bundles/org.simantics.diagram/src/org/simantics/diagram/participant/ConnectTool2.java

   1 /*******************************************************************************
   2  * Copyright (c) 2007, 2010 Association for Decentralized Information Management
   3  * in Industry THTH ry.
   4  * All rights reserved. This program and the accompanying materials
   5  * are made available under the terms of the Eclipse Public License v1.0
   6  * which accompanies this distribution, and is available at
   7  * http://www.eclipse.org/legal/epl-v10.html
   8  *
   9  * Contributors:
  10  *     VTT Technical Research Centre of Finland - initial API and implementation
  11  *******************************************************************************/
  12 package org.simantics.diagram.participant;
  13
  14 import java.awt.AlphaComposite;
  15 import java.awt.BasicStroke;
  16 import java.awt.Color;
  17 import java.awt.Composite;
  18 import java.awt.geom.AffineTransform;
  19 import java.awt.geom.Path2D;
  20 import java.awt.geom.Point2D;
  21 import java.awt.geom.Rectangle2D;
  22 import java.util.ArrayDeque;
  23 import java.util.ArrayList;
  24 import java.util.Arrays;
  25 import java.util.Collection;
  26 import java.util.Collections;
  27 import java.util.Deque;
  28 import java.util.Iterator;
  29 import java.util.List;
  30
  31 import org.simantics.Simantics;
  32 import org.simantics.db.ReadGraph;
  33 import org.simantics.db.Resource;
  34 import org.simantics.db.WriteGraph;
  35 import org.simantics.db.common.request.UniqueRead;
  36 import org.simantics.db.common.request.WriteRequest;
  37 import org.simantics.db.common.utils.NameUtils;
  38 import org.simantics.db.exception.DatabaseException;
  39 import org.simantics.diagram.connection.RouteGraph;
  40 import org.simantics.diagram.connection.RouteGraphConnectionClass;
  41 import org.simantics.diagram.connection.RouteLine;
  42 import org.simantics.diagram.connection.RouteTerminal;
  43 import org.simantics.diagram.connection.delta.RouteGraphDelta;
  44 import org.simantics.diagram.connection.rendering.arrows.PlainLineEndStyle;
  45 import org.simantics.diagram.content.ResourceTerminal;
  46 import org.simantics.diagram.stubs.DiagramResource;
  47 import org.simantics.diagram.synchronization.ISynchronizationContext;
  48 import org.simantics.diagram.synchronization.SynchronizationHints;
  49 import org.simantics.diagram.synchronization.graph.RouteGraphConnection;
  50 import org.simantics.g2d.canvas.ICanvasContext;
  51 import org.simantics.g2d.canvas.impl.DependencyReflection.Dependency;
  52 import org.simantics.g2d.canvas.impl.DependencyReflection.Reference;
  53 import org.simantics.g2d.canvas.impl.SGNodeReflection.SGCleanup;
  54 import org.simantics.g2d.canvas.impl.SGNodeReflection.SGInit;
  55 import org.simantics.g2d.connection.IConnectionAdvisor;
  56 import org.simantics.g2d.diagram.DiagramHints;
  57 import org.simantics.g2d.diagram.DiagramUtils;
  58 import org.simantics.g2d.diagram.IDiagram;
  59 import org.simantics.g2d.diagram.handler.PickContext;
  60 import org.simantics.g2d.diagram.handler.Topology.Terminal;
  61 import org.simantics.g2d.diagram.participant.ElementPainter;
  62 import org.simantics.g2d.diagram.participant.TerminalPainter;
  63 import org.simantics.g2d.diagram.participant.TerminalPainter.TerminalHoverStrategy;
  64 import org.simantics.g2d.diagram.participant.pointertool.AbstractMode;
  65 import org.simantics.g2d.diagram.participant.pointertool.PointerInteractor;
  66 import org.simantics.g2d.diagram.participant.pointertool.TerminalUtil;
  67 import org.simantics.g2d.diagram.participant.pointertool.TerminalUtil.TerminalInfo;
  68 import org.simantics.g2d.element.ElementClass;
  69 import org.simantics.g2d.element.ElementClasses;
  70 import org.simantics.g2d.element.ElementUtils;
  71 import org.simantics.g2d.element.IElement;
  72 import org.simantics.g2d.element.IElementClassProvider;
  73 import org.simantics.g2d.element.handler.EdgeVisuals.EdgeEnd;
  74 import org.simantics.g2d.element.handler.SceneGraph;
  75 import org.simantics.g2d.element.handler.TerminalTopology;
  76 import org.simantics.g2d.element.handler.impl.BranchPointTerminal;
  77 import org.simantics.g2d.element.impl.Element;
  78 import org.simantics.g2d.elementclass.BranchPoint;
  79 import org.simantics.g2d.elementclass.BranchPoint.Direction;
  80 import org.simantics.g2d.elementclass.FlagClass;
  81 import org.simantics.g2d.elementclass.FlagHandler;
  82 import org.simantics.g2d.participant.RenderingQualityInteractor;
  83 import org.simantics.g2d.participant.TransformUtil;
  84 import org.simantics.g2d.utils.geom.DirectionSet;
  85 import org.simantics.modeling.ModelingResources;
  86 import org.simantics.scenegraph.g2d.G2DParentNode;
  87 import org.simantics.scenegraph.g2d.events.EventHandlerReflection.EventHandler;
  88 import org.simantics.scenegraph.g2d.events.KeyEvent;
  89 import org.simantics.scenegraph.g2d.events.KeyEvent.KeyPressedEvent;
  90 import org.simantics.scenegraph.g2d.events.MouseEvent;
  91 import org.simantics.scenegraph.g2d.events.MouseEvent.MouseButtonEvent;
  92 import org.simantics.scenegraph.g2d.events.MouseEvent.MouseButtonPressedEvent;
  93 import org.simantics.scenegraph.g2d.events.MouseEvent.MouseButtonReleasedEvent;
  94 import org.simantics.scenegraph.g2d.events.MouseEvent.MouseMovedEvent;
  95 import org.simantics.scenegraph.g2d.events.command.CommandEvent;
  96 import org.simantics.scenegraph.g2d.events.command.Commands;
  97 import org.simantics.scenegraph.g2d.nodes.BranchPointNode;
  98 import org.simantics.scenegraph.g2d.nodes.ShapeNode;
  99 import org.simantics.scenegraph.g2d.snap.ISnapAdvisor;
 100 import org.simantics.scenegraph.utils.GeometryUtils;
 101 import org.simantics.scenegraph.utils.Quality;
 102 import org.simantics.structural2.modelingRules.ConnectionJudgement;
 103 import org.simantics.utils.datastructures.Pair;
 104 import org.simantics.utils.logging.TimeLogger;
 105 import org.simantics.utils.ui.ErrorLogger;
 106 import org.simantics.utils.ui.ExceptionUtils;
 107
 108 import gnu.trove.map.hash.THashMap;
 109
 110 /**
 111  * A basic tool for making connection on diagrams.
