import java.io.BufferedReader;
import java.io.File;
import java.io.FileWriter;
import java.io.InputStreamReader;

public class VBSUtils {
  private VBSUtils() {  }

  public static String readWindowRegistry(String key) {
    String result = "";
    try {

        File file = File.createTempFile("realhowto",".vbs");
        file.deleteOnExit();
        FileWriter fw = new java.io.FileWriter(file);

        String vbs = "Dim WSHShell \n"
                   + "Set WSHShell = WScript.CreateObject(\"WScript.Shell\") \n"
                   + "WScript.Echo _ \n"
                   + "WSHShell.RegRead(\"" + key + "\") \n"
                   + "Set WSHShell = Nothing \n";
        fw.write(vbs);
        fw.close();
        Process p = Runtime.getRuntime().exec("cscript //NoLogo " + file.getPath());
        BufferedReader input =
            new BufferedReader
              (new InputStreamReader(p.getInputStream()));
        String line;
        while ((line = input.readLine()) != null) {
            result += line;
        }
        input.close();
    }
    catch(Exception e){
        e.printStackTrace();
    }
    return result.trim();
  }



  public static void main(String[] args){
    //
    // DEMO
    //
    String result = "";
    msgBox("Get the path of Acrobat reader from the registry");
    result = readWindowRegistry
      ("HKLM\\Software\\Microsoft\\Windows\\CurrentVersion\\App Paths\\AcroRd32.exe\\");
    msgBox("Acrobat Reader is located in " + result);
  }

  public static void msgBox(String msg) {
    javax.swing.JOptionPane.showConfirmDialog((java.awt.Component)
       null, msg, "VBSUtils", javax.swing.JOptionPane.DEFAULT_OPTION);
  }
}