我正在尝试使用此代码来更改连接到在 jgraphx 中单击的顶点的某些顶点的不透明度，并且当您单击顶点之外的某个位置时，它将重新更改不透明度。单击顶点时，将查询其值/字符串，并将连接到它的所有对象添加到新对象列表中。然后我处理此对象列表以选择要突出显示的内容和不突出显示的内容。但是我不断收到错误并且无法修复它。据我检查，我没有任何空对象。如果有人可以提供帮助，将不胜感激。
错误指的是以下行：
graph.getView().getState(myCell).getStyle().put(mxConstants.STYLE_OPACITY, OPACITY_HL);
这是代码：
public void MassCellHighlight() {
int OPACITY_PALE = 15;
int OPACITY_HL = 100;
graphComponent.getGraphControl().addMouseListener(new MouseAdapter() {
public void mouseReleased (MouseEvent e1) {
if (e1.getButton() == 1 && e1.getClickCount() == 1) {
long x = e1.getX();
long y = e1.getY();
Object cell = graphComponent.getCellAt((int) x, (int)y);
String usecell = graph.convertValueToString(cell);
PropertyConfigurator.configure("\\jena-log4j.properties");
OntModel model = ModelFactory.createOntologyModel(OntModelSpec.OWL_MEM);
FileManager.get().readModel( model, "file" );
String queryString =
"PREFIX rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#> " +
"PREFIX owl: <http://www.w3.org/2002/07/owl#> " +
"PREFIX xsd: <http://www.w3.org/2001/XMLSchema#> " +
"PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#> " +
"PREFIX bi: <#> " +
" SELECT ?Path " +
" WHERE { bi:"+usecell+" bi:can_lead_to ?Path } " ;
Query query = QueryFactory.create(queryString);
QueryExecution qe= QueryExecutionFactory.create(query, model);
ResultSet resultset = qe.execSelect();
ResultSet results = ResultSetFactory.copyResults(resultset);
List<Object> values = new ArrayList<Object>();
while ( results.hasNext() ) {
values.add( results.next().get( "Path" ));
}
String s = values.toString();
Pattern p = Pattern.compile("(?<=#)([^,]*)(?=(,|\\]))");
Matcher m = p.matcher(s);
List<String> listhl = new ArrayList<String>() ;
while (m.find()) {
listhl.add(m.group(1));
}
listhl.add(usecell);
List<Object> objectlist = new ArrayList<Object>(listhl);
System.out.println(objectlist);
Object[] allCells = mxGraphModel.getChildren(graph.getModel(), graph.getDefaultParent());
if (cell != null) {
if (graph.getModel().isVertex(cell)) {
for( Object myCell : objectlist) {
graph.getView().getState(myCell).getStyle().put(mxConstants.STYLE_OPACITY, OPACITY_HL);
graph.getView().getState(myCell).getStyle().put(mxConstants.STYLE_TEXT_OPACITY, OPACITY_HL);
}
for ( Object myCell: allCells) {
graph.getView().getState(myCell).getStyle().put(mxConstants.STYLE_OPACITY, OPACITY_PALE);
graph.getView().getState(myCell).getStyle().put(mxConstants.STYLE_TEXT_OPACITY, OPACITY_PALE);
}
}else {
for( Object myCell: allCells) {
graph.getView().getState(myCell).getStyle().put(mxConstants.STYLE_OPACITY, OPACITY_HL);
graph.getView().getState(myCell).getStyle().put(mxConstants.STYLE_TEXT_OPACITY, OPACITY_HL);
}
}
mxRectangle bounds = graph.getBoundsForCells(allCells, true, true, true);
graph.repaint( bounds);
}
}
}
});
}
错误：
Exception in thread "AWT-EventQueue-0" java.lang.NullPointerException
at GUIquery$14.mouseReleased(GUIquery.java:1087)
at java.awt.AWTEventMulticaster.mouseReleased(Unknown Source)
at java.awt.Component.processMouseEvent(Unknown Source)
at javax.swing.JComponent.processMouseEvent(Unknown Source)
at java.awt.Component.processEvent(Unknown Source)
