How to receive the return of selected text inside in windows?

No, there are no classes for this functionality within the Java SE Platform or Java EE Platform. Which does not mean you can not build this functionality using Java, it's perfectly possible. You will need to write native code. This will actually lock your code more to the Operating System in your Windows case.

For this Java proves what we call JNI

Java Native Interface

Check out documentation here: link

read this other tutorial carefully

link

Last, but not least, I found this code made for someone wanted to do something similar myth to what you want to do:

import java.awt.Toolkit;
import java.awt.datatransfer.Clipboard;
import java.awt.datatransfer.ClipboardOwner;
import java.awt.datatransfer.DataFlavor;
import java.awt.datatransfer.StringSelection;
import java.awt.datatransfer.Transferable;

import com.sun.jna.Native;
import com.sun.jna.platform.win32.User32;
import com.sun.jna.platform.win32.WinDef.HWND;
import com.sun.jna.win32.StdCallLibrary;

public class Foo implements ClipboardOwner {
    public interface CustomUser32 extends StdCallLibrary {
        CustomUser32 INSTANCE = (CustomUser32) Native.loadLibrary("user32", CustomUser32.class);
        HWND GetForegroundWindow();
        void keybd_event(byte bVk, byte bScan, int dwFlags, int dwExtraInfo);
    }

    public void lostOwnership(Clipboard clipboard, Transferable contents) {
        // dummy: needed for 'ClipboardOwner'
    }

    void controlC(CustomUser32 customUser32) {
        customUser32.keybd_event((byte) 0x11 /* VK_CONTROL*/, (byte) 0, 0, 0);
        customUser32.keybd_event((byte) 0x43 /* 'C' */, (byte) 0, 0, 0);
        customUser32.keybd_event((byte) 0x43 /* 'C' */, (byte) 0, 2 /* KEYEVENTF_KEYUP */, 0);
        customUser32.keybd_event((byte) 0x11 /* VK_CONTROL*/, (byte) 0, 2 /* KEYEVENTF_KEYUP */, 0);// 'Left Control Up
    }

    String getClipboardText() throws Exception {
        return (String) Toolkit.getDefaultToolkit().getSystemClipboard().getData(DataFlavor.stringFlavor);
    }

    void setClipboardText(String data) throws Exception {
        Toolkit.getDefaultToolkit().getSystemClipboard().setContents(new StringSelection(data), this);
    }

    String getSelectedText(User32 user32, CustomUser32 customUser32) throws Exception {
        HWND hwnd = customUser32.GetForegroundWindow();
        char[] windowText = new char[512];
        user32.GetWindowText(hwnd, windowText, 512);
        String windowTitle = Native.toString(windowText);
        System.out.println("Will take selected text from the following window: [" + windowTitle + "]");
        String before = getClipboardText();
        controlC(customUser32); // emulate Ctrl C
        Thread.sleep(100); // give it some time
        String text = getClipboardText();
        System.out.println("Currently in clipboard: " + text);
        // restore what was previously in the clipboard
        setClipboardText(before);
        return text;
    }

    public static void main(String[] args) throws Exception {
        Foo foo = new Foo();
        Thread.sleep(2000); // take some time for you to select something anywhere
        System.out.println(foo.getSelectedText(User32.INSTANCE, CustomUser32.INSTANCE));
    }
}

When you run, you will have two seconds to select text in any application, and then you will start typing these strings.

Source: link