java - 从另一个类调用方法并检索其结果 (Java)

Question

我有 2 个类(IterativeVsRecursive 和 Sequence)，Sequence 类执行数学操作并将值返回给 IterativeVsRecursive，或者至少这是目的。

我相信我错过了一些简单的事情，但对如何完成这项工作感到困惑。

迭代与递归类:

import java.awt.GridLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

import javax.sound.midi.Sequence;
import javax.swing.ButtonGroup;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JRadioButton;
import javax.swing.JTextField;

public class IterativeVsRecursiveGUI extends JFrame implements ActionListener {
    private JLabel radioButton1Label = new JLabel();
    private JLabel radioButton2Label = new JLabel();
    private JLabel inputLabel = new JLabel();
    private JLabel resultLabel = new JLabel();
    private JLabel efficiencyLabel = new JLabel();
    private JLabel computeButtonLabel = new JLabel();
    private ButtonGroup radioButtonGroup = new ButtonGroup();
    private JRadioButton radioButtonIterative = new JRadioButton("Iterative");
    private JRadioButton radioButtonRecursive = new JRadioButton("Recursive");
    private JTextField inputField = new JTextField();
    private JTextField resultField = new JTextField();
    private JTextField efficiencyField = new JTextField();
    private JButton computeButton = new JButton();
    private int efficiencyCounter;

    public IterativeVsRecursiveGUI()

    {
        super("Project 3");
        setSize(300, 200);
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        getContentPane().setLayout(new GridLayout(6, 2));
        radioButtonGroup.add(radioButtonIterative);
        radioButtonIterative.setSelected(true);
        // radioButtonIterative.setText("Iterative");
        getContentPane().add(radioButtonIterative);
        radioButtonGroup.add(radioButtonRecursive);
        // radioButtonRecursive.setText("Recursive");
        getContentPane().add(radioButtonRecursive);
        inputLabel.setText("Enter number: ");
        getContentPane().add(inputLabel);
        getContentPane().add(inputField);
        computeButton.setText("Compute");
        computeButton.addActionListener(this);
        getContentPane().add(computeButton);
        resultLabel.setText("Result: ");
        getContentPane().add(resultLabel);
        getContentPane().add(resultLabel);
        resultField.setEditable(false);
        efficiencyLabel.setText("Efficiency: ");
        getContentPane().add(efficiencyLabel);
        getContentPane().add(efficiencyField);
        efficiencyField.setEditable(false);
        pack();
    }

    @Override
    public void actionPerformed(ActionEvent button) {
        int result;
        efficiencyCounter = 0;
        if (radioButtonIterative.isSelected()) {
            result = Sequence.computeIterative(Integer.parseInt(inputField.getText()));
        } else {
            result = Sequence.computeRecursive(Integer.parseInt(inputField.getText()));
        }
        resultField.setText(Integer.toString(result));
        efficiencyField.setText(Integer.toString(efficiencyCounter));
    }

    public static void main(String[] args) {
        IterativeVsRecursiveGUI IterativeVsRecursiveGUI = new IterativeVsRecursiveGUI();
        IterativeVsRecursiveGUI.setVisible(true);
    }
}

序列类:

public class Sequence {
    private int efficiencyCounter = 0;

    public int computeIterative(int input) {
        int answer = 0;
        if (input == 0) {
            efficiencyCounter++;
            answer = 0;
        } else if (input == 1) {
            efficiencyCounter++;
            answer = 1;
        } else {
            efficiencyCounter++;
            int firstTerm = 0;
            int secondTerm = 1;
            for (int i = 2; i <= input; i++) {
                answer = (3 * secondTerm) - (2 * firstTerm);
                firstTerm = secondTerm;
                secondTerm = answer;
            }
        }
        return answer;
    }

    public int computeRecursive(int input) {
        int answer = 0;
        efficiencyCounter++;
        if (input == 0) {
            answer = 0;
        } else if (input == 1) {
            answer = 1;
        } else {
            answer = (3 * computeRecursive(input - 1)) - (2 * computeRecursive(input - 2));
        }
        return answer;
    }
}

目的是拥有一个显示 Sequence 类结果的 GUI。

Answer 1

I should have been clear in that it is not allowing me to call the non-static methods in Sequence, but if I make them static, by adding "void", then the computeRecursive method throws an errror saying that 'void' type not allowed here

或者，由于该方法已经是实例方法，因此创建 Sequence 的实例

@Override
public void actionPerformed(ActionEvent button) {
    int result;
    efficiencyCounter = 0;

    Sequence sequence = new Sequence();
    if (radioButtonIterative.isSelected()) {
        result = sequence.computeIterative(Integer.parseInt(inputField.getText()));
    } else {
        result = sequence.computeRecursive(Integer.parseInt(inputField.getText()));
    }
    resultField.setText(Integer.toString(result));
    efficiencyField.setText(Integer.toString(efficiencyCounter));
}