class FileDropHandler extends TransferHandler {

private static final long serialVersionUID = 1L;

def wordsToFind =[]
JTextArea output
private JLabel errorMsg;
private String fileText = "";
private boolean test = false;
private boolean same = true;

public boolean canImport(TransferSupport supp) {
/* for the demo, we'll only support drops (not clipboard paste) */
if (!supp.isDrop()) {
return false;
}

/* return false if the drop doesn't contain a list of files */
if (!supp.isDataFlavorSupported(DataFlavor.javaFileListFlavor)) {
return false;
}

boolean copySupported = (COPY & supp.getSourceDropActions()) == COPY;

if (copySupported) {
supp.setDropAction(COPY);
return true;
}

return false;
}

public boolean importData(TransferSupport supp) {
if (!canImport(supp)) {
return false;
}

/* get the Transferable */
Transferable t = supp.getTransferable();

try {

Object data = t.getTransferData(DataFlavor.javaFileListFlavor);

List fileList = (List) data;

for (int j = 0; j < fileList.size(); j++) {

File file = (File) fileList.get(j);
//file.getAbsolutePath()
def tmpfh = new File("FileParser.txt")
println wordsToFind.inspect()
new File(file.getAbsolutePath()).eachLine{line->
wordsToFind.each{ if(line =~ "${it}" ){
println "${line}"
tmpfh.append(line)
tmpfh.append("\n\n")
this.output.setText(this.output.getText()+line+"\n")
}
}
}//end for

tmpfh.close()

}
} catch (UnsupportedFlavorException e) {
return false;
} catch (IOException e) {
return false;
} catch (NoSuchAlgorithmException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}

return true;
}

public void setOutput(JTextArea jta) {
this.output = jta;
}

public void setOutput(JLabel jta) {
errorMsg = jta;
}

public String getText() {
return fileText;
}

public void clearAll() {
fileText = "";
test = false;
same = true;

}
}

class AL implements ActionListener{
public JTextField jtf
public FileDropHandler dh
public AL(JTextField jtf,FileDropHandler dh){
this.jtf = jtf
this.dh =dh
}
public void actionPerformed(ActionEvent actionEvent){
println "${this.jtf.getText()}"
dh.wordsToFind= this.jtf.getText().split(' ')
}
}

JTextArea dTextArea = new JTextArea("Drop on me");
FileDropHandler dh = new FileDropHandler()
dh.setOutput(dTextArea)
JTextField jta = new JTextField("Enter words seperated by spaces")
dh.wordsToFind= jta.getText().split(' ')
JButton jb =new JButton("Update Word List")
jb.addActionListener( new AL(jta ,dh ))

dh.setOutput(dTextArea);
dTextArea.setDragEnabled(true);
dTextArea.setTransferHandler(dh);

JPanel p =new JPanel(new BorderLayout());
JFrame f = new JFrame()
p.add(jta, BorderLayout.NORTH)
p.add(dTextArea, BorderLayout.CENTER)
p.add(jb, BorderLayout.SOUTH)