public class SearchEngines extends HttpServlet { public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { String searchString = request.getParameter("searchString"); if ((searchString == null) // (searchString.length() == 0)) { reportPRoblem(response, "Missing search string."); return; } // The URLEncoder changes spaces to "+" signs and other // non-alphanumeric characters to "%XY", where XY is the // hex value of the ASCII (or ISO Latin-1) character. // Browsers always URL-encode form values, so the // getParameter method decodes automatically. But since // we're just passing this on to another server, we need to // re-encode it. searchString = URLEncoder.encode(searchString); String numResults = request.getParameter("numResults"); if ((numResults == null) // (numResults.equals("0")) // (numResults.length() == 0)) { numResults = "10"; } String searchEngine = request.getParameter("searchEngine"); if (searchEngine == null) { reportProblem(response, "Missing search engine name."); return; } SearchSpec[] commonSpecs = SearchSpec.getCommonSpecs(); for(int i=0; i<commonSpecs.length; i++) { SearchSpec searchSpec = commonSpecs; if (searchSpec.getName().equals(searchEngine)) { String url = searchSpec.makeURL(searchString, numResults); response.sendRedirect(url); return; } } reportProblem(response, "Unrecognized search engine."); }
