eu.etaxonomy.taxeditor.store/src/main/java/eu/etaxonomy/taxeditor/model/TaxonTransfer.java

   1 package eu.etaxonomy.taxeditor.model;
   2
   3 import org.eclipse.swt.dnd.ByteArrayTransfer;
   4 import org.eclipse.swt.dnd.TransferData;
   5
   6 import eu.etaxonomy.cdm.model.taxon.TaxonBase;
   7
   8 /**
   9  * For drag and drop - a drag widget with this transfer type can only be dropped onto
  10  *  a drop widget with the same type.
  11  *
  12  * @author p.ciardelli
  13  * @version $Id: $
  14  */
  15 public class TaxonTransfer extends ByteArrayTransfer {
  16
  17         private static final String TAXONTYPENAME = "taxon_type";
  18         private static final int TAXONTYPEID = registerType (TAXONTYPENAME);
  19         private static final TaxonTransfer INSTANCE = new TaxonTransfer();
  20
  21         /*
  22          * The object associated with this transfer event
  23          */
  24         private TaxonBase<?> taxonBase;
  25
  26         /*
  27          * Returns the singleton
  28          */
  29         /**
  30          * <p>getInstance</p>
  31          *
  32          * @return a {@link eu.etaxonomy.taxeditor.model.TaxonTransfer} object.
  33          */
  34         public static TaxonTransfer getInstance() {
  35                 return INSTANCE;
  36         }
  37         /*
  38          * Set transfer data for local use
  39          */
  40         /**
  41          * <p>setTaxon</p>
  42          *
  43          * @param taxon a {@link eu.etaxonomy.cdm.model.taxon.TaxonBase} object.
  44          */
  45         public void setTaxon(TaxonBase<?> taxon) {
  46                 this.taxonBase = taxon;
  47         }
  48         /*
  49          * Returns the local transfer data
  50          */
  51         /**
  52          * <p>getTaxon</p>
  53          *
  54          * @return a {@link eu.etaxonomy.cdm.model.taxon.TaxonBase} object.
  55          */
  56         public TaxonBase<?> getTaxon() {
  57                 return taxonBase;
  58         }
  59
  60         /*
  61          * The type ID is used to identify this transfer
  62          */
  63         /** {@inheritDoc} */
  64         @Override
  65         protected int[] getTypeIds() {
  66                 return new int[] { TAXONTYPEID };
  67         }
  68
  69         /** {@inheritDoc} */
  70         @Override
  71         protected String[] getTypeNames() {
  72                 return new String[] { TAXONTYPENAME } ;
  73         }
  74
  75         /** {@inheritDoc} */
  76         @Override
  77         protected void javaToNative(Object object, TransferData transferData) {
  78                 // No encoding needed since this is a hardcoded string read and written
  79                 // in the same process.
  80                 // See nativeToJava below
  81                 byte[] check = TAXONTYPENAME.getBytes();
  82                 super.javaToNative(check, transferData);
  83         }
  84
  85         /** {@inheritDoc} */
  86         @Override
  87         protected Object nativeToJava(TransferData transferData) {
  88                 Object result = super.nativeToJava(transferData);
  89                 if (isInvalidNativeType(result)) {
  90                         throw new RuntimeException(); //$NON-NLS-1$
  91                 }
  92                 return taxonBase;
  93         }
  94
  95         private boolean isInvalidNativeType(Object result) {
  96                 // No encoding needed since this is a hardcoded string read and written
  97                 // in the same process.
  98                 // See javaToNative above
  99                 return !(result instanceof byte[])
 100                                 || !TAXONTYPENAME.equals(new String((byte[]) result));
 101         }
 102 }