Experiment 6 input / output stream

One 、 The experiment purpose

        master RandomAccessFile The use of the class ; Master character input 、 Output stream and buffered input 、 Use of output streams .

Two 、 Experimental content

         Programming calendar Notepad . The specific requirements are as follows ：

        （1） The calendar can set the date by entering the year and month in the text box , You can also turn around by year , Click... With the left mouse button “ Last year ” and “ Next year ” Button , Subtract one and add one to the year of the current calendar . You can also turn around by month in a certain year , Click... With the left mouse button “ Last month, ” and “ Next month ” Button , Subtract one and add one to the calendar month .

        （2） Left click the date on the calendar , You can use the notepad on the right （ Text area ） Edit relevant logs , And save the log to a file , The name of the file is a sequence of characters consisting of the current date . Users can read 、 Delete the log of a certain date , You can also continue to add new content to a log . In preservation 、 When deleting and reading logs, a confirmation dialog box will pop up first , To confirm saving 、 Delete and read operations .

        （3） When there is a log on a certain date , The date is in bold 16 The number shows , The log shows the date ; When the user deletes the log of a certain date , This date restores the original appearance .

         Achieve the effect diagram （ Reference resources ） as follows ： 

3、 ... and 、 Code implementation

        The design idea is as follows ：

        The page can be divided into four sections ： The up and down or so . The top and bottom layout adopts FlowLayout, Arrange the components from left to right ; Because there are seven rows and seven columns on the left , Each cell is the same size , So we can use GridLayout Layout manager ; On the right is FlowLayout Layout , Arrange from top to bottom . Because the window is divided into four parts up, down, left and right , So the window uses BorderLayout Layout .

// Initialization interface 
    public void init() {
        // Set window size 
        this.setBounds(400, 100, 480, 440);
        this.setLayout(new BorderLayout(10, 15));

        // Up, down, left and right four plates 
        northPanel = new JPanel(new FlowLayout(FlowLayout.LEFT, 15, 10));
        southPanel = new JPanel(new FlowLayout(FlowLayout.CENTER, 10, 10));
        leftPanel = new JPanel(new GridLayout(7, 7));
        rightPanel = new JPanel(new BorderLayout(10, 10));

        // Global Fonts 
        Font font = new Font("Serief", Font.BOLD, 14);

        // Set the upper layout 
        // Year button 
        jtf_year = new JTextField(4);
        jtf_year.setPreferredSize(new Dimension(76, 26));
        jtf_year.setText(String.valueOf(this.year));
        jtf_year.setEditable(false);
        jtf_year.setBackground(Color.white);

        preYear = new JButton(" Last year ");
        preYear.setFont(font);
        nextYear = new JButton(" Next year ");
        nextYear.setFont(font);
        preYear.addActionListener(this);
        nextYear.addActionListener(this);

        // Month button 
        jtf_month = new JTextField(4);
        jtf_month.setText(String.valueOf(this.month));
        jtf_month.setPreferredSize(new Dimension(76, 26));
        jtf_month.setEditable(false);
        jtf_month.setBackground(Color.white);

        nextMonth = new JButton(" Next month ");
        nextMonth.setFont(font);
        preMonth = new JButton(" Last month, ");
        preMonth.setFont(font);
        nextMonth.addActionListener(this);
        preMonth.addActionListener(this);

        // Add these components to the panel 
        northPanel.add(preYear);
        northPanel.add(jtf_year);
        northPanel.add(nextYear);
        northPanel.add(preMonth);
        northPanel.add(jtf_month);
        northPanel.add(nextMonth);


        // Set the layout on the left 
        // Set the head of the calendar 
        String weeks[] = {" Japan ", " One ", " Two ", " 3、 ... and ", " Four ", " 5、 ... and ", " 6、 ... and "};
        JLabel title[] = new JLabel[7];
        for (int i = 0; i < 7; i++) {
            title[i] = new JLabel(weeks[i]);
            title[i].setFont(font);
            title[i].setBorder(BorderFactory.createRaisedBevelBorder());
            leftPanel.add(title[i]);
        }
        // Set the day of the calendar 
        everyDay = new JTextField[42];
        for (int i = 0; i < 42; i++) {
            everyDay[i] = new JTextField();
            everyDay[i].addMouseListener(this);
            everyDay[i].setEditable(false);
            everyDay[i].setBackground(Color.white);
            leftPanel.add(everyDay[i]);
        }

