eu.etaxonomy.taxeditor.navigation/src/main/java/eu/etaxonomy/taxeditor/navigation/navigator/TaxonNavigatorDnDService.java

   1 package eu.etaxonomy.taxeditor.navigation.navigator;
   2
   3 import java.util.Arrays;
   4 import java.util.Comparator;
   5 import java.util.HashMap;
   6 import java.util.Iterator;
   7 import java.util.LinkedHashSet;
   8 import java.util.Map;
   9 import java.util.Set;
  10
  11 import org.eclipse.jface.util.LocalSelectionTransfer;
  12 import org.eclipse.jface.viewers.IStructuredSelection;
  13 import org.eclipse.swt.dnd.TransferData;
  14 import org.eclipse.ui.internal.navigator.dnd.CommonDropAdapterDescriptor;
  15 import org.eclipse.ui.internal.navigator.dnd.CommonDropDescriptorManager;
  16 import org.eclipse.ui.internal.navigator.extensions.CommonDragAssistantDescriptor;
  17 import org.eclipse.ui.internal.navigator.extensions.NavigatorViewerDescriptor;
  18 import org.eclipse.ui.navigator.CommonDragAdapterAssistant;
  19 import org.eclipse.ui.navigator.CommonDropAdapter;
  20 import org.eclipse.ui.navigator.CommonDropAdapterAssistant;
  21 import org.eclipse.ui.navigator.INavigatorContentService;
  22 import org.eclipse.ui.navigator.INavigatorDnDService;
  23
  24 import eu.etaxonomy.taxeditor.navigation.navigator.dnd.TaxonNavigatorDragAdapterAssistant;
  25
  26 public class TaxonNavigatorDnDService implements INavigatorDnDService {
  27         private static final CommonDropAdapterAssistant[] NO_ASSISTANTS = new CommonDropAdapterAssistant[0];
  28
  29         private INavigatorContentService contentService;
  30
  31         private TaxonNavigatorDragAdapterAssistant[] dragAssistants;
  32
  33         private TreeNodeDropAdapter dropAdapter;
  34
  35         private final Map dropAssistants = new HashMap();
  36
  37         public TaxonNavigatorDnDService(INavigatorContentService contentService){
  38                 this.contentService = contentService;
  39         }
  40
  41
  42         @Override
  43         public CommonDragAdapterAssistant[] getCommonDragAssistants() {
  44
  45                 return dragAssistants;
  46         }
  47
  48         @Override
  49         public void bindDragAssistant(CommonDragAdapterAssistant anAssistant) {
  50                 if(dragAssistants == null)
  51                         initializeDragAssistants();
  52                 TaxonNavigatorDragAdapterAssistant[] newDragAssistants = new TaxonNavigatorDragAdapterAssistant[dragAssistants.length + 1];
  53                 System.arraycopy(dragAssistants, 0, newDragAssistants, 0, dragAssistants.length);
  54                 newDragAssistants[dragAssistants.length] = (TaxonNavigatorDragAdapterAssistant) anAssistant;
  55                 dragAssistants = newDragAssistants;
  56
  57         }
  58
  59         private void initializeDragAssistants() {
  60                 int i = 0;
  61                 Set dragDescriptors = ((NavigatorViewerDescriptor) contentService
  62                                 .getViewerDescriptor()).getDragAssistants();
  63                 dragAssistants = new TaxonNavigatorDragAdapterAssistant[dragDescriptors
  64                                 .size()];
  65                 for (Iterator iter = dragDescriptors.iterator(); iter.hasNext();) {
  66                         CommonDragAssistantDescriptor descriptor = (CommonDragAssistantDescriptor) iter
  67                                         .next();
  68                         dragAssistants[i++] = (TaxonNavigatorDragAdapterAssistant) descriptor.createDragAssistant();
  69                 }
  70         }
  71
  72         @Override
  73         public CommonDropAdapterAssistant[] findCommonDropAdapterAssistants(
  74                         Object aDropTarget, TransferData aTransferType) {
  75                 CommonDropAdapterDescriptor[] descriptors = CommonDropDescriptorManager
  76                                 .getInstance().findCommonDropAdapterAssistants(aDropTarget,
  77                                                 contentService);
  78
  79                 if (descriptors.length == 0) {
  80                         return NO_ASSISTANTS;
  81                 }
  82
  83                 if (LocalSelectionTransfer.getTransfer().isSupportedType(aTransferType)
  84                                                 && LocalSelectionTransfer.getTransfer().getSelection() instanceof IStructuredSelection) {
  85                         return getAssistantsBySelection(descriptors, (IStructuredSelection) LocalSelectionTransfer.getTransfer().getSelection());