 112  *
 113  * This version defines the starting, ending and route points of a connection.
 114  * The routing itself is left up to the diagram router employed by
 115  * {@link DiagramUtils#validateAndFix(IDiagram, ICanvasContext)}.
 116  *
 117  * Manual:
 118  *
 119  * This tool is added to the diagram when a connection sequence is initiated by
 120  * another participant. PointerInteractor is one such participant which adds the
 121  * tool when a terminal or non-terminal-occupied canvas space is ALT+clicked
 122  * (see {@link PointerInteractor#checkInitiateConnectTool(MouseEvent, Point2D)}
 123  * ). The connection will be finished when another allowed terminal is clicked
 124  * upon or empty canvas space is ALT+clicked. Route points for the connection
 125  * can be created by clicking around on non-terminal-occupied canvas space while
 126  * connecting.
 127  *
 128  * <p>
 129  * Connections can be started from and ended in flags by pressing ALT while
 130  * left-clicking.
 131  *
 132  * @author Tuukka Lehtonen
 133  */
 134 public class ConnectTool2 extends AbstractMode {
 135
 136     public static final int          PAINT_PRIORITY        = ElementPainter.ELEMENT_PAINT_PRIORITY + 5;
 137
 138     @Reference
 139     protected RenderingQualityInteractor quality;
 140
 141     @Dependency
 142     protected TransformUtil          util;
 143
 144     @Dependency
 145     protected ElementPainter         diagramPainter;
 146
 147     @Dependency
 148     protected PointerInteractor      pi;
 149
 150     @Dependency
 151     protected PickContext            pickContext;
 152
 153     /**
 154      * Start element terminal of the connection. <code>null</code> if connection
 155      * was started from a flag or a branch point.
 156      *
 157      * The value is received by the constructor.
 158      */
 159     protected List<TerminalInfo>     startTerminals;
 160
 161     /**
 162      * Refers to any of the possible overlapping start terminals. The value is
 163      * taken from the first index of {@link #startTerminals} assuming that the
 164      * first one is the nearest. It is <code>null</code> if
 165      * {@link #startTerminals} is empty.
 166      */
 167     protected TerminalInfo           startTerminal;
 168
 169     protected TerminalInfo           startFlag;
 170
 171     /**
 172      * Starting position of the connection, received as an external argument.
 173      */
 174     protected final Point2D          startPos;
 175
 176     /**
 177      * <code>true</code> if this tool should create connection continuation
 178      * flags, <code>false</code> otherwise.
 179      */
 180     protected boolean                createFlags;
 181
 182     /**
 183      *
 184      */
 185     protected IElementClassProvider  elementClassProvider;
 186
 187     /**
 188      *
 189      */
 190     protected Deque<ControlPoint>    controlPoints         = new ArrayDeque<ControlPoint>();
 191
 192     /**
 193      * Contains <code>null</code> when a connection is started from a new flag
 194      * or one of the terminals in {@link #startTerminals} when a connection is
 195      * being created starting from a terminal or possibly a set of terminals.
 196      *
 197      * <p>
 198      * Note that this is different from {@link #startTerminal} which simply
 199      * represents the first element of {@link #startTerminals}.
 200      *
 201      * <p>
 202      * Only when this value and {@link #endTerminal} is properly set will a
 203      * connection be created between two element terminals.
 204      */
 205     protected TerminalInfo           selectedStartTerminal;
 206
 207     /**
 208      * Element terminal of connection end element. <code>null</code> if
 209      * connection cannot be ended where it is currently being attempted to end.
 210      */
 211     protected TerminalInfo           endTerminal;
 212
 213     /**
 214      * The latest connectability judgment from the active
 215      * {@link IConnectionAdvisor} should the connection happen between
 216      * {@link #selectedStartTerminal} and {@link #endTerminal}.
 217      */
 218     protected ConnectionJudgement    connectionJudgment;
 219
 220     /**
 221      * The latest connectability judgment from the active
 222      * {@link IConnectionAdvisor} should the connection happen between
 223      * {@link #selectedStartTerminal} and {@link #lastRouteGraphTarget}.
 224      */
 225     protected ConnectionJudgement    attachToConnectionJudgement;
 226
 227     /**
 228      * If non-null during connection drawing this field tells the direction
 229      * forced for the current branch point by the user through the UI commands
 230      * {@link Commands#ROTATE_ELEMENT_CCW} and
 231      * {@link Commands#ROTATE_ELEMENT_CW}.
 232      */
 233     private Direction                forcedBranchPointDirection;
 234
 235     /**
 236      * A temporary variable for use with
 237      * {@link TerminalTopology#getTerminals(IElement, Collection)}.
 238      */
 239     protected Collection<Terminal>   terminals             = new ArrayList<Terminal>();
 240
 241     /**
 242      * Previous mouse canvas position recorded by
 243      * {@link #processMouseMove(MouseMovedEvent)}.
 244      */
 245     protected Point2D                lastMouseCanvasPos    = new Point2D.Double();
 246
 247     /**
 248      * Set to true once {@link #processMouseMove(MouseMovedEvent)} has been
 249      * invoked at least once. This is used to tell whether to allow creation of
 250      * branch points or finising the connection in thin air. It will not be
 251      * allowed if the mouse has not moved at all since starting the connection.
 252      */
 253     protected boolean                mouseHasMoved         = false;
 254
 255     protected TerminalHoverStrategy  originalStrategy      = null;
 256
 257     protected TerminalHoverStrategy  terminalHoverStrategy = new TerminalHoverStrategy() {
 258         @Override
 259         public boolean highlightEnabled() {
 260             return !isEndingInFlag();
 261         }
 262
 263         @Override
 264         public boolean highlight(TerminalInfo ti) {
 265             boolean reflexive = isStartTerminal(ti.e, ti.t);
 266             if (reflexive && !allowReflexiveConnections())
 267                 return false;
 268
 269             return canConnect(ti.e, ti.t) != null;
 270         }
 271     };
 272
 273     protected final static Composite ALPHA_COMPOSITE       = AlphaComposite.getInstance(AlphaComposite.SRC_OVER, 0.75f);
 274
 275     /**
 276      * Root scene graph node for all visualization performed by this tool.
