This Java tip illustrates a method of reading and writing a Properties file. Developer may read by using input stream and write by using output stream.

Here is an example of the contents of a properties file:

 # a comment
    ! a comment
    
    a = a string
    b = a string with escape sequences \t \n \r \\ \" \' \ (space) \u0123
    c = a string with a continuation line \
        continuation line
    d.e.f = another string
  // Read properties file.
    Properties prop = new Properties();

    try {
        prop.load(new FileInputStream("filename.properties"));
    } catch (IOException e) {
    }
    
    // Write properties file.
    try {
        prop.store(new FileOutputStream("filename.properties"), null);
    } catch (IOException e) {
    }