Java tutorial
/* From http://java.sun.com/docs/books/tutorial/index.html */ /* * Copyright (c) 2006 Sun Microsystems, Inc. All Rights Reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions are met: * * -Redistribution of source code must retain the above copyright notice, this * list of conditions and the following disclaimer. * * -Redistribution in binary form must reproduce the above copyright notice, * this list of conditions and the following disclaimer in the documentation * and/or other materials provided with the distribution. * * Neither the name of Sun Microsystems, Inc. or the names of contributors may * be used to endorse or promote products derived from this software without * specific prior written permission. * * This software is provided "AS IS," without a warranty of any kind. ALL * EXPRESS OR IMPLIED CONDITIONS, REPRESENTATIONS AND WARRANTIES, INCLUDING * ANY IMPLIED WARRANTY OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE * OR NON-INFRINGEMENT, ARE HEREBY EXCLUDED. SUN MIDROSYSTEMS, INC. ("SUN") * AND ITS LICENSORS SHALL NOT BE LIABLE FOR ANY DAMAGES SUFFERED BY LICENSEE * AS A RESULT OF USING, MODIFYING OR DISTRIBUTING THIS SOFTWARE OR ITS * DERIVATIVES. IN NO EVENT WILL SUN OR ITS LICENSORS BE LIABLE FOR ANY LOST * REVENUE, PROFIT OR DATA, OR FOR DIRECT, INDIRECT, SPECIAL, CONSEQUENTIAL, * INCIDENTAL OR PUNITIVE DAMAGES, HOWEVER CAUSED AND REGARDLESS OF THE THEORY * OF LIABILITY, ARISING OUT OF THE USE OF OR INABILITY TO USE THIS SOFTWARE, * EVEN IF SUN HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES. * * You acknowledge that this software is not designed, licensed or intended * for use in the design, construction, operation or maintenance of any * nuclear facility. */ /* * ExtendedDnDDemo.java is a 1.4 example that requires the following files: * StringTransferHandler.java ListTransferHandler.java TableTransferHandler.java */ import java.awt.BorderLayout; import java.awt.Dimension; import java.awt.GridLayout; import java.awt.datatransfer.DataFlavor; import java.awt.datatransfer.StringSelection; import java.awt.datatransfer.Transferable; import java.awt.datatransfer.UnsupportedFlavorException; import java.io.IOException; import javax.swing.BorderFactory; import javax.swing.DefaultListModel; import javax.swing.JComponent; import javax.swing.JFrame; import javax.swing.JList; import javax.swing.JPanel; import javax.swing.JScrollPane; import javax.swing.JTable; import javax.swing.JTextArea; import javax.swing.ListSelectionModel; import javax.swing.TransferHandler; import javax.swing.table.DefaultTableModel; public class ExtendedDnDDemo extends JPanel { public ExtendedDnDDemo() { super(new GridLayout(3, 1)); add(createArea()); add(createList()); add(createTable()); } private JPanel createList() { DefaultListModel listModel = new DefaultListModel(); listModel.addElement("List 0"); listModel.addElement("List 1"); listModel.addElement("List 2"); listModel.addElement("List 3"); listModel.addElement("List 4"); listModel.addElement("List 5"); listModel.addElement("List 6"); listModel.addElement("List 7"); listModel.addElement("List 8"); JList list = new JList(listModel); list.setSelectionMode(ListSelectionModel.SINGLE_INTERVAL_SELECTION); JScrollPane scrollPane = new JScrollPane(list); scrollPane.setPreferredSize(new Dimension(400, 100)); list.setDragEnabled(true); list.setTransferHandler(new ListTransferHandler()); JPanel panel = new JPanel(new BorderLayout()); panel.add(scrollPane, BorderLayout.CENTER); panel.setBorder(BorderFactory.createTitledBorder("List")); return panel; } private JPanel createArea() { String text = "This is the text that I want to show."; JTextArea area = new JTextArea(); area.setText(text); area.setDragEnabled(true); JScrollPane scrollPane = new JScrollPane(area); scrollPane.setPreferredSize(new Dimension(400, 100)); JPanel panel = new JPanel(new