 277      */
 278     protected G2DParentNode          ghostNode;
 279
 280     /**
 281      * Indicates whether the connection is about to be ended into a new
 282      * flag/branchpoint or not.
 283      */
 284     protected TerminalInfo           endFlag;
 285
 286     protected G2DParentNode          endFlagNode;
 287
 288     private RouteGraphTarget         lastRouteGraphTarget;
 289
 290     /**
 291      * @param startTerminal
 292      * @param mouseId
 293      * @param startCanvasPos
 294      */
 295     public ConnectTool2(TerminalInfo startTerminal, int mouseId, Point2D startCanvasPos) {
 296         this(startTerminal == null ? Collections.<TerminalInfo> emptyList()
 297                 : Collections.singletonList(startTerminal),
 298                 mouseId,
 299                 startCanvasPos);
 300     }
 301
 302     /**
 303      * @param startTerminals
 304      * @param mouseId
 305      * @param startCanvasPos
 306      */
 307     public ConnectTool2(List<TerminalInfo> startTerminals, int mouseId, Point2D startCanvasPos) {
 308         super(mouseId);
 309
 310         if (startCanvasPos == null)
 311             throw new NullPointerException("null start position");
 312         if (startTerminals == null)
 313             throw new NullPointerException("null start terminals");
 314
 315         this.startPos = startCanvasPos;
 316         this.lastMouseCanvasPos.setLocation(startPos);
 317
 318         this.startTerminals = startTerminals;
 319         this.startTerminal = startTerminals.isEmpty() ? null : startTerminals.get(0);
 320     }
 321
 322     @Override
 323     public void addedToContext(ICanvasContext ctx) {
 324         super.addedToContext(ctx);
 325
 326         if (quality != null)
 327             quality.setStaticQuality(Quality.LOW);
 328
 329         // Force terminals to always be highlighted without pressing certain
 330         // keys or key combinations.
 331         originalStrategy = getHint(TerminalPainter.TERMINAL_HOVER_STRATEGY);
 332         setHint(TerminalPainter.TERMINAL_HOVER_STRATEGY, terminalHoverStrategy);
 333     }
 334
 335     @Override
 336     protected void onDiagramSet(IDiagram newDiagram, IDiagram oldDiagram) {
 337         if (newDiagram != null) {
 338             // Get IElementClassProvider
 339             ISynchronizationContext ctx = newDiagram.getHint(SynchronizationHints.CONTEXT);
 340             if (ctx != null) {
 341                 this.elementClassProvider = ctx.get(SynchronizationHints.ELEMENT_CLASS_PROVIDER);
 342             }
 343
 344             // See if flags should be created or not.
 345             this.createFlags = Boolean.TRUE.equals(newDiagram.getHint(DiagramHints.KEY_USE_CONNECTION_FLAGS));
 346             startConnection();
 347         }
 348     }
 349
 350     @Override
 351     public void removedFromContext(ICanvasContext ctx) {
 352         if (getHint(TerminalPainter.TERMINAL_HOVER_STRATEGY) == terminalHoverStrategy) {
 353             if (originalStrategy != null)
 354                 setHint(TerminalPainter.TERMINAL_HOVER_STRATEGY, originalStrategy);
 355             else
 356                 removeHint(TerminalPainter.TERMINAL_HOVER_STRATEGY);
 357         }
 358
 359         if (quality != null)
 360             quality.setStaticQuality(null);
 361
 362         super.removedFromContext(ctx);
 363     }
 364
 365     protected void startConnection() {
 366         Point2D startPos = (Point2D) this.startPos.clone();
 367         ISnapAdvisor snapAdvisor = getHint(DiagramHints.SNAP_ADVISOR);
 368         if (snapAdvisor != null)
 369             snapAdvisor.snap(startPos);
 370
 371         // Resolve the first element and terminal of the connection.
 372         ControlPoint start = new ControlPoint(startPos);
 373
 374         if (startTerminal != null) {
 375             assert ElementUtils.peekDiagram(startTerminal.e) == diagram;
 376             Point2D terminalPos = new Point2D.Double(startTerminal.posDia.getTranslateX(),
 377                     startTerminal.posDia.getTranslateY());
 378             start.setPosition(terminalPos).setAttachedToTerminal(startTerminal);
 379         } else {
 380             // Create TerminalInfo describing the flag to be created.
 381             if (createFlags) {
 382                 // This prevents connection creation from creating a branch
 383                 // point in place of this flag.
 384                 startFlag = createFlag(EdgeEnd.Begin);
 385                 start.setAttachedToTerminal(startFlag);
 386                 showElement(ghostNode, "startFlag", startFlag.e, startPos);
 387             }
 388         }
 389         controlPoints.add(start);
 390         controlPoints.add(new ControlPoint(startPos));
 391
 392         // Make sure that we are ending with a flag if ALT is pressed.
 393         // This makes the tool always start with a flag which can be quite
 394         // cumbersome and is therefore disabled. The current version will not
 395         // end the connection if the mouse has not moved at all.