        // Get the daily schedule , Fill in the calendar 
        calendar = new CalendarBean(year, month);
        this.setCalendarDayText();


        // Set the layout on the right 
        // Current date prompt 
        lb_date = new JLabel(" The calendar ：" + year + " year " + month + " month " + day + " Japan ", JLabel.CENTER);
        lb_date.setFont(font);
        // journal 
        note = new JTextArea(14, 20);
        rightPanel.add(lb_date, BorderLayout.NORTH);
        rightPanel.add(new JScrollPane(note), BorderLayout.SOUTH);


        // Set the button layout below 
        btn_save = new JButton(" Save log ");
        btn_delete = new JButton(" Delete log ");
        btn_read = new JButton(" Read log ");

        btn_save.setFont(font);
        btn_delete.setFont(font);
        btn_read.setFont(font);

        btn_save.addActionListener(this);
        btn_delete.addActionListener(this);
        btn_read.addActionListener(this);

        southPanel.add(btn_save);
        southPanel.add(btn_delete);
        southPanel.add(btn_read);

        // Add these panels to the window 
        this.add(leftPanel, BorderLayout.CENTER);
        this.add(rightPanel, BorderLayout.EAST);
        this.add(northPanel, BorderLayout.NORTH);
        this.add(southPanel, BorderLayout.SOUTH);
        this.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
        this.setVisible(true);
    }

// Read and write file operation 
    private void readNote() {
        // Clear the log area first 
        note.setText("");
        String path = "F:/IDEA/workspace/Test6/note/" + year + "" + month + "" + day + ".txt";
        File file = new File(path);
        // If the file exists , Just read the log ; If it doesn't exist, it will prompt 
        if (file.exists()) {
            try {
                BufferedReader br = new BufferedReader(new FileReader(file));
                String line;
                StringBuffer sb = new StringBuffer();
                // Read line by line , Add the characters of each line to the character buffer , Finally, add all the contents to the log area 
                while ((line = br.readLine()) != null) {
                    sb.append(line);
                }
                note.setText(sb.toString());
                br.close();
            } catch (Exception ex) {
                ex.printStackTrace();
            }
        }
    }

    private void deleteNote() {
        String path = "F:/IDEA/workspace/Test6/note/" + year + "" + month + "" + day + ".txt";
        File file = new File(path);
        // There is no log for the current date , You can't delete 
        if (!file.exists()) {
            JOptionPane.showMessageDialog(null, " There is no log for the current date ！", " Tips ", JOptionPane.WARNING_MESSAGE);
            return;
        }
        String msg = " Sure to delete " + year + " year " + month + " month " + day + " Japan " + " Do you have a good log ？";
        int result = JOptionPane.showConfirmDialog(this, msg, " inquiry ",
                JOptionPane.YES_NO_OPTION, JOptionPane.QUESTION_MESSAGE);
        if (result == JOptionPane.YES_OPTION) {
            try {
                // If the file exists , Just delete 
                if (file.exists()) {
                    boolean success = file.delete();
                    if (success) {
                        JOptionPane.showMessageDialog(null, " Delete successful ！", " Delete successful ", JOptionPane.INFORMATION_MESSAGE);
                        note.setText("");
                    } else {
                        JOptionPane.showMessageDialog(null, " Delete failed ！", " Delete failed ", JOptionPane.ERROR_MESSAGE);
                    }
                }
            } catch (Exception ex) {
                ex.printStackTrace();
            }
        }
    }

    private void addNote() {
        // Determine whether there is a document of that date , New if not , Add if necessary 
        String path = "F:/IDEA/workspace/Test6/note/" + year + "" + month + "" + day + ".txt";
        File file = new File(path);
        String msg = "";
        if (file.exists()) {
            msg = year + " year " + month + " month " + day + " Japan " + " There are logs , Add new content to the log ？";
        } else {
            msg = " Sure to save " + year + " year " + month + " month " + day + " Japan " + " Do you have a good log ？";
        }
        String content = note.getText();
        // Tips 
        int result = JOptionPane.showConfirmDialog(this, msg, " inquiry ",
                JOptionPane.YES_NO_OPTION, JOptionPane.QUESTION_MESSAGE);
        // If you choose the yes option , Just save the log 
        if (result == JOptionPane.YES_OPTION) {
            try {
                // If the log file does not exist, you must first create 
                if (!file.exists()) {
                    file.createNewFile();
                }
                // Append the log to the file 
                BufferedWriter bw = new BufferedWriter(new FileWriter(file, true));
                bw.write(content);
                bw.flush();
                bw.close();
                JOptionPane.showMessageDialog(null, " Saved successfully ！", " Saved successfully ", JOptionPane.INFORMATION_MESSAGE);
            } catch (Exception ee) {
                ee.printStackTrace();
            }
        }
    }

