您如何将值加载到JTable中，以便在打开表单时显示以前的值？

Question

如何将数组值加载到JTable这样的格式中，以便每当打开窗体时，它就会显示表的先前值？我不想将表单连接到任何数据库。

到目前为止，这是我的代码，它允许我在文本字段中输入文本，当我单击“创建客户”按钮时，它将值存储到中JTable。但是，如果我退出并重新打开表单，表中以前的数据将消失。我已经做过一些研究，但似乎将netbeans 连接到数据库是保存和检索数据的唯一方法。但是，我相信也可以将数据存储到数组中，但是我不知道如何将数组中的值带入表中。

我需要一些帮助。这是我的学校项目。仅供参考，我使用了一些符号：rbtn = radiobutton, tb = textfields, lbl = label

public class Customer extends javax.swing.JFrame {
String gender;
int year = Calendar.getInstance().get(Calendar.YEAR);
int month = Calendar.getInstance().get(Calendar.MONTH);
int day = Calendar.getInstance().get(Calendar.DAY_OF_MONTH);

int m=10; //array memory size

String[] name = new String[m];
String[] age = new String[m];
String[] genderm = new String [m];
String[] id = new String [m];
String[] mobile = new String [m];
String[] email = new String [m];
String[] address = new String [m];
String[] date = new String [m];
String[] photo = new String[m];

public Customer() {
    initComponents();
    tbdate.setText(day+"/"+(month+1)+"/"+year);
    lblphoto.setIcon(null);              
}

private void btncreateActionPerformed(java.awt.event.ActionEvent  evt)      {                                          
    // TODO add your handling code here:
    if (rbtnmale.isSelected()){
        gender = "Male";
    }
    else if (rbtnfemale.isSelected()){
        gender = "Female";
    }
    DefaultTableModel model = (DefaultTableModel) jtablecustinfo.getModel();
    model.addRow(new Object[]{tbname.getText(),tbage.getText(),gender,tbid.getText(),tbmobile.getText(),tbemail.getText(),tbaddress.getText(),tbdate.getText(),lblphoto.getIcon()});

    for(int i=0;i<m;i++){
    name[i]=tbname.getText();
    age[i] = tbage.getText();
    genderm[i]=gender;
    id[i]=tbid.getText();
    mobile[i]=tbmobile.getText();
    email[i]=tbemail.getText();
    address[i]=tbaddress.getText();
    date[i]=tbdate.getText();
    photo[i]= tbimage.getText();;
    }

    //Reset everything after creation
    JOptionPane.showMessageDialog(null,"Successfully Created Customer");
    tbname.setText("");
    tbage.setText("");
    tbid.setText("");
    tbmobile.setText("");
    tbemail.setText("");
    tbaddress.setText("");
    tbdate.setText("");
    rbtnmale.setSelected(false);
    rbtnfemale.setSelected(false);
    tbdate.setText(day+"/"+(month+1)+"/"+year);
    gender = "";
    tbimage.setText("");
    lblphoto.setText("          -Import photo-");
    lblphoto.setIcon(null);
}

I have included the main points of my code, hope it is sufficient to view!

Answer 1

对于少量数据，请考虑
java.util.prefs.Preferences.

您能为我提供一些使用示例吗？

Several examples are examined in the Preferences API
Overview

and the example cited here
(API and
code).
Alternatively, consider javax.jnlp.PersistenceService, cited
here, “for applications that are
running in the restricted execution environment.”

这个最小的示例通过将先前保存的值添加到表中并覆盖表模型的setValueAt()实现以保存任何更改来更新单个单元格。编辑表，退出并重新启动以查看效果。

package org.name.table;

import java.awt.Dimension;
import java.awt.EventQueue;
import java.util.prefs.Preferences;
import javax.swing.JFrame;
import javax.swing.JScrollPane;
import javax.swing.JTable;
import javax.swing.table.DefaultTableModel;

/**
 * @see https://stackoverflow.com/a/34616583/230513
 */
public class TablePreference {

    private void display() {
        JFrame f = new JFrame("TablePreference");
        f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        f.add(new JScrollPane(new JTable(new PrefModel()) {

            @Override
            public Dimension getPreferredScrollableViewportSize() {
                return new Dimension(128, 32);
            }
        }));
        f.pack();
        f.setLocationRelativeTo(null);
        f.setVisible(true);
    }

    private static class PrefModel extends DefaultTableModel {

        private static final int DEFAULT = 42;
        private static final String VALUE_NAME = "value";
        private final Preferences p = Preferences.userNodeForPackage(TablePreference.class);

        public PrefModel() {
            addColumn("A");
            addRow(new Object[]{p.getInt(VALUE_NAME, DEFAULT)});
        }

        @Override
        public void setValueAt(Object aValue, int row, int col) {
            super.setValueAt(aValue, row, col);
            p.putInt(VALUE_NAME, (int) aValue);
        }

        @Override
        public Class<?> getColumnClass(int col) {
            return getValueAt(0, col).getClass();
        }
    }

    public static void main(String[] args) {
        EventQueue.invokeLater(new TablePreference()::display);
    }
}