tablebuilderframe.java

用java编写的数据库管理程序

package createdb;

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import javax.swing.event.*;

/**
* TableBuilderFrame: a display which builds SQL CREATE statements
* <p/>
* TableBuilder, which extends JTable, is a key component.
*/
class TableBuilderFrame extends JInternalFrame{

  protected int nRows = 15;
  protected int nColumns = 6;
  protected JTable table;
  protected JTextArea SQLPane = new JTextArea();
  protected JButton createButton = new JButton("Create Table");
  protected ActionListener commandListener = null;

  protected String tableName = null;
  protected String SQLCommand = "";
  protected String SQLCommandRoot = "";

  public TableBuilderFrame(String tableName){
    setSize(600,400);
    setLocation(10,10);
    setClosable(true);
    setMaximizable(true);
    setIconifiable(true);
    setResizable(true);
    getContentPane().setLayout(new BorderLayout());
    this.tableName=tableName;
    SQLCommandRoot = "CREATE TABLE "+tableName;
    setTitle(SQLCommandRoot);
    init();
    setVisible(true);
  }

  // initialise the JInternalFrame
  private void init(){
    table = createTable(nRows);
    TableChangeListener modelListener = new TableChangeListener ();
    table.getModel().addTableModelListener(modelListener);
    JScrollPane sqlScroller = new JScrollPane(SQLPane);
    JScrollPane tableScroller = new JScrollPane(table);
    JSplitPane splitter = new
      JSplitPane(JSplitPane.VERTICAL_SPLIT,sqlScroller,tableScroller);
    splitter.setDividerLocation(100);
    getContentPane().add(splitter,BorderLayout.CENTER);
    getContentPane().add(createButton,BorderLayout.SOUTH);
    createButton.addActionListener(new ButtonListener());
  }
  private JTable createTable(int nRows){
    String[] dataTypes = {"","CHAR","VARCHAR","INT","FLOAT","DATE"};
    String[] defNull   = {"","NULL","NOT NULL"};
    String[] defUnique = {"","UNIQUE"};
    String[] defPriKey = {"","PRIMARY KEY"};
    String[] colNames  =
      {"Name","DataType","SIZE","NULL","UNIQUE","PRIMARY KEY"};
    String[][] rowData = new String[nRows][colNames.length];
    for(int i=0;i<nRows;i++){
      for(int j=0;j<colNames.length;j++)rowData[i][j]="";
    }
    JComboBox dTypes = new JComboBox(dataTypes);
    JComboBox nullDefs = new JComboBox(defNull);
    JComboBox uniqueDefs = new JComboBox(defUnique);
    JComboBox primaryKDefs = new JComboBox(defPriKey);
    JTable table = new JTable(rowData,colNames);
    table.getColumnModel().getColumn(1).
      setCellEditor(new DefaultCellEditor(dTypes));
    table.getColumnModel().getColumn(3).
      setCellEditor(new DefaultCellEditor(nullDefs));
    table.getColumnModel().getColumn(4).
      setCellEditor(new DefaultCellEditor(uniqueDefs));
    table.getColumnModel().getColumn(5).
      setCellEditor(new DefaultCellEditor(primaryKDefs));
    return table;
  }
  public String parseTable(){
    String tableValues = "";
    int rows = table.getRowCount();
    int cols = table.getColumnCount();

    if(rows>=0&&cols>=0){
      tableValues += "\n( ";
      for(int i=0;i<rows;i++){
        String rowData = "";
        for(int j=0;j<cols;j++){
          String field = (String)table.getValueAt(i,j);

          if(field!=null){
            if(field.length()==0)continue;
            if(j==2)rowData+="(";
            else if(i>0||j>0)rowData += "  ";
            rowData += field;
            if(j==2)rowData+=")";
          }
        }
        if(rowData.length()==0)break;
        tableValues += rowData+",\n";
      }
    }
    if(tableValues.endsWith(",\n")){
      int tvLen = tableValues.length()-2;
      if(tvLen>0)tableValues = tableValues.substring(0,tvLen);
    }
    tableValues += " );";
    return tableValues;
  }

  // CommandListener is set by the MVC Controller module as a call back to
  // return the SQL command
  public void setCommandListener(ActionListener commandListener){
    this.commandListener=commandListener;
  }
  // Listener for the CreateButton
  class ButtonListener implements ActionListener{
    public void actionPerformed(ActionEvent event){
      String action = event.getActionCommand();
      if(commandListener!=null){
        ActionEvent evt = new ActionEvent(this,0,SQLCommand);
        commandListener.actionPerformed(evt);
      }
    }
  }

  // Listener for Edit events on the JTable
  class TableChangeListener implements TableModelListener{
    public TableChangeListener (){
    }
    public void tableChanged(TableModelEvent event){
      SQLCommand = SQLCommandRoot+parseTable();
      SQLPane.setText(SQLCommand);
         }
     }
}