  86                 }
  87                 return getAssistantsByTransferData(descriptors, aTransferType);
  88         }
  89
  90         private CommonDropAdapterAssistant[] getAssistantsByTransferData(
  91                         CommonDropAdapterDescriptor[] descriptors,
  92                         TransferData aTransferType) {
  93
  94                 Set assistants = new LinkedHashSet();
  95                 for (int i = 0; i < descriptors.length; i++) {
  96                         CommonDropAdapterAssistant asst = getAssistant(descriptors[i]);
  97                         if (asst.isSupportedType(aTransferType)) {
  98                                 assistants.add(asst);
  99                         }
 100                 }
 101                 return sortAssistants((CommonDropAdapterAssistant[]) assistants
 102                                 .toArray(new CommonDropAdapterAssistant[assistants.size()]));
 103
 104         }
 105
 106         private CommonDropAdapterAssistant[] getAssistantsBySelection(
 107                         CommonDropAdapterDescriptor[] descriptors, IStructuredSelection aSelection) {
 108
 109                 Set assistants = new LinkedHashSet();
 110
 111                 for (int i = 0; i < descriptors.length; i++) {
 112                         if(descriptors[i].areDragElementsSupported(aSelection)) {
 113                                 assistants.add(getAssistant(descriptors[i]));
 114                         }
 115                 }
 116
 117                 return sortAssistants((CommonDropAdapterAssistant[]) assistants
 118                                 .toArray(new CommonDropAdapterAssistant[assistants.size()]));
 119         }
 120
 121         private CommonDropAdapterAssistant getAssistant(
 122                         CommonDropAdapterDescriptor descriptor) {
 123                 TreeNodeDropAdapterAssistant asst = (TreeNodeDropAdapterAssistant) dropAssistants
 124                                 .get(descriptor);
 125                 if (asst != null) {
 126                         return asst;
 127                 }
 128                 synchronized (dropAssistants) {
 129                         asst = (TreeNodeDropAdapterAssistant) dropAssistants.get(descriptor);
 130                         if (asst == null) {
 131                                 dropAssistants.put(descriptor, (asst = (TreeNodeDropAdapterAssistant) descriptor
 132                                                 .createDropAssistant()));
 133                                 asst.init(contentService);
 134                                 //asst.setCommonDropAdapter(dropAdapter);
 135                         }
 136                 }
 137                 return asst;
 138         }
 139
 140
 141         private CommonDropAdapterAssistant[] sortAssistants(CommonDropAdapterAssistant[] array) {
 142                 Arrays.sort(array, new Comparator() {
 143                         public int compare(Object arg0, Object arg1) {
 144                                 CommonDropAdapterAssistant a = (CommonDropAdapterAssistant) arg0;
 145                                 CommonDropAdapterAssistant b = (CommonDropAdapterAssistant) arg1;
 146                                 // This is to ensure that the navigator resources drop assistant will
 147                                 // always be first on the list of drop assistant, if a conflict ever
 148                                 // occurs.
 149                                 String id = "org.eclipse.ui.navigator.resources."; //$NON-NLS-1$
 150                                 if (a.getClass().getName().startsWith(id))
 151                                         return -1;
 152                                 if (b.getClass().getName().startsWith(id))
 153                                         return 1;
 154                                 return a.getClass().getName().compareTo(b.getClass().getName());
 155                         }
 156                 });
 157                 return array;
 158         }
 159
 160         @Override
 161         public CommonDropAdapterAssistant[] findCommonDropAdapterAssistants(
 162                         Object aDropTarget, IStructuredSelection theDragSelection) {
 163                 // TODO Auto-generated method stub
 164                 return null;
 165         }
 166
 167         public void setDropAdaptor(TreeNodeDropAdapter da) {
 168                 dropAdapter = da;
 169         }
 170 }