001    // License: GPL. For details, see LICENSE file.
002    package org.openstreetmap.josm.gui.dialogs.relation;
003    
004    import static org.openstreetmap.josm.tools.I18n.tr;
005    
006    import java.awt.Component;
007    import java.awt.Dialog;
008    import java.io.IOException;
009    
010    import javax.swing.JTree;
011    import javax.swing.SwingUtilities;
012    import javax.swing.event.TreeExpansionEvent;
013    import javax.swing.event.TreeWillExpandListener;
014    import javax.swing.tree.ExpandVetoException;
015    import javax.swing.tree.TreePath;
016    
017    import org.openstreetmap.josm.Main;
018    import org.openstreetmap.josm.data.osm.DataSet;
019    import org.openstreetmap.josm.data.osm.DataSetMerger;
020    import org.openstreetmap.josm.data.osm.OsmPrimitiveType;
021    import org.openstreetmap.josm.data.osm.Relation;
022    import org.openstreetmap.josm.gui.PleaseWaitRunnable;
023    import org.openstreetmap.josm.gui.progress.PleaseWaitProgressMonitor;
024    import org.openstreetmap.josm.gui.progress.ProgressMonitor;
025    import org.openstreetmap.josm.io.OsmApi;
026    import org.openstreetmap.josm.io.OsmServerObjectReader;
027    import org.openstreetmap.josm.io.OsmTransferException;
028    import org.xml.sax.SAXException;
029    
030    /**
031     * This is a {@link JTree} rendering the hierarchical structure of {@link Relation}s.
032     *
033     * @see RelationTreeModel
034     */
035    public class RelationTree extends JTree {
036        /**
037         * builds the UI
038         */
039        protected void build() {
040            setRootVisible(false);
041            setCellRenderer(new RelationTreeCellRenderer());
042            addTreeWillExpandListener(new LazyRelationLoader());
043        }
044    
045        /**
046         * constructor
047         */
048        public RelationTree(){
049            super();
050            build();
051        }
052    
053        /**
054         * constructor
055         * @param model the tree model
056         */
057        public RelationTree(RelationTreeModel model) {
058            super(model);
059            build();
060        }
061    
062        /**
063         * replies the parent dialog this tree is embedded in.
064         *
065         * @return the parent dialog; null, if there is no parent dialog
066         */
067        protected Dialog getParentDialog() {
068            Component c = RelationTree.this;
069            while(c != null && ! (c instanceof Dialog)) {
070                c = c.getParent();
071            }
072            return (Dialog)c;
073        }
074    
075        /**
076         * An adapter for TreeWillExpand-events. If a node is to be expanded which is
077         * not loaded yet this will trigger asynchronous loading of the respective
078         * relation.
079         *
080         */
081        class LazyRelationLoader implements TreeWillExpandListener {
082    
083            public void treeWillCollapse(TreeExpansionEvent event) throws ExpandVetoException {
084                // do nothing
085            }
086    
087            public void treeWillExpand(TreeExpansionEvent event) throws ExpandVetoException {
088                TreePath path  = event.getPath();
089                Relation parent = (Relation)event.getPath().getLastPathComponent();
090                if (! parent.isIncomplete() || parent.isNew())
091                    // we don't load complete  or new relations
092                    return;
093                // launch the download task
094                //
095                Main.worker.submit(new RelationLoader(getParentDialog(),parent, path));
096            }
097        }
098    
099        /**
100         * Asynchronous download task for a specific relation
101         *
102         */
103        class RelationLoader extends PleaseWaitRunnable {
104            private boolean canceled;
105            private Exception lastException;
106            private Relation relation;
107            private DataSet ds;
108            private TreePath path;
109    
110            public RelationLoader(Dialog dialog, Relation relation, TreePath path) {
111                super(
112                        tr("Load relation"),
113                        new PleaseWaitProgressMonitor(
114                                dialog
115                        ),
116                        false /* don't ignore exceptions */
117                );
118                this.relation = relation;
119                this.path = path;
120            }
121            @Override
122            protected void cancel() {
123                OsmApi.getOsmApi().cancel();
124                this.canceled = true;
125            }
126    
127            @Override
128            protected void finish() {
129                if (canceled)
130                    return;
131                if (lastException != null) {
132                    lastException.printStackTrace();
133                    return;
134                }
135                DataSetMerger visitor = new DataSetMerger(Main.main.getEditLayer().data, ds);
136                visitor.merge();
137                if (! visitor.getConflicts().isEmpty()) {
138                    Main.main.getEditLayer().getConflicts().add(visitor.getConflicts());
139                }
140                final RelationTreeModel model = (RelationTreeModel)getModel();
141                SwingUtilities.invokeLater(
142                        new Runnable() {
143                            public void run() {
144                                model.refreshNode(path);
145                            }
146                        }
147                );
148            }
149    
150            @Override
151            protected void realRun() throws SAXException, IOException, OsmTransferException {
152                try {
153                    OsmServerObjectReader reader = new OsmServerObjectReader(relation.getId(), OsmPrimitiveType.from(relation), true /* full load */);
154                    ds = reader.parseOsm(progressMonitor
155                            .createSubTaskMonitor(ProgressMonitor.ALL_TICKS, false));
156                } catch(Exception e) {
157                    if (canceled) {
158                        System.out.println(tr("Warning: Ignoring exception because task was canceled. Exception: {0}", e.toString()));
159                        return;
160                    }
161                    this.lastException = e;
162                }
163            }
164        }
165    }