# 2019-12-16 上課範例

[TOC]

## Student.java

/**
 * 學生類別
 * 
 * @author kChen
 * @version 0.1.0
 *
 */
public class Student {

	/**
	 * 學生學號
	 */
	private String id;

	/**
	 * 學生姓名
	 */
	private String name;

	
	/**
	 * 學生的中文成績
	 */
	private int chinese;

	/**
	 * 學生的英文成績
	 */
	private int english;

	/**
	 * 學生的數學成績
	 */
	private int math;

	/**
	 * 建構子，預設學生資料
	 */
	public Student() {
		name = "老王";
		id = "S01";
		chinese = 95;
		english = 60;
		math = 78;
	}

	/**
	 * 自行輸入資料的建構子
	 * 
	 * @param id      學生學號
	 * @param name    學生姓名
	 * @param chinese 中文成績
	 * @param english 英文成績
	 * @param math    數學成績
	 */
	public Student(String id, String name,  int chinese, int english, int math) {
		this.id = id;
		this.name = name;
		this.chinese = chinese;
		this.english = english;
		this.math = math;
	}

	/**
	 * 計算學生各科的總合
	 * 
	 * @return 學生各科的總合
	 */
	public int sum() {
		return this.chinese + this.english + this.math;
	}

	/**
	 * 計算學生各科的平均
	 * 
	 * @return 學生的各科的平均
	 */
	public double avg() {
		return this.sum() / 3.0;
	}

	@Override
	public String toString() {
		String str = this.id+ ","; 
		str += this.name + ",";
		str += this.chinese + ",";
		str += this.english + ",";
		str += this.math + ",";
		str += this.sum() + ",";
		str += this.avg();
		return str;
	}
}

## StudentDabase.java

import java.awt.EventQueue;

import javax.swing.JFrame;
import javax.swing.JTextField;
import java.awt.Font;
import javax.swing.JLabel;
import javax.swing.SwingConstants;
import javax.swing.JButton;
import javax.swing.JTextArea;
import java.awt.event.ActionListener;
import java.util.ArrayList;
import java.awt.event.ActionEvent;

public class StudentDatabase {

	// 我們自己宣告的Feild
	private ArrayList<Student> studentList;
	
	// WindowBuilder 宣告的
	private JFrame frame;
	private JTextField txtName;
	private JTextField txtStudentID;
	private JTextField txtChinese;
	private JTextField txtEnglish;
	private JTextField txtMath;
	private JTextArea txtrOutput;

	/**
	 * Launch the application.
	 */
	public static void main(String[] args) {
		EventQueue.invokeLater(new Runnable() {
			public void run() {
				try {
					StudentDatabase window = new StudentDatabase();
					window.frame.setVisible(true);
				} catch (Exception e) {
					e.printStackTrace();
				}
			}
		});
	}

	/**
	 * Create the application.
	 */
	public StudentDatabase() {
		// WindowBuilder 初始化
		initialize();

		// 我們自己的初始化
		this.studentList = new ArrayList<Student>();
	}

	/**
	 * Initialize the contents of the frame.
	 */
	private void initialize() {
		frame = new JFrame();
		frame.setTitle("學生資料庫");
		frame.setBounds(100, 100, 660, 469);
		frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
		frame.getContentPane().setLayout(null);

		txtName = new JTextField();
		txtName.setFont(new Font("微軟正黑體", Font.PLAIN, 18));
		txtName.setText("張三");
		txtName.setBounds(99, 71, 108, 30);
		frame.getContentPane().add(txtName);
		txtName.setColumns(10);

		JLabel lblName = new JLabel("姓名");
		lblName.setHorizontalAlignment(SwingConstants.RIGHT);
		lblName.setFont(new Font("微軟正黑體", Font.PLAIN, 18));
		lblName.setBounds(40, 74, 49, 25);
		frame.getContentPane().add(lblName);

