import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.util.Properties;
public class Main {
public static void main(String[] argv) throws Exception {
// Read properties file.
Properties properties = new Properties();
try {
properties.load(new FileInputStream("filename.properties"));
} catch (IOException e) {
}
// Write properties file.
try {
properties.store(new FileOutputStream("filename.properties"), null);
} catch (IOException e) {
}
}
}