I know how to write text to a file and store it in Java, but I was wondering if there is a way of storing lots of variables that can be retrieved from the file at a later date, and put back into the Java application as variables.
I would be storing numbers and strings, but groups of them.
Thanks :)
Java can read properties files like it reads a map. This gives you an easy way of storing information using a key/value system.
Check out http://download.oracle.com/javase/6/docs/api/java/util/Properties.html
Use XML! You will make your variables portable. Even your coffee machine will be able to use them.
A SAX parser is built in Java.
Here is a Java snippet for writing an XML file:
public void saveToXML(String xml) {
Document dom;
Element e = null;
// get an instance of factory
DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
try {
// using a factory get an instance of document builder
DocumentBuilder db = dbf.newDocumentBuilder();
// create an instance of DOM
dom = db.newDocument();
// create the root element
Element rootElement = dom.createElement("myparameters");
// create data elements and place them under root
e = dom.createElement("brightness");
e.appendChild(dom.createTextNode(brightness));
rootElement.appendChild(e);
Here is a Java snippet for reading an XML file:
public boolean loadFromXML(String xml) {
Document dom;
// get an instance of the factory
DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
try {
// using factory get an instance of the document builder
DocumentBuilder db = dbf.newDocumentBuilder();
// parse using builder to get DOM representation of the XML file
dom = db.parse(xml);
Element doc = dom.getDocumentElement();
// get the data
brightness = getTextValue(brightness, doc, "brightness");
contrast = getTextValue(contrast, doc, "contrast");
Wel the best way to do this is to make an XML file. It can store any object in any sort of collection.
I guess the XML is the best way to keep it and retrieve it later on.