		JLabel lblStudentID = new JLabel("學號");
		lblStudentID.setHorizontalAlignment(SwingConstants.RIGHT);
		lblStudentID.setFont(new Font("微軟正黑體", Font.PLAIN, 18));
		lblStudentID.setBounds(40, 29, 49, 25);
		frame.getContentPane().add(lblStudentID);

		txtStudentID = new JTextField();
		txtStudentID.setText("S01");
		txtStudentID.setFont(new Font("微軟正黑體", Font.PLAIN, 18));
		txtStudentID.setColumns(10);
		txtStudentID.setBounds(99, 26, 108, 30);
		frame.getContentPane().add(txtStudentID);

		txtChinese = new JTextField();
		txtChinese.setText("76");
		txtChinese.setFont(new Font("微軟正黑體", Font.PLAIN, 18));
		txtChinese.setColumns(10);
		txtChinese.setBounds(289, 26, 108, 30);
		frame.getContentPane().add(txtChinese);

		JLabel lblChinese = new JLabel("中文");
		lblChinese.setHorizontalAlignment(SwingConstants.RIGHT);
		lblChinese.setFont(new Font("微軟正黑體", Font.PLAIN, 18));
		lblChinese.setBounds(225, 29, 49, 25);
		frame.getContentPane().add(lblChinese);

		JLabel lblEnglish = new JLabel("英文");
		lblEnglish.setHorizontalAlignment(SwingConstants.RIGHT);
		lblEnglish.setFont(new Font("微軟正黑體", Font.PLAIN, 18));
		lblEnglish.setBounds(225, 74, 49, 25);
		frame.getContentPane().add(lblEnglish);

		txtEnglish = new JTextField();
		txtEnglish.setText("80");
		txtEnglish.setFont(new Font("微軟正黑體", Font.PLAIN, 18));
		txtEnglish.setColumns(10);
		txtEnglish.setBounds(289, 71, 108, 30);
		frame.getContentPane().add(txtEnglish);

		JLabel lblMath = new JLabel("數學 ");
		lblMath.setHorizontalAlignment(SwingConstants.RIGHT);
		lblMath.setFont(new Font("微軟正黑體", Font.PLAIN, 18));
		lblMath.setBounds(435, 29, 49, 25);
		frame.getContentPane().add(lblMath);

		txtMath = new JTextField();
		txtMath.setText("66");
		txtMath.setFont(new Font("微軟正黑體", Font.PLAIN, 18));
		txtMath.setColumns(10);
		txtMath.setBounds(493, 26, 108, 30);
		frame.getContentPane().add(txtMath);

		JButton btnAdd = new JButton("新增");
		btnAdd.addActionListener(new ActionListener() {
			public void actionPerformed(ActionEvent e) {
				AddClick();
			}
		});
		btnAdd.setFont(new Font("微軟正黑體", Font.PLAIN, 18));
		btnAdd.setBounds(514, 74, 87, 25);
		frame.getContentPane().add(btnAdd);

		txtrOutput = new JTextArea();
		txtrOutput.setFont(new Font("微軟正黑體", Font.PLAIN, 18));
		txtrOutput.setBounds(44, 141, 558, 256);
		frame.getContentPane().add(txtrOutput);
	}

	protected void AddClick() {
		// 取得視窗資料

		String id = this.txtStudentID.getText();
		String name = this.txtName.getText();
		String strChinese = this.txtChinese.getText();
		String strEnglish = this.txtEnglish.getText();
		String strMath = this.txtMath.getText();

		// 將字串轉換成數值
		int chinese = Integer.parseInt(strChinese);
		int english = Integer.parseInt(strEnglish);
		int math = Integer.parseInt(strMath);

		// 產生學生物件
		Student st = new Student(id, name, chinese, english, math);

		// 將學生物件加入至 ArrayList
		this.studentList.add(st);
		int n = this.studentList.size();

		// 將 studentList 顯示至畫面
		String strStudentList = "";
		for (int i = 0; i < n; i++) {
			strStudentList += this.studentList.get(i)+"\n";
		}

		this.txtrOutput.setText(strStudentList);
	}
}

## StudentList.java

import java.util.ArrayList;

