Java tutorial
import java.io.FileOutputStream; import java.util.Collections; import java.util.Enumeration; import java.util.Properties; import java.util.Vector; public class Main { public static void main(String[] args) throws Exception { SortedProperties sp = new SortedProperties(); sp.put("B", "value B"); sp.put("C", "value C"); sp.put("A", "value A"); sp.put("D", "value D"); FileOutputStream fos = new FileOutputStream("sp.props"); sp.store(fos, "sorted props"); } } class SortedProperties extends Properties { public Enumeration keys() { Enumeration keysEnum = super.keys(); Vector<String> keyList = new Vector<String>(); while (keysEnum.hasMoreElements()) { keyList.add((String) keysEnum.nextElement()); } Collections.sort(keyList); return keyList.elements(); } }