// Fill in the number of days 
    private void setCalendarDayText() {
        String days[] = calendar.getCalendar();
        String key = year + "" + month;
        // look for note Under the folder , Log file of current month , See which days there are logs 
        File[] files = new File("F:/IDEA/workspace/Test6/note/").listFiles();
        ArrayList<Integer> list = new ArrayList<>();
        for (int i = 0; i < files.length; i++) {
            String name = files[i].getName();
            if (name.startsWith(key, 0)) {
                int index = name.indexOf(key) + key.length();
                String d = name.split(".txt")[0].substring(index);
                list.add(Integer.parseInt(d));
            }
        }
        for (int i = 0; i < 42; i++) {
            everyDay[i].setText(days[i]);
            everyDay[i].setFont(null);// Clear the original BOLD effect 
            // The day of the log will be displayed in bold 
            if (days[i] != null) {
                if (list.indexOf(Integer.parseInt(days[i])) != -1) {
                    everyDay[i].setFont(new Font("TimesRoman", Font.BOLD, 16));
                }
            }
        }
    }


// Last year 、 Next year 、 Last month, 、 Next month button event handling 
    @Override
    public void actionPerformed(ActionEvent e) {
        try {
            if (e.getSource() == nextYear) {
                year += 1;
                jtf_year.setText(String.valueOf(year));
                calendar.setYear(year);
                this.setCalendarDayText();
            } else if (e.getSource() == preYear) {
                year -= 1;
                jtf_year.setText(String.valueOf(year));
                calendar.setYear(year);
                this.setCalendarDayText();
            } else if (e.getSource() == nextMonth) {
                // If it's not the last month 
                if (month < 12) {
                    month += 1;
                    jtf_month.setText(String.valueOf(month));
                    calendar.setMonth(month);
                    this.setCalendarDayText();
                } else {
                    JOptionPane.showMessageDialog(null, " No next month ！", " Tips ", JOptionPane.WARNING_MESSAGE);
                }
            } else if (e.getSource() == preMonth) {
                if (month > 1) {
                    month -= 1;
                    calendar.setMonth(month);
                    jtf_month.setText(String.valueOf(month));
                    this.setCalendarDayText();
                } else {
                    JOptionPane.showMessageDialog(null, " Not last month ！", " Tips ", JOptionPane.WARNING_MESSAGE);
                }
            } else if (e.getSource() == btn_save) {
                addNote();
            } else if (e.getSource() == btn_read) {
                readNote();
            } else if (e.getSource() == btn_delete) {
                deleteNote();
            }
        } catch (Exception ex) {
            ex.printStackTrace();
        }
    }

import java.util.Calendar;

// Tool class , Used to get the calendar of each month , namely day And weekday Correspondence of 
public class CalendarBean {
    int year, month = 0;

    public CalendarBean(int y, int m) {
        this.year = y;
        this.month = m;
    }

    public void setYear(int y) {
        this.year = y;
    }

    public int getYear() {
        return this.year;
    }

    public void setMonth(int m) {
        this.month = m;
    }

    public int getMonth() {
        return this.month;
    }

    public String[] getCalendar() {
        String days[] = new String[42];
        Calendar date = Calendar.getInstance();
        date.set(year, month - 1, 1);
        int week = date.get(Calendar.DAY_OF_WEEK) - 1;
        int day = 0;

        // Judge the big month 
        if (month == 1 || month == 3 || month == 5 || month == 7
                || month == 8 || month == 10 || month == 12) {
            day = 31;
        }

        // Judge Xiaoyue 
        if (month == 4 || month == 6 || month == 9 || month == 11) {
            day = 30;
        }

        // Judge ordinary and leap years 
        if (month == 2) {
            if (((year % 4 == 0) && (year % 100 != 0)) || (year % 400 == 0)) {
                day = 29;
            } else {
                day = 28;
            }
        }

        for (int i = week, n = 1; i < week + day; i++) {
            days[i] = String.valueOf(n);
            n++;
        }
        return days;
    }
}