BorderLayout()); panel.add(scrollPane, BorderLayout.CENTER); panel.setBorder(BorderFactory.createTitledBorder("Text Area")); return panel; } private JPanel createTable() { DefaultTableModel model = new DefaultTableModel(); model.addColumn("Column 0"); model.addColumn("Column 1"); model.addColumn("Column 2"); model.addColumn("Column 3"); model.addRow(new String[] { "Table 00", "Table 01", "Table 02", "Table 03" }); model.addRow(new String[] { "Table 10", "Table 11", "Table 12", "Table 13" }); model.addRow(new String[] { "Table 20", "Table 21", "Table 22", "Table 23" }); model.addRow(new String[] { "Table 30", "Table 31", "Table 32", "Table 33" }); JTable table = new JTable(model); table.getTableHeader().setReorderingAllowed(false); table.setSelectionMode(ListSelectionModel.SINGLE_INTERVAL_SELECTION); JScrollPane scrollPane = new JScrollPane(table); scrollPane.setPreferredSize(new Dimension(400, 100)); table.setDragEnabled(true); table.setTransferHandler(new TableTransferHandler()); JPanel panel = new JPanel(new BorderLayout()); panel.add(scrollPane, BorderLayout.CENTER); panel.setBorder(BorderFactory.createTitledBorder("Table")); return panel; } /** * Create the GUI and show it. For thread safety, this method should be * invoked from the event-dispatching thread. */ private static void createAndShowGUI() { //Make sure we have nice window decorations. JFrame.setDefaultLookAndFeelDecorated(true); //Create and set up the window. JFrame frame = new JFrame("ExtendedDnDDemo"); frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); //Create and set up the content pane. JComponent newContentPane = new ExtendedDnDDemo(); newContentPane.setOpaque(true); //content panes must be opaque frame.setContentPane(newContentPane); //Display the window. frame.pack(); frame.setVisible(true); } public static void main(String[] args) { //Schedule a job for the event-dispatching thread: //creating and showing this application's GUI. javax.swing.SwingUtilities.invokeLater(new Runnable() { public void run() { createAndShowGUI(); } }); } } /* * ListTransferHandler.java is used by the 1.4 ExtendedDnDDemo.java example. */ class ListTransferHandler extends StringTransferHandler { private int[] indices = null; private int addIndex = -1; //Location where items were added private int addCount = 0; //Number of items added. //Bundle up the selected items in the list //as a single string, for export. protected String exportString(JComponent c) { JList list = (JList) c; indices = list.getSelectedIndices(); Object[] values = list.getSelectedValues(); StringBuffer buff = new StringBuffer(); for (int i = 0; i < values.length; i++) { Object val = values[i]; buff.append(val == null ? "" : val.toString()); if (i != values.length - 1) { buff.append("\n"); } } return buff.toString(); } //Take the incoming string and wherever there is a //newline, break it into a separate item in the list. protected void importString(JComponent c, String str) { JList target = (JList) c; DefaultListModel listModel = (DefaultListModel) target.getModel(); int index = target.getSelectedIndex(); //Prevent the user from dropping data back on itself. //For example, if the user is moving items #4,#5,#6 and #7 and //attempts to insert the items after item #5, this would //be problematic when removing the original items. //So this is not allowed. if (indices != null && index >= indices[0] - 1 && index <= indices[indices.length - 1]) { indices = null; return; } int max = listModel.getSize(); if (index < 0) { index = max; } else { index++; if (index > max) { index = max; } } addIndex = index; String[] values = str.split("\n"); addCount = values.length; for (int i = 0; i < values.length; i++) { listModel.add(index++, values[i]); } } //If the remove argument is true, the drop has been //successful and it's time to remove the selected items //from the list. If the remove argument is false, it //was a Copy operation and the