This snippet adds a set of parameters to a URL.
URLEncoder.encode() replaces special characters with a %xx sequence, to get a valid URL.
The values of m_day, m_month, m_year are numeric. Since numbers are not special characters, this has no effect.
Also, the fixed string ORDERLEVEL is encoded. (No effect either.)
Then there are 2 fields containing a username and password (which might contain %, # and other things not allowed in a URL) are not encoded.
StringBuffer l_stringBuffer = new StringBuffer(p_data.getUrl());
l_stringBuffer.append("PSPID=" + p_data.getUsr() + "&");
l_stringBuffer.append("PSWD=" + p_data.getPwd()+ "&");
l_stringBuffer.append("level=" + URLEncoder.encode("ORDERLEVEL","UTF-8") + "&");
l_stringBuffer.append("ofd=" + URLEncoder.encode(m_day,"UTF-8") + "&");
l_stringBuffer.append("ofm=" + URLEncoder.encode(m_month,"UTF-8") + "&");
l_stringBuffer.append("ofy=" + URLEncoder.encode(m_year,"UTF-8") + "&");
l_stringBuffer.append("otd=" + URLEncoder.encode(m_day,"UTF-8") + "&");
l_stringBuffer.append("otm=" + URLEncoder.encode(m_month,"UTF-8") + "&");
l_stringBuffer.append("oty=" + URLEncoder.encode(m_year,"UTF-8") + "&");
l_stringBuffer.append("structure=" + "EXT" + "&");
l_stringBuffer.append("format=" + "xml" + "&");
l_stringBuffer.append("st4=" + "1" + "&");
l_stringBuffer.append("st6=" + "1");