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/**
* @version 1.00 1999-09-11
* @author Cay Horstmann
*/
import java.awt.Container;
import java.awt.datatransfer.DataFlavor;
import java.awt.datatransfer.Transferable;
import java.awt.dnd.DnDConstants;
import java.awt.dnd.DropTarget;
import java.awt.dnd.DropTargetDragEvent;
import java.awt.dnd.DropTargetDropEvent;
import java.awt.dnd.DropTargetEvent;
import java.awt.dnd.DropTargetListener;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;
import java.io.File;
import java.io.InputStream;
import java.util.Iterator;
import javax.swing.JFrame;
import javax.swing.JScrollPane;
import javax.swing.JTextArea;
public class DropTargetTest {
public static void main(String[] args) {
JFrame frame = new DropTargetFrame();
frame.show();
}
}
class DropTargetFrame extends JFrame {
public DropTargetFrame() {
setTitle("DropTarget");
setSize(300, 300);
addWindowListener(new WindowAdapter() {
public void windowClosing(WindowEvent e) {
System.exit(0);
}
});
Container contentPane = getContentPane();
JTextArea textArea = new JTextArea("Drop items into this text area.\n");
new DropTarget(textArea, new TextDropTargetListener(textArea));
contentPane.add(new JScrollPane(textArea), "Center");
}
}
class TextDropTargetListener implements DropTargetListener {
public TextDropTargetListener(JTextArea ta) {
textArea = ta;
}
public void dragEnter(DropTargetDragEvent event) {
int a = event.getDropAction();
if ((a & DnDConstants.ACTION_COPY) != 0)
textArea.append("ACTION_COPY\n");
if ((a & DnDConstants.ACTION_MOVE) != 0)
textArea.append("ACTION_MOVE\n");
if ((a & DnDConstants.ACTION_LINK) != 0)
textArea.append("ACTION_LINK\n");
if (!isDragAcceptable(event)) {
event.rejectDrag();
return;
}
}
public void dragExit(DropTargetEvent event) {
}
public void dragOver(DropTargetDragEvent event) { // you can provide visual
// feedback here
}
public void dropActionChanged(DropTargetDragEvent event) {
if (!isDragAcceptable(event)) {
event.rejectDrag();
return;
}
}
public void drop(DropTargetDropEvent event) {
if (!isDropAcceptable(event)) {
event.rejectDrop();
return;
}
event.acceptDrop(DnDConstants.ACTION_COPY);
Transferable transferable = event.getTransferable();
DataFlavor[] flavors = transferable.getTransferDataFlavors();
for (int i = 0; i < flavors.length; i++) {
DataFlavor d = flavors[i];
textArea.append("MIME type=" + d.getMimeType() + "\n");
try {
if (d.equals(DataFlavor.javaFileListFlavor)) {
java.util.List fileList = (java.util.List) transferable
.getTransferData(d);
Iterator iterator = fileList.iterator();
while (iterator.hasNext()) {
File f = (File) iterator.next();
textArea.append(f + "\n");
}
} else if (d.equals(DataFlavor.stringFlavor)) {
String s = (String) transferable.getTransferData(d);
textArea.append(s + "\n");
} else if (d.isMimeTypeEqual("text/plain")) {
String charset = d.getParameter("charset");
InputStream in = (InputStream) transferable
.getTransferData(d);
boolean more = true;
int ch;
if (charset.equals("ascii")) {
do {
ch = in.read();
if (ch != 0 && ch != -1)
textArea.append("" + (char) ch);
else
more = false;
} while (more);
} else if (charset.equals("unicode")) {
boolean littleEndian = true;
// if no byte ordering mark, we assume
// Windows is the culprit
do {
ch = in.read();
int ch2 = in.read();
if (ch != -1 && littleEndian)
ch = (ch & 0xFF) | ((ch2 & 0xFF) << 8);
if (ch == 0xFFFE)
littleEndian = false;
else if (ch != 0 && ch != -1)
textArea.append("" + (char) ch);
else
more = false;
} while (more);
}
textArea.append("\n");
}
} catch (Exception e) {
textArea.append("Error: " + e + "\n");
}
}
event.dropComplete(true);
}
public boolean isDragAcceptable(DropTargetDragEvent event) { // usually, you
// check the
// available
// data flavors
// here
// in this program, we accept all flavors
return (event.getDropAction() & DnDConstants.ACTION_COPY_OR_MOVE) != 0;
}
public boolean isDropAcceptable(DropTargetDropEvent event) { // usually, you
// check the
// available
// data flavors
// here
// in this program, we accept all flavors
return (event.getDropAction() & DnDConstants.ACTION_COPY_OR_MOVE) != 0;
}
private JTextArea textArea;
}
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