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