zauruseditor.java

hsqldb是100％java实现的数据库,是一个开放源代码的JAVA数据库 l 具有标准的SQL语法和JAVA接口 l HSQLDB可以自由使用和分发 l 非常简洁和快速的

     * structures for instance creating or dropping tables, or
     * altering tabel. The method will be called if one asks to
     * refresh the tree or if the connection to the database is
     * changed.
     *
     * @param c a <code>Connection</code> is the actual connection to
     * the database
     */
    public void refresh(Connection c) {

        cConn = c;

        if (vHoldForms == null) {
            this.initGUI();

            // System.out.println("initGUI <<<<<<<<<<<<<<<<<<<<<<");
        } else {
            this.resetTableForms();

            // System.out.println("reset >>>>>>>>>>>>>>>>>");
        }
    }

    private void initGUI() {

        // without connection there are no tables
        // vAllTables is a local variable with all table names in the database
        // vHoldTableNames holds the table names which have a ZaurusTableForm
        Vector vAllTables = getAllTables();

        if (vAllTables == null) {
            return;
        }

        // initialize a new list for the table names which have a form in pForm
        vHoldTableNames = new Vector(20);
        vHoldForms      = new Vector(20);

        // this holds the card panel pForm for the forms in the top
        // a card panel pButton below
        // the both card panels form a panel which is centered in this
        // and a status line in the south
        this.setLayout(new BorderLayout(3, 3));

        // >>> the top of this: the entry forms in pForm
        // pFormButs holds in the center the forms card panel pForm and
        // in the south the button card panel pButton
        Panel pFormButs = new Panel();

        pFormButs.setLayout(new BorderLayout(3, 3));

        pForm = new Panel();
        lForm = new CardLayout(2, 2);

        pForm.setLayout(lForm);

        // the search panel containing the list of all tables and
        // the entry fields for search words in the Center
        Panel pEntry = new Panel();

        pEntry.setLayout(new GridBagLayout());

        GridBagConstraints c = new GridBagConstraints();

        c.fill       = GridBagConstraints.HORIZONTAL;
        c.insets     = new Insets(3, 3, 3, 3);
        c.gridwidth  = 1;
        c.gridheight = 1;
        c.weightx    = c.weighty = 1;
        c.anchor     = GridBagConstraints.WEST;
        c.gridy      = 0;
        c.gridx      = 0;

        pEntry.add(new Label("Search table"), c);

        c.gridx = 1;

        // get all table names and show a drop down list of them in cTables
        cTables = new Choice();

        for (Enumeration e = vAllTables.elements(); e.hasMoreElements(); ) {
            cTables.addItem((String) e.nextElement());
        }

        c.gridwidth = 2;

        pEntry.add(cTables, c);

        c.gridy     = 1;
        c.gridx     = 0;
        c.gridwidth = 1;

        pEntry.add(new Label("Search words"), c);

        c.gridx      = 1;
        c.gridwidth  = 2;
        fSearchWords = new TextField(8);

        pEntry.add(fSearchWords, c);

        // use search words
        c.gridwidth = 1;
        c.gridy     = 2;
        c.gridx     = 0;

        pEntry.add(new Label("Use search words"), c);

        gAllWords = new CheckboxGroup();

        Checkbox[] checkboxes = new Checkbox[2];

        checkboxes[0] = new Checkbox("all", gAllWords, true);
        c.gridx       = 1;

        pEntry.add(checkboxes[0], c);

        checkboxes[1] = new Checkbox("any ", gAllWords, false);
        c.gridx       = 2;

        pEntry.add(checkboxes[1], c);

        // ignore case
        c.gridy = 3;
        c.gridx = 0;

        pEntry.add(new Label("Ignore case"), c);

        gIgnoreCase = new CheckboxGroup();

        Checkbox[] checkboxes1 = new Checkbox[2];

        checkboxes1[0] = new Checkbox("yes", gIgnoreCase, true);
        c.gridx        = 1;

        pEntry.add(checkboxes1[0], c);

        checkboxes1[1] = new Checkbox("no", gIgnoreCase, false);
        c.gridx        = 2;

        pEntry.add(checkboxes1[1], c);

        // Match column exactly
        c.gridy = 4;
        c.gridx = 0;

        pEntry.add(new Label("Match whole col"), c);

        gNoMatchWhole = new CheckboxGroup();

        Checkbox[] checkboxes2 = new Checkbox[2];

        checkboxes2[0] = new Checkbox("no", gNoMatchWhole, true);
        c.gridx        = 1;

        pEntry.add(checkboxes2[0], c);

        checkboxes2[1] = new Checkbox("yes ", gNoMatchWhole, false);
        c.gridx        = 2;

        pEntry.add(checkboxes2[1], c);
        pForm.add("search", pEntry);
        pFormButs.add("Center", pForm);

        // the buttons
        this.initButtons();

        pButton = new Panel();
        lButton = new CardLayout(2, 2);

        pButton.setLayout(lButton);
        pButton.add("search", pSearchButs);
        pButton.add("edit", pEditButs);
        pButton.add("insert", pInsertButs);
        pFormButs.add("South", pButton);
        this.add("Center", pFormButs);

        // >>> the South: status line at the bottom
        Font fFont = new Font("Dialog", Font.PLAIN, 10);

        ZaurusEditor.tStatus = new TextField("");

        ZaurusEditor.tStatus.setEditable(false);
        this.add("South", ZaurusEditor.tStatus);
    }

    // process the buttons events
    // *******************************************************
    // private methods
    // *******************************************************
    // read all table names over the current database connection
    // exclude tables without primary key
    private Vector getAllTables() {

