1

に D&D を実装していJTreeます。カスタムTransferHandlerを作成し、新しいTransferableクラスを作成しました。このクラスはとても簡単です:

public class TreePathTransferable implements Transferable{

  private static final DataFlavor[] flavors = new DataFlavor[] {
          new DataFlavor(TreePath[].class,"TreePaths")};

  private TreePath[] data;

  public TreePathTransferable(TreePath[] data) {
    super();
    this.data = data;
  }

  public DataFlavor[] getTransferDataFlavors() {
    return flavors;
  }

  public boolean isDataFlavorSupported(DataFlavor flavor) {
    return flavors[0].equals(flavor);
  }

  public TreePath[] getTransferData(DataFlavor flavor) throws
          UnsupportedFlavorException, IOException{
    return data;
  }
}

「オンドロップ」の場合、私は電話します

dtde.getTransferable().getTransferData(dtde.getTransferable().getTransferDataFlavors()[0])

を取得しjava.io.NotSerializableExceptionます。次の方法でデータオブジェクトのクラスを変更するTreePathTransferableObject:

public class TreePathTransferable implements Transferable{

  private static final DataFlavor[] flavors = new DataFlavor[] {
          new DataFlavor(Object.class,"Object")};

  private Object data;

  public TreePathTransferable(Object data) {
    super();
    this.data = data;
  }

  public DataFlavor[] getTransferDataFlavors() {
    return flavors;
  }

  public boolean isDataFlavorSupported(DataFlavor flavor) {
    return flavors[0].equals(flavor);
  }

  public Object getTransferData(DataFlavor flavor) throws
          UnsupportedFlavorException, IOException{
    return data;
  }

}

すべて正常に動作します。転送されたデータは同じなので、これは私には意味がありません - TreePath[]。違いはなぜですか?

スタックトレース

注: シリアル化できないクラスを XXX に置き換えました。これは、DefaultMutableTreeNode のサブクラスのプロパティです。このサブクラスはシリアル化できないため、例外は意味がありますが、なぜ 2 番目のケースに表示されないのでしょうか?