 396         //if (keyUtil.isKeyPressed(java.awt.event.KeyEvent.VK_ALT)) {
 397         //    endWithoutTerminal(lastMouseCanvasPos, true);
 398         //}
 399     }
 400
 401     @SGInit
 402     public void initSG(G2DParentNode parent) {
 403         ghostNode = parent.addNode(G2DParentNode.class);
 404         ghostNode.setZIndex(PAINT_PRIORITY);
 405
 406         ShapeNode pathNode = ghostNode.getOrCreateNode("path", ShapeNode.class);
 407         pathNode.setColor(new Color(160, 0, 0));
 408         pathNode.setStroke(new BasicStroke(0.1f, BasicStroke.CAP_BUTT, BasicStroke.JOIN_MITER, 10,
 409                 new float[] { 0.5f, 0.2f }, 0));
 410         pathNode.setScaleStroke(false);
 411         pathNode.setZIndex(0);
 412
 413         G2DParentNode points = ghostNode.getOrCreateNode("points", G2DParentNode.class);
 414         points.setZIndex(1);
 415
 416         updateSG();
 417     }
 418
 419     private RouteTerminal addControlPoint(RouteGraph routeGraph, ControlPoint cp) {
 420         TerminalInfo ti = cp.getAttachedTerminal();
 421         if(ti != null && ti != startFlag && ti != endFlag) {
 422             Rectangle2D bounds = ElementUtils.getElementBoundsOnDiagram(ti.e, new Rectangle2D.Double());
 423             GeometryUtils.expandRectangle(bounds, 2);
 424             int allowedDirections = RouteGraphConnectionClass.shortestDirectionOutOfBounds(
 425                     ti.posDia.getTranslateX(), ti.posDia.getTranslateY(), bounds);
 426             return routeGraph.addTerminal(ti.posDia.getTranslateX(), ti.posDia.getTranslateY(),
 427                     bounds, allowedDirections, PlainLineEndStyle.INSTANCE);
 428         }
 429         else {
 430             double x = cp.getPosition().getX();
 431             double y = cp.getPosition().getY();
 432             int allowedDirections = 0xf;
 433             switch(cp.getDirection()) {
 434             case Horizontal: allowedDirections = 5; break;
 435             case Vertical: allowedDirections = 10; break;
 436             case Any: allowedDirections = 15; break;
 437             }
 438             return routeGraph.addTerminal(x, y, x, y, x, y, allowedDirections);
 439         }
 440     }
 441
 442     protected void updateSG() {
 443         if (controlPoints.size() != 2)
 444             return;
 445
 446         ControlPoint begin = controlPoints.getFirst();
 447         ControlPoint end = controlPoints.getLast();
 448
 449         RouteGraph routeGraph = new RouteGraph();
 450         RouteTerminal a = addControlPoint(routeGraph, begin);
 451         RouteTerminal b = addControlPoint(routeGraph, end);
 452         routeGraph.link(a, b);
 453
 454         Path2D path = routeGraph.getPath2D();
 455
 456         // Create scene graph to visualize the connection.
 457         ShapeNode pathNode = ghostNode.getOrCreateNode("path", ShapeNode.class);
 458         pathNode.setShape(path);
 459
 460         setDirty();
 461     }
 462
 463     private G2DParentNode showElement(G2DParentNode parent, String nodeId, IElement element, Point2D pos) {
 464         return showElement(parent, nodeId, element, AffineTransform.getTranslateInstance(pos.getX(), pos.getY()));
 465     }
 466
 467     private G2DParentNode showElement(G2DParentNode parent, String nodeId, IElement element, AffineTransform tr) {
 468         G2DParentNode elementParent = parent.getOrCreateNode(nodeId, G2DParentNode.class);
 469         elementParent.setTransform(tr);
 470         elementParent.removeNodes();
 471         for (SceneGraph sg : element.getElementClass().getItemsByClass(SceneGraph.class))
 472             sg.init(element, elementParent);
 473         return elementParent;
 474     }
 475
 476     @SGCleanup
 477     public void cleanupSG() {
 478         ghostNode.remove();
 479         ghostNode = null;
 480     }
 481
 482     @EventHandler(priority = 200)
 483     public boolean handleCommandEvents(CommandEvent ce) {
 484         if (ce.command.equals(Commands.CANCEL)) {
 485             setDirty();
 486             remove();
 487             return true;
 488         } else if (ce.command.equals(Commands.ROTATE_ELEMENT_CCW) || ce.command.equals(Commands.ROTATE_ELEMENT_CW)) {
 489             return rotateLastBranchPoint(ce.command.equals(Commands.ROTATE_ELEMENT_CW));
 490         }
 491         return false;
 492     }
 493
 494     @EventHandler(priority = PointerInteractor.TOOL_PRIORITY + 20)
 495     public boolean handleKeyEvents(KeyEvent ke) {
 496         if (ke instanceof KeyPressedEvent) {
 497             // Back-space, cancel prev bend
 498             if (ke.keyCode == java.awt.event.KeyEvent.VK_BACK_SPACE)
 499                 return cancelPreviousBend();
 500         }
 501
 502         if (ke.keyCode == java.awt.event.KeyEvent.VK_ALT) {
 503             if (createFlags) {
 504                 endWithoutTerminal(lastMouseCanvasPos, shouldEndWithFlag(ke instanceof KeyPressedEvent));
 505                 return true;
 506             }
 507         }
 508
 509         return false;
 510     }
 511
 512     @EventHandler(priority = PointerInteractor.TOOL_PRIORITY + 20)
 513     public boolean handleEvent(MouseEvent me) {
 514         // Only handle events for the connection-initiating mouse
 515         if (me.mouseId != mouseId)
 516             return false;
 517
 518         if (me instanceof MouseMovedEvent)
 519             return processMouseMove((MouseMovedEvent) me);
 520
 521         if (me instanceof MouseButtonPressedEvent)
 522             return processMouseButtonPress((MouseButtonPressedEvent) me);
 523
 524         // #7653: Support creating connections between terminals without lifting mouse button in between.
 525         if (me instanceof MouseButtonReleasedEvent)
 526             return processMouseButtonRelease((MouseButtonReleasedEvent) me);
 527
 528         return false;
 529     }
 530
 531     protected boolean processMouseMove(MouseMovedEvent me) {
 532         mouseHasMoved = true;
 533
 534         Point2D mouseControlPos = me.controlPosition;
 535         Point2D mouseCanvasPos = util.controlToCanvas(mouseControlPos, new Point2D.Double());
 536
 537         ISnapAdvisor snapAdvisor = getHint(DiagramHints.SNAP_ADVISOR);
 538         if (snapAdvisor != null)
 539             snapAdvisor.snap(mouseCanvasPos);
 540
 541         // Record last snapped canvas position of mouse.
