如何在Java中清除系统剪贴板？

Question

如何清除Java中的System Clipboard？我试过了

Toolkit.getDefaultToolkit().getSystemClipboard().setContents(null, null);

但它刚刚抛出NPE：

Exception in thread "AWT-EventQueue-0" java.lang.NullPointerException: contents
    at sun.awt.datatransfer.SunClipboard.setContents(SunClipboard.java:98)

Answer 1

您可以创建一个明确不包含任何数据的特殊Transferable，详细信息为in this blog post：

  clipboard.setContents(new Transferable() {
    public DataFlavor[] getTransferDataFlavors() {
      return new DataFlavor[0];
    }

    public boolean isDataFlavorSupported(DataFlavor flavor) {
      return false;
    }

    public Object getTransferData(DataFlavor flavor) throws UnsupportedFlavorException {
      throw new UnsupportedFlavorException(flavor);
    }

Answer 2

你可以这样做：

StringSelection stringSelection = new StringSelection("");
Toolkit.getDefaultToolkit().getSystemClipboard().setContents(
            stringSelection, null);

自StringSelection implements Transferable

以来

public class StringSelection implements Transferable, ClipboardOwner