Java code to read the windows registry

The following code will show us the proxy settings of the internet explorer and the version of the same.
Useful APIs

Preferences
Method

import java.lang.reflect.Method;
import java.util.prefs.Preferences;


public class JavaRegistryReader {
private static final int HKEY_CURRENT_USER = 0x80000001;
private static final int KEY_QUERY_VALUE = 1;
private static final int KEY_SET_VALUE = 2;
private static final int KEY_READ = 0x20019;
public static void main(String args[]) {
final Preferences userRoot = Preferences.userRoot();
final Preferences systemRoot = Preferences.systemRoot();
final Class clz = userRoot.getClass();
try {
final Method openKey = clz.getDeclaredMethod("openKey",byte[].class, int.class, int.class);
openKey.setAccessible(true);
final Method closeKey = clz.getDeclaredMethod("closeKey",int.class);
closeKey.setAccessible(true);
final Method winRegQueryValue = clz.getDeclaredMethod("WindowsRegQueryValueEx", int.class, byte[].class);
winRegQueryValue.setAccessible(true);
final Method winRegEnumValue = clz.getDeclaredMethod("WindowsRegEnumValue1", int.class, int.class, int.class);
winRegEnumValue.setAccessible(true);
final Method winRegQueryInfo = clz.getDeclaredMethod("WindowsRegQueryInfoKey1", int.class);
winRegQueryInfo.setAccessible(true);
byte[] valb = null;
String vals = null;
String key = null;
Integer handle = -1;
//Query Internet Settings for Proxy
key = "Software\\Microsoft\\Windows\\CurrentVersion\\Internet Settings";
handle = (Integer) openKey.invoke(userRoot, toCstr(key), KEY_READ, KEY_READ);
valb = (byte[]) winRegQueryValue.invoke(userRoot, handle.intValue(),toCstr("ProxyServer"));
vals = (valb != null ? new String(valb).trim() : null);
System.out.println("Proxy Server = " + vals);
closeKey.invoke(Preferences.userRoot(), handle);
// Query for IE version
key = "SOFTWARE\\Microsoft\\Internet Explorer";
handle = (Integer) openKey.invoke(systemRoot, toCstr(key), KEY_READ, KEY_READ);
valb = (byte[]) winRegQueryValue.invoke(systemRoot, handle, toCstr("Version"));
vals = (valb != null ? new String(valb).trim() : null);
System.out.println("Internet Explorer Version = " + vals);
closeKey.invoke(Preferences.systemRoot(), handle);
} catch (Exception e) {
e.printStackTrace();
}
}
private static byte[] toCstr(String str) {
byte[] result = new byte[str.length() + 1];
for (int i = 0; i < str.length(); i++) {
result[i] = (byte) str.charAt(i);
}
result[str.length()] = 0;
return result;
}
}

Thanks