 542         this.lastMouseCanvasPos.setLocation(mouseCanvasPos);
 543
 544         if (isEndingInFlag()) {
 545             endFlagNode.setTransform(AffineTransform.getTranslateInstance(mouseCanvasPos.getX(), mouseCanvasPos.getY()));
 546         }
 547
 548         List<TerminalInfo> tis = pi.pickTerminals(me.controlPosition);
 549         tis = TerminalUtil.findNearestOverlappingTerminals(tis);
 550         if (!tis.isEmpty() && !containsStartTerminal(tis)) {
 551             //System.out.println("end terminals (" + tis.size() + "):\n" + EString.implode(tis));
 552             for (TerminalInfo ti : tis) {
 553                 Pair<ConnectionJudgement, TerminalInfo> canConnect = canConnect(ti.e, ti.t);
 554                 if (canConnect != null) {
 555                     connectionJudgment = canConnect.first;
 556
 557                     if (!isEndingInFlag() || !TerminalUtil.isSameTerminal(ti, endTerminal)) {
 558                         if (canConnect.second != null) {
 559                             controlPoints.getFirst()
 560                             .setPosition(canConnect.second.posDia)
 561                             .setAttachedToTerminal(canConnect.second);
 562                         }
 563                         controlPoints.getLast()
 564                         .setPosition(ti.posDia)
 565                         .setAttachedToTerminal(ti);
 566
 567                         selectedStartTerminal = canConnect.second;
 568                         endTerminal = ti;
 569                     }
 570
 571                     // Make sure that we are ending with a flag if ALT is pressed
 572                     // and no end terminal is defined.
 573                     if (!endWithoutTerminal(lastMouseCanvasPos, shouldEndWithFlag(me)))
 574                         updateSG();
 575                     return false;
 576                 }
 577             }
 578         } else {
 579             RouteGraphTarget cp = RouteGraphConnectTool.pickRouteGraphConnection(
 580                     getContext(),
 581                     diagram,
 582                     pi.getCanvasPickShape(me.controlPosition),
 583                     pi.getPickDistance());
 584             if (cp != null) {
 585                 // Remove branch point highlight from previously picked route graph.
 586                 if (lastRouteGraphTarget != null && cp.getNode() != lastRouteGraphTarget.getNode())
 587                     cp.getNode().showBranchPoint(null);
 588                 lastRouteGraphTarget = cp;
 589
 590                 // Validate connection before visualizing connectability
 591                 Point2D isectPos = cp.getIntersectionPosition();
 592                 TerminalInfo ti = TerminalInfo.create(
 593                         isectPos,
 594                         cp.getElement(),
 595                         BranchPointTerminal.existingTerminal(
 596                                 isectPos,
 597                                 DirectionSet.ANY,
 598                                 BranchPointNode.SHAPE),
 599                         BranchPointNode.SHAPE);
 600                 Pair<ConnectionJudgement, TerminalInfo> canConnect = canConnect(ti.e, ti.t);
 601                 if (canConnect != null) {
 602                     attachToConnectionJudgement = canConnect.first;
 603                     controlPoints.getLast().setPosition(ti.posDia).setAttachedToTerminal(ti);
 604                     endTerminal = ti;
 605                     cp.getNode().showBranchPoint(isectPos);
 606                     if (!endWithoutTerminal(lastMouseCanvasPos, shouldEndWithFlag(me)))
 607                         updateSG();
 608                     return false;
 609                 }
 610             } else {
 611                 if (lastRouteGraphTarget != null) {
 612                     lastRouteGraphTarget.getNode().showBranchPoint(null);
 613                     lastRouteGraphTarget = null;
 614                 }
 615             }
 616         }
 617
 618         connectionJudgment = null;
 619         attachToConnectionJudgement = null;
 620         if (isEndTerminalDefined()) {
 621             // CASE: Mouse was previously on top of a valid terminal to end
 622             // the connection. Now the mouse has been moved where there is
 623             // no longer a terminal to connect to.
 624             //
 625             // => Disconnect the last edge segment from the previous
 626             // terminal, mark endElement/endTerminal non-existent
 627             // and connect the disconnected edge to a new branch point.
 628
 629             controlPoints.getLast()
 630             .setPosition(mouseCanvasPos)
 631             .setDirection(calculateCurrentBranchPointDirection())
 632             .setAttachedToTerminal(null);
 633
 634             endTerminal = null;
 635         } else {
 636             // CASE: Mouse was not previously on top of a valid ending
 637             // element terminal.
 638             //
 639             // => Move and re-orient last branch point.
 640
 641             controlPoints.getLast()
 642             .setPosition(mouseCanvasPos)
 643             .setDirection(calculateCurrentBranchPointDirection());
 644         }
 645
 646         // Make sure that we are ending with a flag if ALT is pressed and no end
 647         // terminal is defined.
 648         if (!endWithoutTerminal(lastMouseCanvasPos, shouldEndWithFlag(me)))
 649             updateSG();
 650
 651         return false;
 652     }
 653
 654     protected boolean processMouseButtonPress(MouseButtonPressedEvent e) {
 655         MouseButtonEvent me = e;
 656
 657         // Do nothing before the mouse has moved at least a little.
 658         // This prevents the user from ending the connection right where
 659         // it started.
 660         if (!mouseHasMoved)
 661             return true;
 662
 663         if (me.button == MouseEvent.LEFT_BUTTON) {
 664             Point2D mouseControlPos = me.controlPosition;
 665             Point2D mouseCanvasPos = util.getInverseTransform().transform(mouseControlPos, new Point2D.Double());
 666
 667             ISnapAdvisor snapAdvisor = getHint(DiagramHints.SNAP_ADVISOR);
 668             if (snapAdvisor != null)
 669                 snapAdvisor.snap(mouseCanvasPos);
 670
 671             if (tryEndConnection()) {
 672                 return true;
 673             } else {
 674                 // Finish connection in thin air only if the
 675                 // connection was started from a valid terminal.
 676                 if (me.hasAnyModifier(MouseEvent.ALT_MASK | MouseEvent.ALT_GRAPH_MASK) && !startTerminals.isEmpty()) {
 677                     Pair<ConnectionJudgement, TerminalInfo> pair = canConnect(null, null);
 678                     if (pair != null) {
 679                         connectionJudgment = (ConnectionJudgement) pair.first;
 680                         selectedStartTerminal = pair.second;
 681 //                        endFlag = createFlag(EdgeEnd.End);
 682 //                        controlPoints.getLast().setAttachedToTerminal(endFlag);
 683                         createConnection();
 684                         setDirty();
 685                         remove();
 686                     } else {
 687                         // Inform the user why connection couldn't be created.
 688                         String tmsg = terminalsToString(startTerminals);
 689                         ErrorLogger.defaultLogWarning("Can't resolve connection type for new connection when starting from one of the following terminals:\n" + tmsg, null);
 690                     }
 691                     return true;
 692                 } else if (routePointsAllowed()
 693                         && (me.stateMask & (MouseEvent.ALT_MASK | MouseEvent.SHIFT_MASK | MouseEvent.CTRL_MASK)) == 0) {
 694                     // Add new connection control point.