java.io.NotSerializableException: XXX
    at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1184)
    at java.io.ObjectOutputStream.defaultWriteFields(ObjectOutputStream.java:1548)
    at java.io.ObjectOutputStream.writeSerialData(ObjectOutputStream.java:1509)
    at java.io.ObjectOutputStream.writeOrdinaryObject(ObjectOutputStream.java:1432)
    at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1178)
    at java.io.ObjectOutputStream.writeObject(ObjectOutputStream.java:348)
    at java.util.HashMap.internalWriteEntries(HashMap.java:1777)
    at java.util.HashMap.writeObject(HashMap.java:1354)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:497)
    at java.io.ObjectStreamClass.invokeWriteObject(ObjectStreamClass.java:988)
    at java.io.ObjectOutputStream.writeSerialData(ObjectOutputStream.java:1496)
    at java.io.ObjectOutputStream.writeOrdinaryObject(ObjectOutputStream.java:1432)
    at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1178)
    at java.io.ObjectOutputStream.defaultWriteFields(ObjectOutputStream.java:1548)
    at java.io.ObjectOutputStream.writeSerialData(ObjectOutputStream.java:1509)
    at java.io.ObjectOutputStream.writeOrdinaryObject(ObjectOutputStream.java:1432)
    at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1178)
    at java.io.ObjectOutputStream.writeArray(ObjectOutputStream.java:1378)
    at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1174)
    at java.io.ObjectOutputStream.writeObject(ObjectOutputStream.java:348)
    at javax.swing.tree.DefaultMutableTreeNode.writeObject(DefaultMutableTreeNode.java:1287)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:497)
    at java.io.ObjectStreamClass.invokeWriteObject(ObjectStreamClass.java:988)
    at java.io.ObjectOutputStream.writeSerialData(ObjectOutputStream.java:1496)
    at java.io.ObjectOutputStream.writeOrdinaryObject(ObjectOutputStream.java:1432)
    at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1178)
    at java.io.ObjectOutputStream.writeArray(ObjectOutputStream.java:1378)
    at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1174)
    at java.io.ObjectOutputStream.access$300(ObjectOutputStream.java:162)
    at java.io.ObjectOutputStream$PutFieldImpl.writeFields(ObjectOutputStream.java:1707)
    at java.io.ObjectOutputStream.writeFields(ObjectOutputStream.java:482)
    at java.util.Vector.writeObject(Vector.java:1077)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:497)
    at java.io.ObjectStreamClass.invokeWriteObject(ObjectStreamClass.java:988)
    at java.io.ObjectOutputStream.writeSerialData(ObjectOutputStream.java:1496)
    at java.io.ObjectOutputStream.writeOrdinaryObject(ObjectOutputStream.java:1432)
    at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1178)
    at java.io.ObjectOutputStream.defaultWriteFields(ObjectOutputStream.java:1548)
    at java.io.ObjectOutputStream.defaultWriteObject(ObjectOutputStream.java:441)
    at javax.swing.tree.DefaultMutableTreeNode.writeObject(DefaultMutableTreeNode.java:1278)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:497)
    at java.io.ObjectStreamClass.invokeWriteObject(ObjectStreamClass.java:988)
    at java.io.ObjectOutputStream.writeSerialData(ObjectOutputStream.java:1496)
    at java.io.ObjectOutputStream.writeOrdinaryObject(ObjectOutputStream.java:1432)
    at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1178)
    at java.io.ObjectOutputStream.defaultWriteFields(ObjectOutputStream.java:1548)
    at java.io.ObjectOutputStream.defaultWriteObject(ObjectOutputStream.java:441)
    at javax.swing.tree.DefaultMutableTreeNode.writeObject(DefaultMutableTreeNode.java:1278)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:497)
    at java.io.ObjectStreamClass.invokeWriteObject(ObjectStreamClass.java:988)
    at java.io.ObjectOutputStream.writeSerialData(ObjectOutputStream.java:1496)
    at java.io.ObjectOutputStream.writeOrdinaryObject(ObjectOutputStream.java:1432)
    at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1178)
    at java.io.ObjectOutputStream.defaultWriteFields(ObjectOutputStream.java:1548)
    at java.io.ObjectOutputStream.defaultWriteObject(ObjectOutputStream.java:441)
    at javax.swing.tree.DefaultMutableTreeNode.writeObject(DefaultMutableTreeNode.java:1278)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:497)
    at java.io.ObjectStreamClass.invokeWriteObject(ObjectStreamClass.java:988)
    at java.io.ObjectOutputStream.writeSerialData(ObjectOutputStream.java:1496)
    at java.io.ObjectOutputStream.writeOrdinaryObject(ObjectOutputStream.java:1432)
    at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1178)
    at java.io.ObjectOutputStream.defaultWriteFields(ObjectOutputStream.java:1548)
    at java.io.ObjectOutputStream.defaultWriteObject(ObjectOutputStream.java:441)
    at javax.swing.tree.DefaultMutableTreeNode.writeObject(DefaultMutableTreeNode.java:1278)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:497)
    at java.io.ObjectStreamClass.invokeWriteObject(ObjectStreamClass.java:988)
    at java.io.ObjectOutputStream.writeSerialData(ObjectOutputStream.java:1496)
    at java.io.ObjectOutputStream.writeOrdinaryObject(ObjectOutputStream.java:1432)
    at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1178)
    at java.io.ObjectOutputStream.defaultWriteFields(ObjectOutputStream.java:1548)
    at java.io.ObjectOutputStream.writeSerialData(ObjectOutputStream.java:1509)
    at java.io.ObjectOutputStream.writeOrdinaryObject(ObjectOutputStream.java:1432)
    at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1178)
    at java.io.ObjectOutputStream.writeArray(ObjectOutputStream.java:1378)
    at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1174)
    at java.io.ObjectOutputStream.writeObject(ObjectOutputStream.java:348)
    at sun.awt.datatransfer.TransferableProxy.getTransferData(TransferableProxy.java:83)
    at java.awt.dnd.DropTargetContext$TransferableProxy.getTransferData(DropTargetContext.java:376)

TransferHandler

public class MyTreeTransferHandler extends TransferHandler {
  public MyTreeTransferHandler() {
    super();
  }

  protected Transferable createTransferable(JComponent c) {
    Transferable t = null;
    if(c instanceof JTree) {
      JTree tree = (JTree) c;
        t = new TreePathTransferable(tree.getSelectionPaths());
        return t;
    }
    return t;
  }

  public int getSourceActions(JComponent c) {
    return TransferHandler.MOVE;
  }

  public boolean canImport(JComponent c, DataFlavor[] flavors){
    return true;
  }
}
4

1 に答える 1