I want to filter

[AC Question]

ResultSet rs;
try {
Statement statement = conn.createStatement();
rs = statement.executeQuery(COMANDOSQL);
data = new ArrayList<Map<String,String>>();
while(rs.next()){
Map<String, String> datanum = new HashMap<String, String>();
datanum.put("A", rs.getString("code"));
datanum.put("B", rs.getString("description"));
datanum.put("C", rs.getString("BALQTY"));
data.add(datanum);
}
String[] from = {"A","B","C"};
int[] views = {R.id.text_code,R.id.text_desc , R.id.text_qty};
AD = new SimpleAdapter(this, data, R.layout.listitems, from, views);
lv.setAdapter(AD);
} catch (Exception e) {
Log.e("ERRO",e.getMessage());
}
I tried to filter with below code but it's showing me duplicate value while I type some text.

et.addTextChangedListener(new TextWatcher() {
public void onTextChanged(CharSequence s, int start, int before, int count) {
AD.getFilter().filter(s.toString());
}
public void beforeTextChanged(CharSequence s, int start, int count, int after) {
System.out.println("before changed");
}
public void afterTextChanged(Editable s) {
}
});