 695                     controlPoints.add(newControlPointWithCalculatedDirection(mouseCanvasPos));
 696                     resetForcedBranchPointDirection();
 697                     updateSG();
 698                 }
 699             }
 700
 701             // Eat the event to prevent other participants from doing
 702             // incompatible things while in this connection mode.
 703             return true;
 704         } else if (me.button == MouseEvent.RIGHT_BUTTON) {
 705             return cancelPreviousBend();
 706         }
 707
 708         return false;
 709     }
 710
 711     private int mouseLeftReleaseCount = 0;
 712
 713     protected boolean processMouseButtonRelease(MouseButtonReleasedEvent me) {
 714         if (me.button == MouseEvent.LEFT_BUTTON
 715                 && ++mouseLeftReleaseCount == 1) {
 716             return tryEndConnection();
 717         }
 718         return false;
 719     }
 720
 721     /**
 722      * @return <code>true</code> if connection was successfully ended
 723      */
 724     private boolean tryEndConnection() {
 725         if (isEndTerminalDefined() && connectionJudgment != null) {
 726             createConnection();
 727             remove();
 728             return true;
 729         } else if (lastRouteGraphTarget != null && attachToConnectionJudgement != null) {
 730             lastRouteGraphTarget.getNode().showBranchPoint(null);
 731             attachToConnection();
 732             remove();
 733             return true;
 734         }
 735         return false;
 736     }
 737
 738     private void attachToConnection() {
 739         ConnectionJudgement judgment = this.attachToConnectionJudgement;
 740         if (judgment == null) {
 741             ErrorLogger.defaultLogError("Cannot attach to connection, no judgment available on connection validity", null);
 742             return;
 743         }
 744
 745         ConnectionBuilder builder = new ConnectionBuilder(this.diagram);
 746         RouteGraph before = lastRouteGraphTarget.getNode().getRouteGraph();
 747         THashMap<Object, Object> copyMap = new THashMap<>();
 748         RouteGraph after = before.copy(copyMap);
 749
 750         RouteLine attachTo = (RouteLine) copyMap.get(lastRouteGraphTarget.getLine());
 751         after.makePersistent(attachTo);
 752         for (RouteLine line : after.getAllLines()) {
 753             if (!line.isTransient() && line.isHorizontal() == attachTo.isHorizontal()
 754                     && line.getPosition() == attachTo.getPosition()) {
 755                 attachTo = line;
 756                 break;
 757             }
 758         }
 759         RouteLine attachToLine = attachTo;
 760         RouteGraphDelta delta = new RouteGraphDelta(before, after);
 761
 762         Simantics.getSession().asyncRequest(new WriteRequest() {
 763             @Override
 764             public void perform(WriteGraph graph) throws DatabaseException {
 765                 graph.markUndoPoint();
 766                 Resource connection = ElementUtils.getObject(endTerminal.e);
 767                 if (!delta.isEmpty()) {
 768                     new RouteGraphConnection(graph, connection).synchronize(graph, before, after, delta);
 769                 }
 770                 Resource line = RouteGraphConnection.deserialize(graph, attachToLine.getData());
 771                 Deque<ControlPoint> cps = new ArrayDeque<>();
 772                 for (Iterator<ControlPoint> iterator = controlPoints.descendingIterator(); iterator.hasNext();)
 773                     cps.add(iterator.next());
 774                 builder.attachToRouteGraph(graph, judgment, connection, line, cps, startTerminal, FlagClass.Type.In);
 775             }
 776         }, parameter -> {
 777             if (parameter != null)
 778                 ExceptionUtils.logAndShowError(parameter);
 779         });
 780     }
 781
 782     protected boolean cancelPreviousBend() {
 783         if (!routePointsAllowed())
 784             return false;
 785
 786         // Just to make this code more comprehensible, prevent an editing
 787         // case that requires ugly code to work.
 788         if (isEndingInFlag())
 789             return true;
 790
 791         // If there are no real route points, cancel whole connection.
 792         if (controlPoints.size() <= 2) {
 793             setDirty();
 794             remove();
 795             return true;
 796         }
 797
 798         // Cancel last bend
 799         controlPoints.removeLast();
 800         controlPoints.getLast().setPosition(lastMouseCanvasPos);
 801         resetForcedBranchPointDirection();
 802
 803         updateSG();
 804         return true;
 805     }
 806
 807     /**
 808      * Rotates the last branch point in the created connection in either
 809      * clockwise or counter-clockwise direction as a response to a user
 810      * interaction.
 811      *
 812      * <p>
 813      * At the same time it use {@link #forcedBranchPointDirection} to mark the
 814      * current last branch point to be forcefully oriented according to the
 815      * users wishes instead of calculating a default value for the orientation
 816      * from the routed connection path. See
 817      * {@link #calculateCurrentBranchPointDirection()} for more information on
 818      * this.
 819      *
 820      * <p>
 821      * The logic of this method goes as follows:
 822      * <ul>
 823      * <li>Calculate the current branch point direction</li>
 824      * <li>If the branch point direction is currently user selected (
 825      * {@link #forcedBranchPointDirection}</li>
 826      * <li></li>
 827      * <li></li>
 828      * </ul>
 829      *
 830      * @param clockwise
 831      * @return <code>true</code> if the rotation was successful
 832      */
 833     protected boolean rotateLastBranchPoint(boolean clockwise) {
 834         Direction oldDir = calculateCurrentBranchPointDirection();
 835
 836         if (forcedBranchPointDirection == null) {
 837             forcedBranchPointDirection = oldDir.toggleDetermined();
 838         } else {
 839             forcedBranchPointDirection = clockwise ? oldDir.cycleNext() : oldDir.cyclePrevious();
 840         }
 841
 842         controlPoints.getLast().setDirection(forcedBranchPointDirection);
 843
 844         updateSG();
 845
 846         return true;
 847     }
 848
 849     /**
 850      * Set preferred direction for a branch/route point element.
