get/pass parameters from the http query string. I use the history token to pass paramters, which makes more sense, since you don’t have to refresh the page. Here is my method I do it with.

/**
* init history support, start watching for changes in history
*
* observe history changes (tokens)
*/
public void initHistorySupport() {

History.addHistoryListener(this);

// check to see if there are any tokens passed at startup via the
// browser’s URI
String token = History.getToken();
if (token.length() == 0) {
onHistoryChanged(”trainer”);
} else {
onHistoryChanged(token);
}
}

/**
* parse history token ?[var=1&var2=2&var3=3]
*
* Parse the history token like querystring - domain.tld#historyToken?params
*
* @param historyToken
* @return
*/
public static HashMap parseHistoryToken(String historyToken) {

//skip if there is no question mark
if (!historyToken.contains(”?”)) {
return null;
}

// ? position
int questionMarkIndex = historyToken.indexOf(”?”) + 1;

//get the sub string of parameters var=1&var2=2&var3=3…
String[] arStr = historyToken.substring(questionMarkIndex, historyToken.length()).split(”&”);

HashMap params = new HashMap();
for (int i = 0; i < arStr.length; i++) {

String[] substr = arStr[i].split("=");

params.put(substr[0], substr[1]);

//debug
System.out.println("param[" + i + "]=" + arStr[i]);
}

//debug
System.out.println("map: " + params);

return params;

}