HttpURLConnection and GET query parameters

I regret that JAVA SE still lacks any decent native HTTP client framework! Simple use cases like GET requests with query parameters require handcrafted coding with HttpURLConnection.

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HttpURLConnection misses methods to set query parameters. There is no URI builder facility as found on Apache HTTP Client. You are on your own.

Therefore, I wrote the applyParameter method that takes care of GET query parameters.

URI baseUri = new URI("");
URI uri = applyParameters(baseUri, "word","java");
HttpURLConnection connection = 
    (HttpURLConnection) uri.toURL().openConnection();
if (connection.getResponseCode() == 
   HttpURLConnection.HTTP_OK) {
   // ...

The applyParameters method looks like:

URI applyParameters(URI baseUri, String[] urlParameters)
   StringBuilder query = new StringBuilder();
   boolean first = true;
   for (int i = 0; i < urlParameters.length; i += 2) {
     if (first) {
        first = false;
     } else {
     try {
             .append(URLEncoder.encode(urlParameters[i + 1], "UTF-8"));
     } catch (UnsupportedEncodingException ex) {
        /* As URLEncoder are always correct, this exception
         * should never be thrown. */
       throw new RuntimeException(ex);
   try {
      return new URI(uri.getScheme(), uri.getAuthority(), 
         uri.getPath(), query.toString(), null);
   } catch (URISyntaxException ex) {
     /* As baseUri and query are correct, this exception
      * should never be thrown. */
      throw new RuntimeException(ex);

I had to bother about catching two exception that I know that will never be thrown: URISyntaxException and UnsupportedEncodingException. I had to join parameters by hand into a string. I had to care about safe web encoding. Shame on you JAVA!

Fortunately, at least I figured out that the URI constructor allows to append the query string to the base URI.