/**
 * 學生清單類別
 * @author kChen
 * @version 0.0.1
 * @since 2019/12/16
 *
 */
public class StudentList {

	private ArrayList<Student> studentList;
	
	/**
	 * 建構子
	 */
	public StudentList() {
		studentList = new ArrayList<Student>();
	}

	/**
	 * 插入學生資料在第 index 筆
	 * @param index 一個int數字，為插入學生資料的編號
	 * @param element 一個Student，為欲插入的學生資料
	 */
	public void add​(int index, Student element) {
		studentList.add(index, element);
	}

	/**
	 * 新增學生資料
	 * @param e 一個Student類別，為欲新增的學生資料
	 * @return
	 */
	public boolean add​(Student e) {
		return studentList.add(e);
	}
	
	
	public void clear() {
		studentList.clear();
	}
	
	/**
	 * 取得第index的學生資料
	 * @param index 一個int，為要讀取的學生編號
	 * @return
	 */
	public Student get​(int index) {
		return studentList.get(index);
	}
	
	/**
	 * 移除第 index 的學生資料
	 * @param index 一個int，為要移除的學生編號
	 * @return
	 */
	public Student remove​(int index) {
		return studentList.remove(index);
	}
	
	public int size() {
		return studentList.size();
	}
	
	/**
	 * 覆寫 toString() 改成學生清單
	 */
	@Override
	public String toString() {
		// 將 studentList 顯示至畫面
		String strStudentList = "";
		for (int i = 0; i < this.studentList.size(); i++) {
			strStudentList += this.studentList.get(i)+"\n";
		}
		return strStudentList;
	}
}

## StudentDatabase2.java

import java.awt.EventQueue;

import javax.swing.JFrame;
import javax.swing.JTextField;
import java.awt.Font;
import javax.swing.JLabel;
import javax.swing.SwingConstants;
import javax.swing.JButton;
import javax.swing.JTextArea;
import java.awt.event.ActionListener;
import java.util.ArrayList;
import java.awt.event.ActionEvent;

public class StudentDatabase2 {

	// 我們自己宣告的Feild
	private StudentList studentList;
	
	// WindowBuilder 宣告的
	private JFrame frame;
	private JTextField txtName;
	private JTextField txtStudentID;
	private JTextField txtChinese;
	private JTextField txtEnglish;
	private JTextField txtMath;
	private JTextArea txtrOutput;

	/**
	 * Launch the application.
	 */
	public static void main(String[] args) {
		EventQueue.invokeLater(new Runnable() {
			public void run() {
				try {
					StudentDatabase2 window = new StudentDatabase2();
					window.frame.setVisible(true);
				} catch (Exception e) {
					e.printStackTrace();
				}
			}
		});
	}

	/**
	 * Create the application.
	 */
	public StudentDatabase2() {
		// WindowBuilder 初始化
		initialize();

		// 我們自己的初始化
		this.studentList = new StudentList();
	}

	/**
	 * Initialize the contents of the frame.
	 */
	private void initialize() {
		frame = new JFrame();
		frame.setTitle("學生資料庫");
		frame.setBounds(100, 100, 660, 469);
		frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
		frame.getContentPane().setLayout(null);

		txtName = new JTextField();
		txtName.setFont(new Font("微軟正黑體", Font.PLAIN, 18));
		txtName.setText("張三");
		txtName.setBounds(99, 71, 108, 30);
		frame.getContentPane().add(txtName);
		txtName.setColumns(10);

		JLabel lblName = new JLabel("姓名");
		lblName.setHorizontalAlignment(SwingConstants.RIGHT);
		lblName.setFont(new Font("微軟正黑體", Font.PLAIN, 18));
		lblName.setBounds(40, 74, 49, 25);
		frame.getContentPane().add(lblName);