at java.awt.Container.processEvent(Unknown Source)
at java.awt.Component.dispatchEventImpl(Unknown Source)
at java.awt.Container.dispatchEventImpl(Unknown Source)
at java.awt.Component.dispatchEvent(Unknown Source)
at java.awt.LightweightDispatcher.retargetMouseEvent(Unknown Source)
at java.awt.LightweightDispatcher.processMouseEvent(Unknown Source)
at java.awt.LightweightDispatcher.dispatchEvent(Unknown Source)
at java.awt.Container.dispatchEventImpl(Unknown Source)
at java.awt.Window.dispatchEventImpl(Unknown Source)
at java.awt.Component.dispatchEvent(Unknown Source)
at java.awt.EventQueue.dispatchEventImpl(Unknown Source)
at java.awt.EventQueue.access$200(Unknown Source)
at java.awt.EventQueue$3.run(Unknown Source)
at java.awt.EventQueue$3.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at java.security.ProtectionDomain$1.doIntersectionPrivilege(Unknown Source)
at java.security.ProtectionDomain$1.doIntersectionPrivilege(Unknown Source)
at java.awt.EventQueue$4.run(Unknown Source)
at java.awt.EventQueue$4.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at java.security.ProtectionDomain$1.doIntersectionPrivilege(Unknown Source)
at java.awt.EventQueue.dispatchEvent(Unknown Source)
at java.awt.EventDispatchThread.pumpOneEventForFilters(Unknown Source)
at java.awt.EventDispatchThread.pumpEventsForFilter(Unknown Source)
at java.awt.EventDispatchThread.pumpEventsForHierarchy(Unknown Source)
at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
at java.awt.EventDispatchThread.run(Unknown Source)
当我使用仅突出显示父顶点的子级的代码时，它可以正常工作。我只需要扩展它，以便突出显示更多单元格，具体取决于查询中出现的对象列表：
public void CellHighlight() {
graphComponent.getGraphControl().addMouseListener(new MouseAdapter() {
public void mouseReleased (MouseEvent e1) {
if (e1.getButton() == 1 && e1.getClickCount() == 2) {
final Object selectedCell = graphComponent.getCellAt(e1.getX(), e1.getY());
Object[] allCells = mxGraphModel.getChildren(graph.getModel(), graph.getDefaultParent());
if (selectedCell != null) {
if (graph.getModel().isVertex( selectedCell)) {
for( Object myCell: allCells) {
graph.getView().getState(myCell).getStyle().put(mxConstants.STYLE_OPACITY, OPACITY_PALE);
graph.getView().getState(myCell).getStyle().put(mxConstants.STYLE_TEXT_OPACITY, OPACITY_PALE);
}
List<Object> cellList = new ArrayList<Object>();
cellList.add(selectedCell);
Object[] outgoingEdges = mxGraphModel.getOutgoingEdges( graph.getModel(), selectedCell);
for( Object edge: outgoingEdges) {
cellList.add( graph.getModel().getTerminal( edge, false));
}
cellList.addAll( Arrays.asList(outgoingEdges));
for( Object myCell: cellList) {
graph.getView().getState(myCell).getStyle().put(mxConstants.STYLE_OPACITY, OPACITY_HL);
graph.getView().getState(myCell).getStyle().put(mxConstants.STYLE_TEXT_OPACITY, OPACITY_HL);
}
} else {
for( Object myCell: allCells) {
graph.getView().getState(myCell).getStyle().put(mxConstants.STYLE_OPACITY, OPACITY_HL);
graph.getView().getState(myCell).getStyle().put(mxConstants.STYLE_TEXT_OPACITY, OPACITY_HL);
}
}
mxRectangle bounds = graph.getBoundsForCells(allCells, true, true, true);
graph.repaint( bounds);
}
}
}
});
}