eu.etaxonomy.taxeditor.editor/src/main/java/eu/etaxonomy/taxeditor/editor/CdmDataTransfer.java

   1 /**
   2 * Copyright (C) 2007 EDIT
   3 * European Distributed Institute of Taxonomy
   4 * http://www.e-taxonomy.eu
   5 *
   6 * The contents of this file are subject to the Mozilla Public License Version 1.1
   7 * See LICENSE.TXT at the top of this package for the full license terms.
   8 */
   9
  10 package eu.etaxonomy.taxeditor.editor;
  11
  12 import java.io.ByteArrayInputStream;
  13 import java.io.ByteArrayOutputStream;
  14 import java.io.DataInputStream;
  15 import java.io.DataOutputStream;
  16 import java.io.EOFException;
  17 import java.io.IOException;
  18 import java.util.ArrayList;
  19 import java.util.List;
  20 import java.util.UUID;
  21
  22 import org.apache.logging.log4j.LogManager;import org.apache.logging.log4j.Logger;
  23 import org.eclipse.swt.dnd.ByteArrayTransfer;
  24 import org.eclipse.swt.dnd.TransferData;
  25
  26 import eu.etaxonomy.cdm.api.service.ITaxonService;
  27 import eu.etaxonomy.cdm.model.common.ICdmBase;
  28 import eu.etaxonomy.cdm.model.taxon.Synonym;
  29 import eu.etaxonomy.cdm.model.taxon.Taxon;
  30 import eu.etaxonomy.taxeditor.store.CdmStore;
  31
  32 /**
  33  * <p>CdmDataTransfer class.</p>
  34  *
  35  * @author n.hoffmann
  36  * @created Jun 18, 2010
  37  */
  38 public class CdmDataTransfer extends ByteArrayTransfer {
  39
  40         @SuppressWarnings("unused")
  41     private static final Logger logger = LogManager.getLogger(CdmDataTransfer.class);
  42
  43         private static int SEPARATOR = -10;
  44         private static int EOF = -20;
  45         private static final String TYPE_NAME = "cdmdata-transfer-format"; //$NON-NLS-1$
  46         private static final int TYPE_ID = registerType (TYPE_NAME);
  47         private static final CdmDataTransfer instance = new CdmDataTransfer();
  48
  49         /**
  50          * <p>Getter for the field <code>instance</code>.</p>
  51          *
  52          * @return a {@link eu.etaxonomy.taxeditor.editor.CdmDataTransfer} object.
  53          */
  54         public static synchronized CdmDataTransfer getInstance() {
  55                 return instance;
  56         }
  57
  58         private ICdmBase cdmBase;
  59
  60         @Override
  61         protected int[] getTypeIds() {
  62                 return new int[] { TYPE_ID };
  63         }
  64
  65         @Override
  66         protected String[] getTypeNames() {
  67                 return new String[]{ TYPE_NAME };
  68         }
  69
  70         @Override
  71         protected void javaToNative(Object object, TransferData transferData) {
  72                 byte[] bytes = toByteArray((ICdmBase[]) object);
  73                 if (bytes != null) {
  74             super.javaToNative(bytes, transferData);
  75         }
  76         }
  77
  78         @Override
  79         protected Object nativeToJava(TransferData transferData) {
  80                 byte[] bytes = (byte[]) super.nativeToJava(transferData);
  81                 return fromByteArray(bytes);
  82         }
  83
  84
  85         private byte[] toByteArray(ICdmBase[] cdmBaseObjects) {
  86                 /**
  87                  * Transfer data is an array of gadgets. Serialized version is: (int)
  88                  * number of gadgets (Gadget) gadget 1 (Gadget) gadget 2 ... repeat for
  89                  * each subsequent gadget see writeGadget for the (Gadget) format.
  90                  */
  91                 ByteArrayOutputStream byteOut = new ByteArrayOutputStream();
  92                 DataOutputStream out = new DataOutputStream(byteOut);
  93
  94                 byte[] bytes = null;
  95
  96                 try {
  97
  98                         for(ICdmBase cdmBaseObject : cdmBaseObjects){
  99                                 writeCdmBaseObject(cdmBaseObject, out);
 100                         }
 101                         out.close();
 102                         bytes = byteOut.toByteArray();
 103                 } catch (IOException e) {
 104                         // when in doubt send nothing
 105                 }
 106                 return bytes;
 107         }
 108
 109
 110         private ICdmBase[] fromByteArray(byte[] bytes) {
 111                 DataInputStream in = new DataInputStream(new ByteArrayInputStream(bytes));
 112
 113                 try {
 114                         List<ICdmBase> cdmBaseObjects = new ArrayList<ICdmBase>();
 115
 116                         try{
 117                                 while(true){
 118                                         cdmBaseObjects.add(readCdmBaseObject(in));
 119                                 }
 120                         }catch(EOFException e){
 121                                 return cdmBaseObjects.toArray(new ICdmBase[]{});
 122                         }
 123                 } catch (IOException e) {
 124                         return null;
 125                 }
 126         }
 127
 128         private ICdmBase readCdmBaseObject(DataInputStream in) throws IOException{
 129                 String className = in.readUTF();
 130                 in.readInt();
 131                 String idString = in.readUTF();
 132                 in.readInt();
 133
 134                 if(className.equals(Synonym.class.getName()) || className.equals(Taxon.class.getName())){
 135                         ICdmBase object = CdmStore.getService(ITaxonService.class).load(UUID.fromString(idString));
 136
 137                         if(object == null){
 138                                 return cdmBase;
 139                         }
 140
 141                         return object;
 142                 }
 143
 144                 return null;
 145         }
 146
 147         private void writeCdmBaseObject(ICdmBase cdmBase, DataOutputStream out) throws IOException{
 148                 /**
 149                  * CdmBase object serialization:
 150                  *
 151                  */
 152                 out.writeUTF(cdmBase.getClass().getName());
 153                 out.writeInt(SEPARATOR);
 154                 out.writeUTF(cdmBase.getUuid().toString());
 155                 out.writeInt(EOF);
 156
 157                 if(cdmBase.getId() == 0){
 158                         // fallback for unsaved instances
 159                         this.cdmBase = cdmBase;
 160                 }
 161         }
 162
 163 }