try {
name = new String("是否".getBytes("iso8859-1"),"GBK");
password = new String("11111".getBytes("iso8859-1"),"GBK");
message = new String("发送短信测试".getBytes("iso8859-1"),"GBK");
} catch (UnsupportedEncodingException e1) {
e1.printStackTrace();
}
//这里就是你说的插件返回的值？  
Sender sms = new Sender(name,password);
String returnCode = sms.massSend("13633618954",message ,
new String("时间".getBytes("iso8859-1"),"GBK"),
new String("特服代码".getBytes("iso8859-1"),"GBK"));

String encode = null;
try{
//这里是多余的吧?
encode = new String(returnCode.getBytes("iso8859-1"),"GBK");
}catch(Exception e){
e.printStackTrace();
}
System.out.println(encode);