source: josm/src/org/openstreetmap/josm/actions/UploadAction.java@ 52

package org.openstreetmap.josm.actions;

import java.awt.GridBagLayout;
import java.awt.event.ActionEvent;
import java.awt.event.InputEvent;
import java.awt.event.KeyEvent;
import java.util.Collection;
import java.util.LinkedList;

import javax.swing.JLabel;
import javax.swing.JList;
import javax.swing.JOptionPane;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.KeyStroke;

import org.jdom.JDOMException;
import org.openstreetmap.josm.Main;
import org.openstreetmap.josm.data.osm.OsmPrimitive;
import org.openstreetmap.josm.data.osm.Track;
import org.openstreetmap.josm.gui.GBC;
import org.openstreetmap.josm.gui.OsmPrimitivRenderer;
import org.openstreetmap.josm.io.OsmServerWriter;

/**
 * Action that opens a connection to the osm server and upload all changes.
 * 
 * An dialog is displayed asking the user to specify a rectangle to grab.
 * The url and account settings from the preferences are used.
 *  
 * @author imi
 */
public class UploadAction extends JosmAction {

        public UploadAction() {
                super("Upload to OSM", "upload", "Upload all changes to the OSM server.", KeyEvent.VK_U, 
                                KeyStroke.getAWTKeyStroke(KeyEvent.VK_U, InputEvent.CTRL_DOWN_MASK | InputEvent.SHIFT_DOWN_MASK));
        }

        public void actionPerformed(ActionEvent e) {
                final Collection<OsmPrimitive> add = new LinkedList<OsmPrimitive>();
                final Collection<OsmPrimitive> update = new LinkedList<OsmPrimitive>();
                final Collection<OsmPrimitive> delete = new LinkedList<OsmPrimitive>();
                boolean acceptedTracks = false;
                for (OsmPrimitive osm : Main.main.ds.allPrimitives()) {
                        boolean doSomething = true;
                        if (osm.id == 0 && !osm.isDeleted())
                                add.add(osm);
                        else if ((osm.modified || osm.modifiedProperties) && !osm.isDeleted())
                                update.add(osm);
                        else if (osm.isDeleted() && osm.id != 0)
                                delete.add(osm);
                        else
                                doSomething = false;

                        if (osm instanceof Track && doSomething && !acceptedTracks) {
                                int answer = JOptionPane.showConfirmDialog(Main.main, 
                                                "The server currently does not understand the concept of Tracks.\n" +
                                                "All tracks will be ignored on upload. Continue anyway?",
                                                "No Track support", JOptionPane.YES_NO_OPTION);
                                if (answer != JOptionPane.YES_OPTION)
                                        return;
                                acceptedTracks = true;
                        }
                }

                if (!displayUploadScreen(add, update, delete))
                        return;

                final OsmServerWriter server = new OsmServerWriter();
                final Collection<OsmPrimitive> all = new LinkedList<OsmPrimitive>();
                all.addAll(add);
                all.addAll(update);
                all.addAll(delete);
                
                new Thread(new PleaseWaitRunnable("Uploading data"){
                        @Override
                        public void realRun() {
                                try {
                                        server.uploadOsm(all);
                                } catch (JDOMException x) {
                                        closeDialog();
                                        x.printStackTrace();
                                        JOptionPane.showMessageDialog(Main.main, x.getMessage());
                                }
                                Main.main.getMapFrame().mapView.editLayer().cleanData(server.processed, !add.isEmpty());
                        }
                }).start();
        }
        
        /**
         * Displays a screen where the actions that would be taken are displayed and
         * give the user the possibility to cancel the upload.
         * @return <code>true</code>, if the upload should continue. <code>false</code>
         *                      if the user requested cancel.
         */
        private boolean displayUploadScreen(Collection<OsmPrimitive> add, Collection<OsmPrimitive> update, Collection<OsmPrimitive> delete) {
                if (add.isEmpty() && update.isEmpty() && delete.isEmpty()) {
                        JOptionPane.showMessageDialog(Main.main, "No changes to upload.");
                        return false;
                }

                JPanel p = new JPanel(new GridBagLayout());

                OsmPrimitivRenderer renderer = new OsmPrimitivRenderer();

                if (!add.isEmpty()) {
                        p.add(new JLabel("Objects to add:"), GBC.eol());
                        JList l = new JList(add.toArray());
                        l.setCellRenderer(renderer);
                        l.setVisibleRowCount(l.getModel().getSize() < 6 ? l.getModel().getSize() : 10);
                        p.add(new JScrollPane(l), GBC.eol().fill());
                }

                if (!update.isEmpty()) {
                        p.add(new JLabel("Objects to modify:"), GBC.eol());
                        JList l = new JList(update.toArray());
                        l.setCellRenderer(renderer);
                        l.setVisibleRowCount(l.getModel().getSize() < 6 ? l.getModel().getSize() : 10);
                        p.add(new JScrollPane(l), GBC.eol().fill());
                }

                if (!delete.isEmpty()) {
                        p.add(new JLabel("Objects to delete:"), GBC.eol());
                        JList l = new JList(delete.toArray());
                        l.setCellRenderer(renderer);
                        l.setVisibleRowCount(l.getModel().getSize() < 6 ? l.getModel().getSize() : 10);
                        p.add(new JScrollPane(l), GBC.eol().fill());
                }

                return JOptionPane.showConfirmDialog(Main.main, p, "Upload this changes?", 
                                JOptionPane.YES_NO_OPTION) == JOptionPane.YES_OPTION;
        }
}