getDeclaredField("str").get(this));
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}

public class App {
    public static void main(String[] args) {
        ReflectionTest reflectionTest = new ReflectionTest();
        // get value by option 2
        reflectionTest.get();
        // get value by option 1
        System.out.println(reflectionTest.getStr2());
    }
}

Answer 2

Usually Option 1, and most (all?) IDE can auto-generate setters/getter methods.

Also, if you let an IDE do all the work, easier and less chances of introduced bugs.

Answer 3

In general you should have one 'getter' method for each variable. However if you have a larger number of variables that represent different attributes of the same type then you might want to consider using an attribute enumeration:

public enum Field {
    LOAD, DOWN, FLIGHT, AC, AIRPORT;
}

public MainScene {
    private final EnumMap<Field,TextField> fields = new EnumMap<>(Field.class);

    public TextField getField(Field field) {
        return fields.get(field);
    }
}