original list is left //intact. protected void cleanup(JComponent c, boolean remove) { if (remove && indices != null) { JList source = (JList) c; DefaultListModel model = (DefaultListModel) source.getModel(); //If we are moving items around in the same list, we //need to adjust the indices accordingly, since those //after the insertion point have moved. if (addCount > 0) { for (int i = 0; i < indices.length; i++) { if (indices[i] > addIndex) { indices[i] += addCount; } } } for (int i = indices.length - 1; i >= 0; i--) { model.remove(indices[i]); } } indices = null; addCount = 0; addIndex = -1; } } /* * StringTransferHandler.java is used by the 1.4 ExtendedDnDDemo.java example. */ abstract class StringTransferHandler extends TransferHandler { protected abstract String exportString(JComponent c); protected abstract void importString(JComponent c, String str); protected abstract void cleanup(JComponent c, boolean remove); protected Transferable createTransferable(JComponent c) { return new StringSelection(exportString(c)); } public int getSourceActions(JComponent c) { return COPY_OR_MOVE; } public boolean importData(JComponent c, Transferable t) { if (canImport(c, t.getTransferDataFlavors())) { try { String str = (String) t.getTransferData(DataFlavor.stringFlavor); importString(c, str); return true; } catch (UnsupportedFlavorException ufe) { } catch (IOException ioe) { } } return false; } protected void exportDone(JComponent c, Transferable data, int action) { cleanup(c, action == MOVE); } public boolean canImport(JComponent c, DataFlavor[] flavors) { for (int i = 0; i < flavors.length; i++) { if (DataFlavor.stringFlavor.equals(flavors[i])) { return true; } } return false; } } /* * TableTransferHandler.java is used by the 1.4 ExtendedDnDDemo.java example. */ class TableTransferHandler extends StringTransferHandler { private int[] rows = null; private int addIndex = -1; //Location where items were added private int addCount = 0; //Number of items added. protected String exportString(JComponent c) { JTable table = (JTable) c; rows = table.getSelectedRows(); int colCount = table.getColumnCount(); StringBuffer buff = new StringBuffer(); for (int i = 0; i < rows.length; i++) { for (int j = 0; j < colCount; j++) { Object val = table.getValueAt(rows[i], j); buff.append(val == null ? "" : val.toString()); if (j != colCount - 1) { buff.append(","); } } if (i != rows.length - 1) { buff.append("\n"); } } return buff.toString(); } protected void importString(JComponent c, String str) { JTable target = (JTable) c; DefaultTableModel model = (DefaultTableModel) target.getModel(); int index = target.getSelectedRow(); //Prevent the user from dropping data back on itself. //For example, if the user is moving rows #4,#5,#6 and #7 and //attempts to insert the rows after row #5, this would //be problematic when removing the original rows. //So this is not allowed. if (rows != null && index >= rows[0] - 1 && index <= rows[rows.length - 1]) { rows = null; return; } int max = model.getRowCount(); if (index < 0) { index = max; } else { index++; if (index > max) { index = max; } } addIndex = index; String[] values = str.split("\n"); addCount = values.length; int colCount = target.getColumnCount(); for (int i = 0; i < values.length && i < colCount; i++) { model.insertRow(index++, values[i].split(",")); } } protected void cleanup(JComponent c, boolean remove) { JTable source = (JTable) c; if (remove && rows != null) { DefaultTableModel model = (DefaultTableModel) source.getModel(); //If we are moving items around in the same table, we //need to adjust the rows accordingly, since those //after the insertion point have moved. if (addCount > 0) { for (int i = 0; i < rows.length; i++) { if (rows[i] > addIndex) { rows[i] += addCount; } } } for (int i = rows.length - 1; i >= 0; i--) { model.removeRow(rows[i]); } } rows = null; addCount = 0; addIndex = -1; } }