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Retrieving All Parameters To A Java Servlet

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// Ref:
// The getParameterMap() returns a Map that has Strings as keys and String[] as
// values. That's so you can have ?x=1&x=2&x=3 in your URL query string. The
// keys in the Map must be unique but there can be multiple values for each
// key.
// So.. when you pull a value out of a Map created by the getParameterMap()
// method you must cast it to a String[] or else you'll get the value's
// location in memory instead of it's actual value. If you're writing the
// code and know for a fact that you'll always have only one value for each
// param then you can just use yourVar[0] but if there may be multiple
// values for each key then you'll need to loop over each value array.

    Map params = request.getParameterMap();
    Iterator i = params.keySet().iterator();
    while ( i.hasNext() )
        String key = (String);
        String value = ((String[]) params.get( key ))[ 0 ];