Java - Properties: Add new keys to properties file in run time?

Is it possible to create a new properties file and add keys and values in run time? I want to add new keys to properties file depending on user input w开发者_StackOverflowhile installing my application. I checked out Java Properties class but it seem it can set values to existing keys but can not add new keys to properties file.

You can add new properties just by calling setProperty with a key which doesn't currently exist. That will only do it in memory though - you'll have to call store again to reflect the changes back to a file:

Properties prop = new Properties();
prop.load(...); // FileInputStream or whatever

prop.setProperty("newKey", "newValue");
prop.store(...); // FileOutputStream or whatever