JTable 单元格更改上的 JAVA 更新数据库

Question

我对 Java 很菜鸟(这不是什么新鲜事)，而且我找不到一个好的教程。我使用 jTable 来显示一个表，其中填充了 MySQL 数据库中的数据。

到目前为止一切顺利，我得到了 table :

标准，您可以单击表格单元格，它会更改为可以填充新内容的文本字段。你们都知道这一点，但我如何使用它来更新数据库中的值？

我的代码:

import [...];
public class table extends JPanel {
    public String table;
    private Database db;

    public table(String tablename, Database db){

        try {
            table = tablename;
            this.db = db;

            //Get table with and height
            ResultSet res = db.query("SELECT COUNT( * ) FROM `"+table+"`");
            ResultSet res2 = db.query("SELECT COUNT( * ) FROM INFORMATION_SCHEMA.COLUMNS WHERE table_name = '"+table+"'");

            int rows = 0;
            int collums = 0;

            res.next();
            res2.next();

            rows = res.getInt(1);
            collums = res2.getInt(1);

            //Get table column names and set then in array
            ResultSet clom = db.query("DESCRIBE  `"+table+"`");

            String[] columnNames = new String[collums];

            int s = 0;

            while(clom.next()){
                columnNames[s] = clom.getString(1);
                s++;
            }

            //get table data and put in array
            Object[][] data = new Object[rows][collums];

            ResultSet result = db.query("SELECT * FROM `"+table+"`");

            int q = 0;

            while(result.next()){
                for(int a=0; a<= (collums - 1); a++){
                    data[q][a] = result.getString(a + 1);
                    //System.out.println(q + " - " + a);
                }
                q++;
            }

            //Make Jtable of the db result form the two array's
            final JTable table = new JTable(data, columnNames);
            table.setPreferredScrollableViewportSize(new Dimension(500, 70));
            table.setFillsViewportHeight(true);

            // do some event listening for cell change

            JScrollPane scrollPane = new JScrollPane(table);
            JFrame frame = new JFrame("table editor");
            scrollPane.setOpaque(true);
            frame.setContentPane(scrollPane);
            frame.pack();
            frame.setSize(600, 800);
            frame.setVisible(true);
        } catch (SQLException e1) {
            e1.printStackTrace();
        }
    }
}

我想我需要绑定(bind)某种表监听器，当某些内容发生变化时，我会获取表中的所有值并使用查询更新它们。

我该怎么做？

这是我的伪代码:

table.bindCellEventListner(callback(t){
     Array row = t.getAllValuesAsArrayOfRow();

     String data = "";

     int f = 0
     while(row.next()){
         data .= "`"+clom[f]+"` = '"+row[f]+"',"
         f++;
     }
     data.delLastChar();
     db.query("UPDATE `"+table+"` SET "+data+" WHERE `id` ="+row[0]+";");

});

Answer 1

删除的答案抄袭了 Rachel Swailes 14 年前的答案，发现 here 。为了完整起见，并且因为答案正确且有用，我在此处引用了相关文字:

Step 1: It's going to be way easier for the whole thing if you make your table extend a TableModel from now (if you haven't already). So if you need help with that just ask.

Step 2: In the table model you need to enable the cells to be editable. In the TableModel class that you make, you need to add these methods

public boolean isCellEditable(int row, int col) { 
  return true; 
}

public void setValueAt(Object value, int row, int col) {
  rowData[row][col] = value;
  fireTableCellUpdated(row, col);
}

Step 3: You will see in the second method that we fire a method called fireTableCellUpdated. So here we can catch what the use it changing. You need to add a TableModelListener to your table to catch this.

mytable.getModel().addTableModelListener(yourClass);

And in the class that you decide will implement the TableModelListener you need this

public void tableChanged(TableModelEvent e) {
  int row = e.getFirstRow();
  int column = e.getColumn();
  TableModel model = (TableModel)e.getSource();
  Object data = model.getValueAt(row, column);
  ...
}

now you have the data in the cell and the place in the grid where the

cell is so you can use the data as you want