        Vector result = new Vector(20);

        try {
            if (cConn == null) {
                return null;
            }

            dbmeta = cConn.getMetaData();

            String[] tableTypes = { "TABLE" };
            ResultSet allTables = dbmeta.getTables(null, null, null,
                                                   tableTypes);

            while (allTables.next()) {
                String aktTable = allTables.getString("TABLE_NAME");
                ResultSet primKeys = dbmeta.getPrimaryKeys(null, null,
                    aktTable);

                // take only table with a primary key
                if (primKeys.next()) {
                    result.addElement(aktTable);
                }

                primKeys.close();
            }

            allTables.close();
        } catch (SQLException e) {

            // System.out.println("SQL Exception: " + e.getMessage());
        }

        return result;
    }

    // determine the index of the choosen table in Vector vHoldTableNames
    // if the table name is not in vHoldTableNames, create a ZaurusTableForm for it
    private int getChoosenTableIndex() {

        String tableName = cTables.getSelectedItem();

        // System.out.println("in getChoosenTableIndex, selected Item is "+tableName);
        int index = getTableIndex(tableName);

        if (index >= 0) {

            // System.out.println("table found, index: " + index);
            return index;
        }    // end of if (index >= 0)

        ZaurusTableForm tableForm = new ZaurusTableForm(tableName, cConn);

        pForm.add(tableName, tableForm);
        vHoldTableNames.addElement(tableName);
        vHoldForms.addElement(tableForm);

        // System.out.println("new tableform for table "+tableName+", index: " + index);
        return vHoldTableNames.size() - 1;
    }

    // determine the index of the given tableName in Vector vHoldTableNames
    // if the name is not in vHoldTableNames, answer -1
    private int getTableIndex(String tableName) {

        int index;

        // System.out.println("begin searching for "+tableName);
        for (index = 0; index < vHoldTableNames.size(); index++) {

            // System.out.println("in getTableIndex searching for "+tableName+", index: "+index);
            if (tableName.equals((String) vHoldTableNames.elementAt(index))) {
                return index;
            }    // end of if (tableName.equals(vHoldTableNames.elementAt(index)))
        }        // end of for (index = 0; index < vHoldTableNames.size(); index ++)

        return -1;
    }

    // convert the search words in the textfield to an array of words
    private String[] getWords() {

        StringTokenizer tokenizer =
            new StringTokenizer(fSearchWords.getText());
        String[] result = new String[tokenizer.countTokens()];
        int      i      = 0;

        while (tokenizer.hasMoreTokens()) {
            result[i++] = tokenizer.nextToken();
        }    // end of while ((tokenizer.hasMoreTokens()))

        return result;
    }

    // init the three boxes for buttons
    private void initButtons() {

        // the buttons for the search form
        bSearchRow = new Button("Search Rows");
        bNewRow    = new Button("Insert New Row");

        bSearchRow.addActionListener(this);
        bNewRow.addActionListener(this);

        pSearchButs = new Panel();

        pSearchButs.setLayout(new GridLayout(1, 0, 4, 4));
        pSearchButs.add(bSearchRow);
        pSearchButs.add(bNewRow);

        // the buttons for editing a row
        bCancel1         = new Button("Cancel");
        bPrev            = new Button("Prev");
        bNext            = new Button("Next");
        bDelete          = new Button("Delete");
        lastButtonDelete = false;
        bNewSearch       = new Button("Search");

        bCancel1.addActionListener(this);
        bPrev.addActionListener(this);
        bNext.addActionListener(this);
        bDelete.addActionListener(this);
        bNewSearch.addActionListener(this);

        pEditButs = new Panel();

        pEditButs.setLayout(new GridLayout(1, 0, 4, 4));
        pEditButs.add(bCancel1);
        pEditButs.add(bPrev);
        pEditButs.add(bNext);
        pEditButs.add(bDelete);
        pEditButs.add(bNewSearch);

        // the buttons for inserting a new row
        pInsertButs = new Panel();

        pInsertButs.setLayout(new GridLayout(1, 0, 4, 4));

        bCancel2    = new Button("Cancel Insert");
        bNewInsert  = new Button("New Insert");
        bNewSearch1 = new Button("Search");

        bCancel2.addActionListener(this);
        bNewInsert.addActionListener(this);
        bNewSearch1.addActionListener(this);
        pInsertButs.add(bCancel2);
        pInsertButs.add(bNewInsert);
        pInsertButs.add(bNewSearch1);
    }

    // check whether the last button pressed was delete
    // if so, clear status line and reset the flag
    private void resetLastButtonDelete() {

        if (lastButtonDelete) {
            ZaurusEditor.printStatus("");

            lastButtonDelete = false;
        }    // end of if (lastButtonDelete)
    }

    // reset  everything after changes in the database
    private void resetTableForms() {

        lForm.show(pForm, "search");
        lButton.show(pButton, "search");

        Vector vAllTables = getAllTables();

        // fill the drop down list again
        // get all table names and show a drop down list of them in cTables
        cTables.removeAll();

        for (Enumeration e = vAllTables.elements(); e.hasMoreElements(); ) {
            cTables.addItem((String) e.nextElement());
        }

        // remove all form panels from pForm
        for (Enumeration e = vHoldForms.elements(); e.hasMoreElements(); ) {
            pForm.remove((ZaurusTableForm) e.nextElement());
        }    // end of while (Enumeration e = vHoldForms.elements(); e.hasMoreElements();)

        // initialize a new list for the table names which have a form in pForm
        vHoldTableNames = new Vector(20);
        vHoldForms      = new Vector(20);
    }
}