import java.io.Console;
import java.io.IOException;
import java.io.PrintWriter;
+import java.util.Arrays;
import java.util.Locale;
import javax.security.auth.callback.Callback;
writer.write(callback.getPrompt());
char[] answer = console.readPassword();
callback.setPassword(answer);
+ Arrays.fill(answer, ' ');
} else if (callbacks[i] instanceof LocaleCallback) {
LocaleCallback callback = (LocaleCallback) callbacks[i];
writer.write(callback.getPrompt());