Sending Json via android GET

Problem in special characters ( keys, parentheses, etc. ) that contains a json that I'm sending via GET . The android generates the following log:

> E/AndroidRuntime(1956): java.lang.IllegalArgumentException: Illegal
> character in path at index 61:
> http://10.0.3.2:8084/meuapp/recurso/objeto/download/{}

My GET method is as follows

public static String GET(Context context, String endereco){
        //Verifica se existe conexão com a internet
        if(!existeConexao(context))
            return K.FALHA_CONEXAO;
        InputStream inputStream = null;
        HttpClient httpClient = new DefaultHttpClient();
        String result = K.FALHA;
        try{
            HttpGet httpGet = new HttpGet(endereco);//A excessão acontece aqui
            HttpResponse httpResponse = httpClient.execute(httpGet);
            inputStream = httpResponse.getEntity().getContent();
            if(inputStream!=null){
                //Converte resposta do WebService para String
                result = inputStreamParaString(inputStream);
            }else
                result = K.FALHA;
        }catch(UnsupportedEncodingException e){
            e.printStackTrace();
        }catch(ClientProtocolException e){
            e.printStackTrace();
        }catch(IOException e){
            e.printStackTrace();
        }


        return result;
    }