I want to be notified if a string is copied to the system clipboard. When a new string is copied from the same source application, the FlavorListener won't get an event. To get informed when another string is copied, i read the string from the clipboard, convert it to a SrtingSelection, which is able to take the ownership, and put it back to the clipboard. Now I got informed twice, once the StringSelection lost ownership and once it takes it back. Is there a way to check for the ownership directly, instead of storing the string and check it equals the new one?
Here is my code so far:
import java.awt.Toolkit;
import java.awt.datatransfer.Clipboard;
import java.awt.datatransfer.DataFlavor;
import java.awt.datatransfer.FlavorEvent;
import java.awt.datatransfer.FlavorListener;
import java.awt.datatransfer.StringSelection;
import java.awt.datatransfer.Transferable;
import java.awt.datatransfer.UnsupportedFlavorException;
import java.io.IOException;
public class Main {
public static void main(String[] args) throws Exception {
// The clipboard
final Clipboard cb = Toolkit.getDefaultToolkit().getSystemClipboard();
// read clipboard and take ownership to get the FlavorListener notified
// when the content has changed but the owner has not
processClipboard(cb);
cb.addFlavorListener(new FlavorListener() {
@Override
public void flavorsChanged(FlavorEvent e) {
processClipboard(cb);
}
});
// keep thread for testing
Thread.sleep(100000L);
}
public static void processClipboard(Clipboard cb) {
// gets the content of clipboard
Transferable trans = cb.getContents(null);
if (trans.isDataFlavorSupported(DataFlavor.stringFlavor)) {
try {
// cast to string
String s = (String) trans
.getTransferData(DataFlavor.stringFlavor);
System.out.println(s);
// only StringSelection can take ownership, i think
StringSelection ss = new StringSelection(s);
// set content, take ownership
cb.setContents(ss, ss);
} catch (UnsupportedFlavorException e2) {
e2.printStackTrace();
} catch (IOException e2) {
e2.printStackTrace();
}
}
}
}
I hope you understand my bad english :-(
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