 851      *
 852      * @param branchPoint the element to set the direction for
 853      * @param direction the direction to set
 854      * @return
 855      */
 856     protected void setDirection(IElement branchPoint, Direction direction) {
 857         branchPoint.getElementClass().getSingleItem(BranchPoint.class).setDirectionPreference(branchPoint, direction);
 858     }
 859
 860     protected Direction forcedBranchPointDirection() {
 861         return forcedBranchPointDirection;
 862     }
 863
 864     protected void resetForcedBranchPointDirection() {
 865         forcedBranchPointDirection = null;
 866     }
 867
 868     protected void forceBranchPointDirection(Direction direction) {
 869         forcedBranchPointDirection = direction;
 870     }
 871
 872     /**
 873      * @return
 874      */
 875     protected Direction calculateCurrentBranchPointDirection() {
 876         // If this is not the first branch point, toggle direction compared to
 877         // last.
 878         if (forcedBranchPointDirection != null)
 879             return forcedBranchPointDirection;
 880
 881         if (controlPoints.size() > 2) {
 882             // This is not the first edge segment, toggle route point
 883             // directions.
 884             Iterator<ControlPoint> it = controlPoints.descendingIterator();
 885             it.next();
 886             ControlPoint secondLastCp = it.next();
 887
 888             Direction dir = secondLastCp.getDirection();
 889             switch (dir) {
 890                 case Horizontal:
 891                     return Direction.Vertical;
 892                 case Vertical:
 893                     return Direction.Horizontal;
 894                 case Any:
 895             }
 896         }
 897
 898         // If this is the first branch point, calculate based on edge segment
 899         // angle.
 900         if (controlPoints.size() > 1) {
 901             Iterator<ControlPoint> it = controlPoints.descendingIterator();
 902             ControlPoint last = it.next();
 903             ControlPoint secondLast = it.next();
 904
 905             double angle = Math.atan2(Math.abs(last.getPosition().getY() - secondLast.getPosition().getY()),
 906                     Math.abs(last.getPosition().getX() - secondLast.getPosition().getX()));
 907
 908             if (angle >= 0 && angle < Math.PI / 4) {
 909                 return Direction.Horizontal;
 910             } else if (angle > Math.PI / 4 && angle <= Math.PI / 2) {
 911                 return Direction.Vertical;
 912             }
 913         }
 914
 915         return Direction.Any;
 916     }
 917
 918     protected boolean isEndingInFlag() {
 919         return endFlag != null;
 920     }
 921
 922     /**
 923      * @param mousePos
 924      * @param altDown
 925      * @return <code>true</code> if updateSG was executed, <code>false</code>
 926      *         otherwise
 927      */
 928     protected boolean endWithoutTerminal(Point2D mousePos, boolean altDown) {
 929         // Just go with branch points if flags are not allowed.
 930         if (!createFlags)
 931             return false;
 932
 933         boolean endTerminalDefined = isEndTerminalDefined();
 934
 935         if (altDown) {
 936             if (!isEndingInFlag()) {
 937                 endFlag = createFlag(EdgeEnd.End);
 938                 endFlagNode = showElement(ghostNode, "endFlag", endFlag.e, mousePos);
 939                 controlPoints.getLast()
 940                 .setDirection(calculateCurrentBranchPointDirection())
 941                 .setAttachedToTerminal(endFlag);
 942
 943                 // TerminalPainter must refresh
 944                 setHint(TerminalPainter.TERMINAL_HOVER_STRATEGY, terminalHoverStrategy);
 945
 946                 updateSG();
 947                 return true;
 948             }
 949         } else {
 950             if (isEndingInFlag()) {
 951                 // Currently ending with flag but ALT is no longer down
 952                 // so that flag must be removed.
 953                 endFlag = null;
 954                 endFlagNode.remove();
 955                 endFlagNode = null;
 956
 957                 ControlPoint cp = controlPoints.getLast();
 958                 cp.setDirection(calculateCurrentBranchPointDirection())
 959                 .setAttachedToTerminal(endTerminal);
 960
 961                 if (endTerminalDefined) {
 962                     cp.setPosition(endTerminal.posDia);
 963                 } else {
 964                     cp.setPosition(mousePos);
 965                 }
 966
 967                 // Force TerminalPainter refresh
 968                 setHint(TerminalPainter.TERMINAL_HOVER_STRATEGY, terminalHoverStrategy);
 969
 970                 updateSG();
 971                 return true;
 972             }
 973         }
 974         return false;
 975     }
 976
 977     protected void createConnection() {
 978         createConnection(
 979                 this.selectedStartTerminal,
 980                 this.endTerminal,
 981                 this.connectionJudgment,
 982                 this.controlPoints);
 983     }
 984
 985     protected void createConnection(
 986             final TerminalInfo startTerminal,
 987             final TerminalInfo endTerminal,
 988             final ConnectionJudgement judgement,
 989             final Deque<ControlPoint> controlPoints)
 990     {
 991         TimeLogger.resetTimeAndLog(getClass(), "createConnection");
 992         if (judgement == null) {
 993             // Inform the user why connection couldn't be created.