		JLabel lblStudentID = new JLabel("學號");
		lblStudentID.setHorizontalAlignment(SwingConstants.RIGHT);
		lblStudentID.setFont(new Font("微軟正黑體", Font.PLAIN, 18));
		lblStudentID.setBounds(40, 29, 49, 25);
		frame.getContentPane().add(lblStudentID);

		txtStudentID = new JTextField();
		txtStudentID.setText("S01");
		txtStudentID.setFont(new Font("微軟正黑體", Font.PLAIN, 18));
		txtStudentID.setColumns(10);
		txtStudentID.setBounds(99, 26, 108, 30);
		frame.getContentPane().add(txtStudentID);

		txtChinese = new JTextField();
		txtChinese.setText("76");
		txtChinese.setFont(new Font("微軟正黑體", Font.PLAIN, 18));
		txtChinese.setColumns(10);
		txtChinese.setBounds(289, 26, 108, 30);
		frame.getContentPane().add(txtChinese);

		JLabel lblChinese = new JLabel("中文");
		lblChinese.setHorizontalAlignment(SwingConstants.RIGHT);
		lblChinese.setFont(new Font("微軟正黑體", Font.PLAIN, 18));
		lblChinese.setBounds(225, 29, 49, 25);
		frame.getContentPane().add(lblChinese);

		JLabel lblEnglish = new JLabel("英文");
		lblEnglish.setHorizontalAlignment(SwingConstants.RIGHT);
		lblEnglish.setFont(new Font("微軟正黑體", Font.PLAIN, 18));
		lblEnglish.setBounds(225, 74, 49, 25);
		frame.getContentPane().add(lblEnglish);

		txtEnglish = new JTextField();
		txtEnglish.setText("80");
		txtEnglish.setFont(new Font("微軟正黑體", Font.PLAIN, 18));
		txtEnglish.setColumns(10);
		txtEnglish.setBounds(289, 71, 108, 30);
		frame.getContentPane().add(txtEnglish);

		JLabel lblMath = new JLabel("數學 ");
		lblMath.setHorizontalAlignment(SwingConstants.RIGHT);
		lblMath.setFont(new Font("微軟正黑體", Font.PLAIN, 18));
		lblMath.setBounds(435, 29, 49, 25);
		frame.getContentPane().add(lblMath);

		txtMath = new JTextField();
		txtMath.setText("66");
		txtMath.setFont(new Font("微軟正黑體", Font.PLAIN, 18));
		txtMath.setColumns(10);
		txtMath.setBounds(493, 26, 108, 30);
		frame.getContentPane().add(txtMath);

		JButton btnAdd = new JButton("新增");
		btnAdd.addActionListener(new ActionListener() {
			public void actionPerformed(ActionEvent e) {
				AddClick();
			}
		});
		btnAdd.setFont(new Font("微軟正黑體", Font.PLAIN, 18));
		btnAdd.setBounds(514, 74, 87, 25);
		frame.getContentPane().add(btnAdd);

		txtrOutput = new JTextArea();
		txtrOutput.setFont(new Font("微軟正黑體", Font.PLAIN, 18));
		txtrOutput.setBounds(44, 141, 558, 256);
		frame.getContentPane().add(txtrOutput);
	}

	protected void AddClick() {
		// 取得視窗資料

		String id = this.txtStudentID.getText();
		String name = this.txtName.getText();
		String strChinese = this.txtChinese.getText();
		String strEnglish = this.txtEnglish.getText();
		String strMath = this.txtMath.getText();

		// 將字串轉換成數值
		int chinese = Integer.parseInt(strChinese);
		int english = Integer.parseInt(strEnglish);
		int math = Integer.parseInt(strMath);

		// 產生學生物件
		Student st = new Student(id, name, chinese, english, math);

		// 將學生物件加入至 StudentList
		this.studentList.add​(st);

		// 將 studentList 顯示至畫面
		this.txtrOutput.setText(studentList.toString());
	}
}

###### tags: `Java計算機程式設計` `108-1`