Problem with return statement

ArrayList<String> ListNameMagazine = new ArrayList<String>();

ShowData Show = new ShowData();

    int HowManyMagazine = Show.HowManyMagazine(1); // to make sure there is how many Magazine name in my database

    //System.out.print(HowManyMagazine); //i want to make sure the data is out.

    String nmeMagazine = null; // this variable for get data from return statement

    // i want to store in ListNameMagazine
    ArrayList<String> ListNameMagazine = new ArrayList<String>();

    for (int numbeer = 0;numbeer <= HowManyMagazine ; numbeer++)
    {
       //Store in 1 variable String, because if arrayList it's error
        nmeMagazine = Show.getResult("Select Name_Magazine from Magazine");
        // Store again in array list
        ListNameMagazine.add(nmeMagazine);
    }

    for (String s : ListNameMagazine)
    {
        System.out.println(s); // show the data
    }

public String getResult(String sql)
throws SQLException
{
    ResultSet rs = st.executeQuery(sql);
    ResultSetMetaData resultsetmetadata = rs.getMetaData();

    //String just_try = null;
    while (rs.next()) {
         System.out.println("Result:"+rs.getString(1));
         //just_try = rs.getString(1);
         //return just_try;
    }
    return null;    //return just_try;
}

public String getResult(String sql)
throws SQLException
{
     ResultSet rs = st.executeQuery(sql);
     ResultSetMetaData resultsetmetadata = rs.getMetaData();
     String just_try = null;

     while (rs.next()) {
         //System.out.println("Result:"+rs.getString(1));
        just_try = rs.getString(1);
        return just_try;
     }

     return just_try;
 }

for (String s : ListNameMagazine)
    {
        System.out.println(s); // show the data
    }

public String getResult(String sql)
throws SQLException
    {
    ResultSet rs = st.executeQuery(sql);
    ResultSetMetaData resultsetmetadata = rs.getMetaData();
    String just_try = null;

    while (rs.next()) {
        System.out.println("Result:"+rs.getString(1));
        //just_try = rs.getString(1);
        //return just_try;
    }

    return null;
}

while (rs.next()) {

    //System.out.println("Result:"+rs.getString(1));

   just_try = rs.getString(1);

  return just_try;

}

just_try = rs.getString(1);

return just_try;

ArrayList<String> ListNameMagazine;
ListNameMagazine = Show.getResult("Select Name_Magazine from Magazine");

public ArrayList<String> getResult(String sql) throws SQLException {

    ResultSet rs = st.executeQuery(sql);

    ResultSetMetaData resultsetmetadata = rs.getMetaData();

    ArrayList<String> returnArrayList = new ArrayList<String>();

    while (rs.next()) {

        returnArrayList.add(rs.getString(1));

    }
    return returnArrayList;

}

public List<String> getResult(String sql) throws SQLException;