 994             String tmsg = terminalsToString(Arrays.asList(startTerminal, endTerminal));
 995             ErrorLogger.defaultLogError("Cannot create connection, no judgment available on connection validity when connecting the terminals:\n" + tmsg, null);
 996             return;
 997         }
 998
 999         final ConnectionBuilder builder = new ConnectionBuilder(this.diagram);
1000
1001         Simantics.getSession().asyncRequest(new WriteRequest() {
1002             @Override
1003             public void perform(WriteGraph graph) throws DatabaseException {
1004                 builder.create(graph, judgement, controlPoints, startTerminal, endTerminal);
1005             }
1006         }, parameter -> {
1007             if (parameter != null)
1008                 ExceptionUtils.logAndShowError(parameter);
1009         });
1010     }
1011
1012     /**
1013      * @param canvasPos
1014      * @return
1015      */
1016     protected ControlPoint newControlPointWithCalculatedDirection(Point2D canvasPos) {
1017         return new ControlPoint(canvasPos, calculateCurrentBranchPointDirection());
1018     }
1019
1020     /**
1021      * @param e
1022      * @param t
1023      * @return <code>true</code> if the specified element terminal matches any
1024      *         TerminalInfo in {@link #startTerminals}
1025      */
1026     protected boolean isStartTerminal(IElement e, Terminal t) {
1027         if (startTerminal == null)
1028             return false;
1029         for (TerminalInfo st : startTerminals) {
1030             if (st.e == e && st.t == t) {
1031                 return true;
1032             }
1033         }
1034         return false;
1035     }
1036
1037     /**
1038      * @param e
1039      * @param t
1040      * @return <code>true</code> if the specified element terminal matches any
1041      *         TerminalInfo in {@link #startTerminals}
1042      */
1043     protected boolean containsStartTerminal(List<TerminalInfo> tis) {
1044         if (startTerminal == null)
1045             return false;
1046         for (TerminalInfo st : startTerminals) {
1047             for (TerminalInfo et : tis) {
1048                 if (st.e == et.e && st.t == et.t) {
1049                     return true;
1050                 }
1051             }
1052         }
1053         return false;
1054     }
1055
1056     protected static FlagClass.Type endToFlagType(EdgeEnd end) {
1057         switch (end) {
1058             case Begin:
1059                 return FlagClass.Type.In;
1060             case End:
1061                 return FlagClass.Type.Out;
1062             default:
1063                 throw new IllegalArgumentException("unrecognized edge end: " + end);
1064         }
1065     }
1066
1067     protected TerminalInfo createFlag(EdgeEnd connectionEnd) {
1068         ElementClass flagClass = elementClassProvider.get(ElementClasses.FLAG);
1069         IElement e = Element.spawnNew(flagClass);
1070
1071         e.setHint(FlagClass.KEY_FLAG_TYPE, endToFlagType(connectionEnd));
1072         e.setHint(FlagClass.KEY_FLAG_MODE, FlagClass.Mode.Internal);
1073
1074         TerminalInfo ti = new TerminalInfo();
1075         ti.e = e;
1076         ti.t = ElementUtils.getSingleTerminal(e);
1077         ti.posElem = TerminalUtil.getTerminalPosOnElement(e, ti.t);
1078         ti.posDia = TerminalUtil.getTerminalPosOnDiagram(e, ti.t);
1079
1080         return ti;
1081     }
1082
1083     protected boolean shouldEndWithFlag(MouseEvent me) {
1084         return shouldEndWithFlag( me.hasAnyModifier(MouseEvent.ALT_MASK | MouseEvent.ALT_GRAPH_MASK) );
1085     }
1086
1087     protected boolean shouldEndWithFlag(boolean altPressed) {
1088         return altPressed && !isEndTerminalDefined() && createFlags && startFlag == null;
1089     }
1090
1091     protected boolean isEndTerminalDefined() {
1092         return endTerminal != null;
1093     }
1094
1095     protected boolean isFlagTerminal(TerminalInfo ti) {
1096         return ti.e.getElementClass().containsClass(FlagHandler.class);
1097     }
1098
1099     protected boolean allowReflexiveConnections() {
1100         return false;
1101     }
1102
1103     protected boolean routePointsAllowed() {
1104         return Boolean.TRUE.equals(diagram.getHint(DiagramHints.KEY_ALLOW_ROUTE_POINTS));
1105     }
1106
1107     /**
1108      * @param endElement
1109      * @param endTerminal
1110      * @return
1111      */
1112     @SuppressWarnings("unchecked")
1113     protected final Pair<ConnectionJudgement, TerminalInfo> canConnect(IElement endElement, Terminal endTerminal) {
1114         IConnectionAdvisor advisor = diagram.getHint(DiagramHints.CONNECTION_ADVISOR);
1115         Object judgement = canConnect(advisor, endElement, endTerminal);
1116         if (judgement == null)
1117             return null;
1118         if (judgement instanceof Pair<?, ?>)
1119             return (Pair<ConnectionJudgement, TerminalInfo>) judgement;
1120         return Pair.<ConnectionJudgement, TerminalInfo>make((ConnectionJudgement) judgement, startTerminal);
1121     }
1122
1123     protected Object canConnect(IConnectionAdvisor advisor, IElement endElement, Terminal endTerminal) {
1124         if (advisor == null)
1125             return Pair.make(ConnectionJudgement.CANBEMADELEGAL, startTerminal);
1126         if (startTerminals.isEmpty()) {
1127             ConnectionJudgement obj = (ConnectionJudgement) advisor.canBeConnected(null, null, null, endElement, endTerminal);
1128             return obj != null ? Pair.<ConnectionJudgement, TerminalInfo>make(obj, null) : null;
1129         }
1130         for (TerminalInfo st : startTerminals) {
1131             ConnectionJudgement obj = (ConnectionJudgement) advisor.canBeConnected(null, st.e, st.t, endElement, endTerminal);
1132             if (obj != null) {
1133                 return Pair.make(obj, st);
1134             }
1135         }
1136         return null;
1137     }
1138
1139     /**
1140      * For generating debugging information of what was attempted by the user
1141      * when a connection couldn't be created.
1142      *
1143      * @param ts
1144      * @return
1145      */
1146     private String terminalsToString(final Iterable<TerminalInfo> ts) {
1147         try {
1148             return Simantics.sync(new UniqueRead<String>() {
1149                 @Override
1150                 public String perform(ReadGraph graph) throws DatabaseException {
1151                     DiagramResource DIA = DiagramResource.getInstance(graph);
1152                     ModelingResources MOD = ModelingResources.getInstance(graph);
1153                     StringBuilder sb = new StringBuilder();
1154                     boolean first = true;
1155                     for (TerminalInfo ti : ts) {
1156                         if (!first)
1157                             sb.append("\n");
1158                         first = false;
1159                         sb.append("element ");
1160                         Object o = ElementUtils.getObject(ti.e);
1161                         if (o instanceof Resource) {
1162                             Resource er = (Resource) o;
1163                             Resource cer = graph.getPossibleObject(er, MOD.ElementToComponent);
1164                             Resource r = cer != null ? cer : er;
1165                             sb.append(NameUtils.getSafeName(graph, r)).append(" : ");
1166                             for (Resource type : graph.getPrincipalTypes(r)) {
1167                                 sb.append(NameUtils.getSafeName(graph, type, true));
1168                             }
1169                         } else {
1170                             sb.append(ti.e.toString());
1171                         }
1172                         sb.append(", terminal ");
1173                         if (ti.t instanceof ResourceTerminal) {
1174                             Resource tr = ((ResourceTerminal) ti.t).getResource();
1175                             Resource cp = graph.getPossibleObject(tr, DIA.HasConnectionPoint);
1176                             Resource r = cp != null ? cp : tr;
1177                             sb.append(NameUtils.getSafeName(graph, r, true));
1178                         } else {
1179                             sb.append(ti.t.toString());
1180                         }
1181                     }
1182                     return sb.toString();
1183                 }
1184             });
1185         } catch (DatabaseException e) {
1186             return e.getMessage();
1187         }
1188     }
1189
1190 }